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thyroid regulation of body temperature in anaesthetized chickens.1. anaesthesia caused marked decreases in the plasma concentrations of triiodothyronine (t3) and thyroxine (t4) and in the body temperature of young fowl. 2. exogenous t4 or a thyroid hormone secretagogue (somatostatin antiserum), increased endogenous t3 and t4 concentrations and body temperature in conscious birds and prevented the body temperature decline in anaesthetized fowl. 3. these results provide further evidence for a role of t3 and t4 in temperature regulation in birds, particularly du ...19901970531
effect of immunization against somatostatin in the pregnant ewe on growth and endocrine status of the neonatal lamb.absorption of somatostatin (srif) specific antibodies from colostrum of ewes actively immunized against srif may improve growth rate of the neonatal lamb by neutralizing the inhibitory effects of srif on pituitary and thyroid function. growth and endocrine parameters in the offspring of srif immunized (si) and control (c) crossbred ewes were examined. lamb weight was recorded at birth and twice each week to 24 days of age. blood samples were collected prior to first suckle and twice each week. a ...19901973364
species differences in liver type i iodothyronine deiodinase.the type i iodothyronine deiodinase (id-i) of liver is an important enzyme for the conversion of the prohormone thyroxine (t4) to the active thyroid hormone 3,3',5-triiodothyronine (t3). because it is an integral membrane protein of low abundance, purification of id-i from rat liver has proven to be difficult. we have analyzed id-i in liver microsomal fractions from various animals to reveal possible species differences and to explore alternative sources for the isolation of the enzyme. id-i was ...19921599938
role of the thyroid gland in seasonal reproduction. ii. thyroxine allows a season-specific suppression of gonadotropin secretion in sheep.a series of four experiments was conducted to examine the previously described phenomenon that the thyroid gland is required for the breeding season to end in female sheep. exp 1 tested the hypothesis that the thyroid is required because of its secretion of t4. ewes thyroidectomized (thx) in the anestrous season either received t4 replacement or no further treatment; seasonal reproductive shifts were compared to those of thyroid-intact controls. all ewes were housed in conditions in which the en ...19912055181
thyroid function in the newborn lamb. physiological approach of the mechanisms inducing the changes in plasma thyroxine, free thyroxine and triiodothyronine concentrations.several experiments were performed to study the mechanisms inducing the neonatal rises in plasma iodothyronine concentrations in lambs. tsh levels rose during the first 4 to 8h of life, whereas plasma t4 an t3 concentrations increased only from birth to respectively 2 and 1h; the rise in free t4 levels was longer and more important than the rise in total t4. only t4 changes were strongly related to the extent of tsh increase. the neonatal tsh surge was inhibited by delaying the first milk intake ...19902118150
[construction of echinococcus granulosus genomic library].using embl3 phage dna as a vector, a perfect genomic library of echinococcus granulosus from sheep from xinjiang has been constructed, which contains 1.2 x 10(6) independent recombinants. the main procedure of construction comprised: 1. extraction of echinococcus granulosus genomic dna, 2. partial digestion of the extracted e. granulosus genomic dna with restriction enzyme sau3al, 3. harvest of 15-23 kb dna fragments by electric elution equipment, 4. preparation of embl3 phage vector dna, 5. cle ...19911873893
effects of short and long duration hypothyroidism and hyperthyroidism on the plasma adrenocorticotropin and corticosterone responses to ovine corticotropin-releasing hormone in rats.we report here a study of the plasma acth and corticosterone responses to synthetic ovine crh (ocrh) in hypothyroid and hyperthyroid rats studied 7, 15, and 60 days after either thyroidectomy or the administration of pharmacological doses of t4. the purpose of this study was to further clarify the time-dependent effects of alterations in thyroid status on the functional integrity of the hypothalamic-pituitary-adrenal axis and to aid in the interpretation of the ocrh stimulation test in hypo- and ...19911850357
lymphocyte subpopulations in peripheral blood of lambs experimentally infected with bovine respiratory syncytial virus.the lymphocyte subpopulations of peripheral blood of normal lambs and lambs experimentally infected with bovine respiratory syncytial virus (rsv) were analysed by flow cytometry, using a panel of monoclonal antibodies against specific lymphocyte epitopes. experimental infection with bovine rsv was characterized by a significant rise in sbu-t8+ (cd8+ or cytotoxic) t cells and a significant reduction in sbu-t4+ (cd4+ or helper) t cells and b (lca p220+) lymphocytes (p less than 0.05). the helper/s ...19902140217
in vivo effects of trh, t3 and cgh on antibody production and t- and b-lymphocytes proliferation in immature male chickens.newly hatched white leghorn male chicks were used in this study. different doses of t3 (0.1 or 1 ppm) or trh (1 or 5 ppm) were administered in the feed for an 8-week period. chicken growth hormone (cgh) (10 micrograms/kg bw) was injected (i.v.) into a different group of chicks twice daily for 1 week starting at 7 weeks of age. a different group received both t3 (0.1 and 1 ppm) and cgh. serum concentrations of t4, t3 and gh, antibody production against sheep red blood cells (srbc) and brucella ab ...19911757115
[the effect of synchronization on estrus and pregnancy in sheep and on levels of thyroxine, triiodothyronine, 17 beta-estradiol, progesterone and cholesterol].knowledge of pathogenesis of sexual dysfunctions at altered thyroid activity is limited by the knowledge of multiple and ubiquitous action of its hormones throughout the organism. one of the possibilities of modulatory influence of thyroid hormones on sexual functions can be realized through the participation of thyroxine and triiodothyronine in the synthesis and metabolism of primary substrate of steroid synthesis--cholesterol. the presented work is aimed at the study of simultaneous dynamic ch ...19911724714
endometrial t-lymphocyte subset infiltration during the ovine estrous cycle and early pregnancy.t-lymphocytes were quantitated within luminal, stromal and glandular areas of ovine endometrium. in experiment 1, ovariectomized (ovx), estrus (e) and day 13 (d13) ewes (six/group) received 500 micrograms of phytohemagglutinin (pha) or vehicle in ligated right and left uterine horns, respectively. at 48 h, uteri were removed for the immunohistochemical evaluation of t-lymphocyte subsets. in experiment 2, t-lymphocytes were quantitated within non-pregnant and pregnant uterine horns on day 19. for ...19911720461
lymphocyte subpopulations in peripheral blood of lambs experimentally infected with pasteurella haemolytica.the lymphocyte subpopulations in peripheral blood obtained from eleven lambs experimentally infected with pasteurella haemolytica were compared with those obtained from eight control lambs by flow cytometry, using a panel of monoclonal antibodies against specific lymphocyte epitopes. experimental infection with p. haemolytica was characterized by a transient but significant reduction in sbu-t1+ (cd5+) t cells and sbu-t4+ (cd4+ or helper) t lymphocytes (p less than 0.05) and a significant rise in ...19911712143
substance p increases and prolongs increased output of t4 (cd4) lymphocytes from lymph nodes of sheep in vivo: is it a mediator of immunological memory?there are receptors on lymphocytes for substance p which are found both on small recirculating and on blast lymphocytes. the principal effect of substance p on lymphocytes appears to be a stimulating one, both in vitro and in vivo. the in vivo administration of substance p to sheep by acute infusion into cannulated afferent lymphatics of peripheral lymph nodes has been found to stimulate efferent lymph flow and the output into efferent lymph of both small recirculating and blast lymphocytes. we ...19901705249
acute and chronic hormone and metabolite changes in lambs fed the beta-agonist, cimaterol.the objective of this study was to determine if acute and chronic changes in circulating metabolic hormone and metabolite concentrations are associated with beta-agonist-induced nutrient repartitioning in young growing lambs. two groups of 12 dorset and dorset-finn cross ram lambs weighing 36 or 33 kg live weight were assigned to 3- or 6-week treatment intervals, respectively, to achieve similar slaughter weights. six lambs within each treatment interval were fed ad libitum a complete mixed high ...19911686222
human and ovine lentiviral infections compared.maedi-visna virus (mvv) of sheep was the first lentivirus to be isolated. the genomic organization of mvv is very similar to that of human immunodeficiency virus (hiv) with several genes regulating the expression of the viral genome. viral replication is severely restricted in the host and some cells apparently contain the genetic information in a dna provirus form with little or no expression of viral antigens. this seems to be a major factor in causing the "slowness" of lentiviral infections a ...19911684142
food deprivation suppresses stress-induced rise in catabolic hormones with a concomitant tendency to potentiate the increment of blood glucose.the organism of a food-deprived animal is directed toward minimizing energy expenditure and plasma levels of catabolic hormones and glucose are also reduced. stress, on the other hand, is associated with enhancement of metabolic processes, elevated plasma catabolic hormones, and higher glucose levels. the question arises as to whether food deprivation may be able to attenuate the rise of plasma catabolic hormones seen in stress. for this purpose the variations in triiodothyronine (t3), thyroxine ...19902075204
parathyroid gland hormones in the skeletal development of the ovine foetus: the effect of parathyroidectomy with calcium and phosphate infusion.it has been confirmed that the foetal parathyroid glands are important in development and that thyroparathyroidectomy (txptx) of the ovine foetus with thyroxine (t4) replacement leads to hypocalcaemia, retarded skeletal development, depressed calcification and rickets, relative to thyroidectomy plus t4 replacement. histomorphometric and biochemical (urinary excretion of deoxypyridinoline) indices of bone resorption are also reduced. however, skeletal calcification can be restored to normal by lo ...19921576487
influence of experimental hyperthyroidism on insulin action in growing sheep.the effects of moderate hyperthyroidism on insulin action were studied in five growing sheep (42 kg live weight [lw]) by the euglycemic hyperinsulinemic clamp technique, with insulin infused at rates of 0.33, 1.00, and 6.00 mu/kg lw/min over successive 2-hour periods. animals were injected with saline (control) or thyroxine (15 micrograms/kg lw/d) for 21 days and measurements performed during the final 7 days of each period. thyroxine (t4) treatment elevated plasma t4 less than threefold and pla ...19921542262
identification of thyroxine-sulfate (t4s) in human serum and amniotic fluid by a novel t4s radioimmunoassay.recently, we identified significant amounts of thyroxine sulfate (t4s) in fetal sheep serum, meconium, bile, and amniotic and allantoic fluids. little is known, however, about sulfate conjugation of thyroxine in humans. in this study, we employed a novel, sensitive t4s ria to address this question. the rabbit antiserum was quite specific; t4, t3, rt3, and 3,3'-t2 showed less than 0.002% cross-reactivity. other analogs cross-reacted less than 0.0001%. only rt3s and t3s cross-reacted significantly ...19921525576
[use of a protein-free medium for the in vitro development of sheep embryos].the employment of protein-free medium for the culture of ovine embryos collected at the 1-2 cell stage from superovulated ewes was investigated. for this purpose sheep zygotes were randomly allocated in four treatment groups: t1) czb medium + bovine serum albumin (bsa) on sheep oviductal monolayer (som), t2) czb + polyvinyl alcohol (pva) + som, t3) czb + pva + som supplemented with inositol (i) and serine (s), t4) tcm 199 + 10% fetal calf serum + som. standard culture conditions were 2 ml of med ...19921457098
[the effect of repeated administration of carbetocin (depotocin, spofa) in the first days postpartum on levels of thyroxine, triiodothyronine, 17 beta-estradiol, progesterone and on fertilization].application of new procedures in the sphere of the control of sexual functions requires an extension of present knowledge of postparturient endocrinium or endogenic factors comprised in postparturient physiology of sexual activity. according to recent data, oxytocin, besides its uterotonic and luteolytic activity, acts as an ovarian factor in the local intrafollicular regulation of stereidogenesis and as a modulator of uterine secretion of prostaglandines. based on present knowledge of oxytocin ...19921413401
thyroxine sulfate is a major thyroid hormone metabolite and a potential intermediate in the monodeiodination pathways in fetal sheep.t3 and rt3 production rates in the fetus account for roughly only a third of the total t4 production rate; thus, the fate of the majority of t4 produced in the fetus is unknown (the "t4 disposal gap"). we developed sensitive and specific t4 sulfate (t4s) and t3 sulfate (t3s) rias to investigate the roles of these compounds in fetal t4 metabolism. t3, t4, t3s, and t4s were determined in a variety of tissue fluid and/or serum samples obtained from fetal, newborn (n = 6), and adult (n = 6) sheep. f ...19921396320
regulation of thyroid hormone synthesis in cultured ovine thyroid follicles.primary cultures of sheep thyroid follicles were used to study the regulatory control mechanisms of thyroid hormone production. when maintained under serum-free conditions in vitro these follicles exhibit hormone-dependent iodide transport, iodine organification, and physiological de novo thyroid hormone formation. in previous studies we have also shown that thyroid follicles condition their culture media with insulin-like growth factors (igfs) and igf-binding proteins which are of potential aut ...19921315258
immunoelectron microscopy of cell populations in regional and central lymph of sheep.the immunoreactivity and the ultrastructural localization of monoclonal anti-sheep lymphocyte antibodies conjugated with colloidal gold particles were examined in free-floating cells of sheep central lymph from the thoracic duct, postnodal lymph draining either the popliteal nodes or the mesenteric nodes, and prenodal lymph draining the pregnant uterus. the monoclonal antibodies used in this study were sbu-t1 (cd5), sbu-t4 (cd4), sbu-t8 (cd8), sbu-ii (anti dr antibody), and e53 which are reporte ...19911921477
[effect of the sudden removal of lambs on the blood levels of prolactin, triiodothyronine and thyroxine in ewes].the effect of the sudden removal of lambs, average age 42 days (36 to 54), on the blood level of prl, t3 and t4 was checked, using a radioimmunological method, in 18 sardinian ewes that had lambed in november (10 treated and 8 control). the two groups of animals, reared indoors in different sheep-folds, were subjected to the same management and feeding. compared to day before the removal of the lambs, the blood prl showed a sharp decrease which lasted 24 hours. after 4 days of observation, despi ...19911888485
[dynamics of changes in the serum levels of cholesterol, thyroid and ovarian hormones in the postpartum period in ewes].postparturient anoestry, spontaneously changing over to seasonal anoestry, represents an important reserve of full utilization of the reproductive potential of sheep. in spite of the fact that the length of gestation in sheep only amounts to 148 days (+/- 5 days), inability of most sheep to enter the cycle during the spring season acts as a factor limiting the number of lambings--and at the same time production of lambs--to one lambing per year. in order to obtain more detailed knowledge of horm ...19911841478
preferential release of tri-iodothyronine following stimulation by thyrotrophin or thyrotrophin-releasing hormone in sheep of different ages.the influence of trh and tsh injections on plasma concentrations of tri-iodothyronine (t3) and thyroxine (t4) was investigated in neonatal (injection within 0.5 h after delivery) and growing lambs and in normal, pregnant and lactating adult ewes (all 2 years old and originating from suffolk, milksheep and texal crossbreeds). neonatal lambs had higher levels of t3, t4 and gh compared with all other groups, whereas prolactin and tsh were higher in lactating ewes. in all animals, injections of trh ...19921737964
saturable uptake of [125i]l-triiodothyronine at the basolateral (blood) and apical (cerebrospinal fluid) sides of the isolated perfused sheep choroid plexus.the uptake of 125i-labelled l-triiodothyronine (t3) was measured on the blood side of the isolated perfused choroid plexus of the sheep using steady-state and single-circulation paired tracer techniques. the steady-state uptake of t3 was 33.5% (perfusion fluid protein content was 0.05 g.dl-1) which could be reduced to 9.4% in the presence of 500 microm unlabelled t3 showing partial saturation. the csf to blood steady-state [125i]t3 measurements gave plasma/csf ratio, r%, of 24.6 +/- 4.8% which w ...19921450924
lipopolysaccharide heterogeneity in pasteurella haemolytica isolates from cattle and sheep.lipopolysaccharide (lps) from 40 isolates of pasteurella haemolytica, comprising 23 serotype a1, seven serotype a2, one serotype t4, one serotype t10 and eight untypable isolates, obtained from diseased and healthy cattle or sheep, was characterized by sds-page and western blotting. ten different sds-page lps profiles, five smooth and five rough, were identified among the biotype a and untypable isolates and designated lps types 1-10. lps types 1 and 2 were smooth, had similar o-antigen banding- ...19921282533
effects of thyroid hormones on humoral and cell-mediated immune responses in the domestic fowl (gallus domesticus).we investigated the effect of raising and lowering circulating thyroid hormones in young domestic fowl on antibody production and the responses of peripheral blood lymphocytes (pbl) to the mitogens concanavalin a (con a) and phytohaemagglutinin (pha). circulating thyroid hormones were reduced by treatment with the goitrogen, methimazole, and raised by giving implants containing thyroxine (t4) and/or triiodothyronine (t3). raising or lowering circulating thyroid hormones had no significant effect ...19902120091
[effects of thyroxine on igm production and beta-adrenergic receptor on lymphocyte in mice].the effects of thyroxine (l-t4) on the igm production of splenocytes in mice induced by sheep red blood cell (srbc) were investigated by means of spectrophotometry of quantitative hemolysis (qhs). the maximum binding site number (bmax) and affinity (kd) of beta-adrenergic receptors (beta-adr. r.) on splenic lymphocytes of mice under the different thyroid functional status during immune response were determined by radio-ligand combination method. the igm production and bmax of beta- adr. r. of sp ...19902177571
inflammatory cell and immune function in merino sheep with chronic dermatophilosis.components of inflammatory and immunological responses were compared in 17 merino sheep with chronic dermatophilosis (group 1) and 15 merino sheep that had recovered from the disease (group 2). the functions studied included: (i) total and differential white cell counts; (ii) phagocytic function and intracellular killing by neutrophils; (iii) humoral immune response to t-dependent and t-independent antigens and to dermatophilus congolensis. (iv) lymphocyte blastogenic responses to phytohaemagglu ...19892623798
[influence of the season and of gestation on the plasma concentration of thyroid hormones: triiodothyronine (t3) and thyroxine (t4) in sahel peulh ewes].seasonal and gestational variations of triiodothyronine (t3) and thyroxine (t4) plasma concentrations were evaluated in 12 pregnant and 6 non pregnant adult sahel peulh ewes. blood samples were drawn from all animals at different dates for radio-immunoassay. in this particular breed of sheep, plasma triiodothyronine and thyroxine levels did not present significant variations from the beginning of the cool season (december) until the end of the dry warm season (may). on the contrary, a highly sig ...19902288455
acute endotoxin-induced lymphocyte subset sequestration in sheep lungs.endotoxemia is associated with an early phase of pulmonary hypertension and a later increase in microvascular permeability. these physiologic changes are attended by peripheral blood and lung lymph leukopenia and a rapid accumulation of both granulocytes and lymphocytes in the peripheral lung. in the present study, the numbers of lymphocytes in blood, lung lymph, and lung tissue after infusion of endotoxin were determined by fluorescent labeling of lymphocyte populations with monoclonal antibodi ...19902179624
thymocyte subpopulations during early fetal development in sheep.phenotypic analysis of thymocytes during fetal development may identify subpopulations which are either absent or difficult to detect in postnatal thymus. a panel of monoclonal antibodies specific for sheep lymphocyte antigens (sbu-t1, -t4, -t8, -t6) was used to identify thymocyte subpopulations in postnatal and fetal sheep. thymuses were analyzed by two-color immunofluorescence and flow cytometry or by immunohistology. two-color immunofluorescent staining of postnatal sheep thymus with anti-sbu ...19862419408
two pathways for thyroxine 5'-monodeiodination in brown adipose tissue in fetal sheep: ontogenesis and divergent responses to hypothyroidism and 3,5,3'-triiodothyronine replacement.thermogenesis in rat brown adipose tissue (bat) is thyroid hormone responsive. rat bat expresses a type ii 5'-iodothyronine monodeiodinase (5'mdi) which mediates local t3 production from t4. earlier studies show that bat from fetal and newborn sheep contains a high km type i, instead of type ii, 5'mdi. to better characterize the 5'mdi of ovine fetal bat, we studied the in vitro monodeiodination of [125i]t4 at a low substrate concentration (2 nm) and in the presence of 1 mm propylthiouracil in ba ...19902318152
thyrotropic activity of the ovine corticotropin-releasing factor in the chick embryo.an injection of several doses of ovine corticotropin-releasing factor (ocrf) was made into an allantoic blood vessel of 18-day-old chick embryos. all doses used (0.5, 1, 2, and 5 micrograms) induce a quick increase of plasma corticosterone concentrations after 15 and 30 min and 1 and 2 hr and this in a dose-dependent manner with the high doses having a prolonged effect lasting up to 2 hr. an increase in plasma levels of thyroxine (t4) and triiodothyronine (t3) was observed after 1 and 2 hr. afte ...19892555247
the effects of bovine growth hormone and thyroxine on growth rate and carcass measurements in lambs.the effects of bovine growth hormone (gh) and thyroxine (t4) on growth and carcass characteristics were assessed in dorset ram lambs. lambs in four groups (n = 10/group) were treated for 30 d as follows: controls, 3.33 mg (6 iu) gh/d (s.c.); 5-mg t4 implant (s.c.) on d 1 and a 10-mg t4 implant 21 d later; gh + t4. blood samples were collected at 3-d intervals for analysis of gh, t4, triiodothyronine, somatomedin-c and testosterone concentrations. six lambs/group were slaughtered for carcass meas ...19892613578
observations on blood leucocytes and lymphocyte subsets in sheep infected with bovine leukaemia virus: a progressive study.haematological parameters and reactivity of lymphocyte antigens to monoclonal antibodies were studied over a 10-month period in sheep experimentally infected with bovine leukaemia virus (blv). blv-inoculated animals seroconverted within 1 month and showed a significant lymphocytosis 2-6 weeks after infection. control animals inoculated with blv-free lymphocytes showed a stronger and more immediate neutrophil response than those inoculated with blv-positive lymphocytes. one month after infection, ...19892559536
unusual features of neonatal thyroid function in small-for-gestational-age lambs. origin of plasma t4 and t3 deficiencies.thyroid function was studied in small for gestational age (sga) or control newborn lambs. neonatal changes in plasma concentrations of tsh, t3, rt3, total and free t4 were monitored, and thyroid scintigraphs were performed. responsiveness of the hypothalamic-pituitary-thyroid axis to cold exposure and trh or tsh administration was assessed. in addition, t4 and t3 kinetic studies were performed. in agreement with results obtained in babies, plasma t3, total t4 and free t4 concentrations were depr ...19902128704
relationship between the thyroidal and gonadal axes during the estrous cycle of ewes of different breeds and ages.in order to define the patterns of tsh, t4, t3, rt3, gh and cortisol during the estrous cycle of sheep, pluriparous and primiparous ewes were synchronized with progestagen-impregnated pessaries (veramix) at the start of the normal breeding season. after the pessaries were removed (day 0), daily blood sampling was carried out in cannulated ewes during the ovulatory cycle. hormonal analyses of tsh, t4, t3, rt3, gh, cortisol, lh and progesterone (p) were performed by ria. p and lh levels during the ...19892590387
ficoll-hypaque leukocyte preparations from burned patients contain activated nonlymphoid cell populations that take up thymidine.previously, we reported that ficoll-hypaque-purified leukocytes from burned patients were activated in vivo, even when the mitogen response of these cells was depressed. in these patients, the sbt (endogenous blastogenesis), but not the mitogen response predicted sepsis. the current experiments were performed to clarify why the sbt is increased even when mitogen-stimulated blastogenesis is impaired. we found that neither selective lymphocyte subpopulation (okt3, t4, t8), nor macrophage depletion ...19892784506
alterations of human growth hormone binding by rat liver membranes during hypo- and hyperthyroidism.hypothyroid rats treated with human gh (hgh) were partially refractory to the latter's effects. the present study was undertaken to investigate the role of hypo- and hyperthyroidism on the gh receptor. seven-week-old rats were rendered either hypothyroid, by methimazole, or hyperthyroid, by a daily overdose of t4, during weeks 7-14 of life. livers were homogenized and overlaid on sucrose discontinuous density gradient. removal of endogenous ligand from the receptor was performed by exposing the ...19902293991
effects of alpha-ketoisocaproate on adrenocorticotropin-induced suppression of lymphocyte function in sheep.previous studies of the amino acid analogue, alpha-ketoisocaproate (kic), indicate that it can stimulate lymphocyte blastogenesis and antibody responses of sheep. to determine whether kic could overcome the effects of adrenocorticotropic hormone (acth)-induced lymphocyte suppression, 24 lambs were fed a control diet, a diet supplemented with 0.05% kic, or a diet supplemented with 0.05% of the parent amino acid leucine. immune status was monitored by determining lymphocyte blastogenic responsiven ...19911674650
thyroid hormone and growth: relationships with growth hormone effects and regulation.for some years, research in the field of growth endocrinology has been mainly focused on growth hormone (gh). however, it appears that gh does not always control growth rate. for instance, it does not clearly influence intra-uterine growth: moreover, although the results of grf or gh administration appear convincing in rats, pigs or heifers, this is not the case in chickens and lambs. in addition, gh does not always clearly stimulate somatomedin production, particularly diring food restriction a ...19892514702
the effect of cortisol on thyroid hormone kinetics in the ovine fetus.the mechanism underlying the association of rising concentrations of circulating triiodothyronine (t3) with the prepartum surge in the concentration of cortisol was investigated in 11 fetal sheep. the concentrations and metabolic clearance rates of t3 and thyroxine (t4) were measured prior to and following a continuous intravascular infusion of cortisol (1 mg/h for 84 h). mean plasma t3 concentrations increased 10-fold following cortisol infusion whereas the concentrations of t4 either remained ...19892607090
pituitary-thyroid axis sensitivity and neonatal changes in plasma iodothyronine, thyreostimulin and cortisol levels in the preterm lamb: comparison of two experimental models.the influence of a 7 days prematurity, induced by oestrogen or dexamethasone injection to the mothers, on neonatal changes in plasma t4, t3, reverse t3 (rt3), tsh and cortisol levels was studied in 6 full term, 6 oestrogen preterm and 6 dexamethasone preterm lambs. in addition, the pituitary-thyroid axis sensitivity was assessed by the magnitude of the response to trh administration. at birth, plasma cortisol and t3 levels, as the value of the t3/t4 ratio, were significantly lower in the two gro ...19892515221
influence of experimental acidosis on the concentrations of thyreostimulin (tsh) and iodothyronines (total t4, free t4, t3) in the plasma of the newborn lamb.the effects of acute acidosis on neonatal thyroid function were studied by infusing hcl for 4 h in 42 to 54-h-old lambs. animals of the same age, used as controls, were simultaneously infused with physiological saline. hcl infusion induced a sharp decrease in blood ph and total restoration did not occur before 48 h. when compared to control lambs, this experimental acidosis was associated with slight, but significant, decreases in plasma tsh, total t4, free t4 and total t3 levels, and in values ...19892610873
energy expenditure associated with sodium/potassium transport and protein synthesis in skeletal muscle and isolated hepatocytes from hyperthyroid sheep.the object of the present study was to determine the effect of thyroxine (t4) treatment of sheep on protein synthesis and associated energy costs in skeletal muscle and hepatocytes. protein synthesis, and ouabain-sensitive and cycloheximide-sensitive respiration in isolated intercostal muscle and hepatocytes were determined in sheep after 5 weeks of daily injections of either saline or t4. plasma t4 and total triiodothyronine (t3) concentrations were doubled and free t3 concentrations were quadr ...19892557888
influence of tri-iodothyronine or lipid administration on the response of the pituitary-thyroid axis to exposure to cold in the newborn lamb.the influence of the administration of tri-iodothyronine (t3) or a solution of soya oil and egg lecithin on the response of the pituitary-thyroid axis to moderate exposure to cold (4 degrees c for 4 h) was studied in 24-h old lambs. in control lambs, plasma concentrations of tsh. t3 and total and free thyroxine (t4) rose significantly whereas plasma concentrations of reverse t3 remained unchanged during the test. in lambs injected i.v. with a small amount of t3 (1.23 nmol/kg) 30 min before the o ...19892754368
protein and carbohydrate structural analysis of a recombinant soluble cd4 receptor by mass spectrometry.the primary structure of a soluble form of the cd4 receptor (scd4) expressed in chinese hamster ovary cells has been confirmed by mass spectrometric peptide mapping and and tandem mass spectrometry. these studies corroborated 95% of the 369-amino acid-long sequence and established the fidelity of translation of the nh2 and cooh terminal including the absence of "ragged ends." the arrangement of the three disulfide bonds in recombinant scd4 was also established by mass spectrometry and comparativ ...19892592374
seasonal variations in prolactin, growth hormone and thyroid hormones and the prolactin surge at ovulation do not affect litter size of ewes during pregnancy in the oestrous or the anoestrous season.injection of bromocriptine from 5 days before until 5 days after mating clearly suppressed the periovulatory prolactin surge in ewes in the anoestrous and oestrous season but did not change the litter size significantly. progesterone, gh, tsh or thyroid hormone concentrations were not influenced by the bromocriptine treatment. the progesterone concentrations were lower during the first weeks after mating in the anoestrous season compared to the oestrous season, while there was no difference betw ...19902231554
[mechanisms of the lactogenic action of thyroid hormones and nonspecific resistance in ruminants].studied was the effect of thyroid hormones on the nonspecific resistance and the milk productivity of ruminant animals in the conditions of hypodynamia and in various functional conditions of the thyroid gland. both the removal of the thyroid gland (thyroidectomy) and the hypofunction of the gland (as induced by ammonium perchlorate at 10 mg/kg body mass) were accompanied by the drop of the indices characterizing the nonspecific resistance of the animals as well as their milk productivity. the i ...19872820116
the role of thyroid hormones in maturation of the adrenaline-sensitive lung liquid reabsorptive mechanism in fetal sheep.1. following thyroidectomy at 106-118 days fetal sheep were infused continuously with triiodothyronine (t3) from 110, 118, 125 or 131 days (n = 12) or with thyroxine (t4) from 118 days (n = 4) until the fetuses were delivered. lung liquid secretion or absorption rates, heart rate, blood pressure and arterial blood gases were measured before and during 45 min periods of fetal infusions of adrenaline (n = 60) at 3-8 day intervals. the effects of t3 or t4 replacement on the response to adrenaline w ...19902391659
antioxidants delay the onset of thyroiditis in obese strain chickens.dietary iodine has been shown to be important in the induction of thyroiditis in susceptible chicken strains although the underlying mechanism remains unknown. iodine may exert its effects through the formation of reactive oxidative radicals which would cause thyroidal injury and initiate infiltration. we have tested this hypothesis by examining the ability of butylated hydroxyanisole (bha), ethoxyquin, and other antioxidants to prevent thyroiditis in obese strain (os) chickens, a strain that de ...19902401227
isolation of highly purified lymphocyte subsets for functional studies by means of an indirect rosette technique.an indirect rosette assay, utilizing ox erythrocytes (rbc) coupled with rabbit anti-mouse igg and lymphocytes sensitized with monoclonal mouse antibodies against membrane markers, was used for purification of lymphocyte subsets that were functionally intact. either peripheral blood mononuclear cells (pbmc) or t lymphocytes isolated by sheep rbc rosetting could be used as starting material for obtaining pure t-cell subsets (t4 or t8). the following steps of the method were evaluated: the procedur ...19852992071
demonstration of t4, t8, m1 and b7 determinants on human t cells with a rosette test: implications for the assay specificity of monoclonal antibodies.under optimal test conditions significantly more freshly isolated human t cells reacted with okt4, okt8, okm1 and okb7 monoclonal antibodies (mabs) in the indirect antiglobulin rosetting reaction (iarr) than by indirect immunofluorescence. rabbit erythrocytes (e) coated with anti-mouse immunoglobulin were more sensitive indicator cells in the iarr than similarly coated sheep e. treatment of t cells with neuraminidase further enhanced t cell reactivity in the iarr with each mab so that an average ...19852413129
some properties of dendritic macrophages from peripheral lymph.peripheral lymph was collected from the skin and liver of sheep, and from the intestine of rats. the dendritic macrophages contained in it were isolated by centrifuging the lymph over a layer of 'nycodenz'. similar cells were produced by culturing mononuclear cells from venous blood, but the yields were very small. the numbers of dendritic cells in the lymph from the legs of sheep increased five-fold after xylene had been applied to the skin. dendritic macrophages displayed abundant class ii his ...19892807381
the effect of thyroxine, 3, 5-dimethyl-3'isopropyl-l-thyronine and iodized oil on fetal brain development in the iodine-deficient sheep.studies have been carried out to investigate the role of maternal and fetal thyroid function in the effects of iodine deficiency on fetal brain development in sheep. iodine deficiency was established with an especially prepared low-iodine diet of maize and pea pollard. the iodine-deficient sheep were mated and the end of the second trimester of pregnancy (100 days gestation) were divided into groups which received either a sc injection of t4 or 3,5-dimethyl-3-isopropyl-l-thyromine or an injectio ...19892545065
adenosine induced production of a soluble factor affecting lymphocyte activation.we show that a brief exposure of human peripheral blood mononuclear cells (pbmc) to adenosine or to theophylline results in a mitomycin c resistant regulatory activity. adenosine induced suppression is also detectable in a lymphocyte subpopulation (t4+ enriched, originally described as helper inducer) resistant to the theophylline induced loss of capacity to form spontaneous rosettes with sheep erythrocytes (ttr). this activity is apparently dependent on the production of a soluble factor(s) sin ...19862876953
effect of two thymosin fraction 5 polypeptides on human peripheral blood lymphocytes.thymosin fraction 5 polypeptides beta 4 and alpha 1 were tested for their ability to affect certain immunological parameters of human peripheral blood lymphocytes (pbl). pbl were cultured with various concentrations of the peptides for 24 hours. thymosin beta 4 was found to induce a significant decrease in the expression of the fc alpha receptors of pbl, as well as in their ability to express antibody dependent cellular cytotoxic (adcc) activity. in addition, this peptide had the ability to incr ...19872893819
iodine nutrition in ewes. 2. effects of low to high iodine intake by ewes on the i content of biological fluids and plasma immunoglobulins g in newborn lambs.1. in two experiments samples of blood and organs were taken from newborn and young lambs born to five groups of ewes that received different dietary iodine (i) levels. dietary i contents (mg/kg dry matter [dm]) in pregnancy and lactation, respectively, were: experiment 1--0.36 and 0.26 for group c, 2.01 and 1.94 for group d; experiment 2--0.13 and 0.12 for group a, 0.22 and 0.20 for group b, 10.77 and 8.88 for group e. 2. i intake of ewes had no effect on birthweight, body weight gain, or morta ...19892757760
the effect of thyroidectomy in the fetal sheep on lung liquid reabsorption induced by adrenaline or cyclic amp.1. in fetal sheep at 113-120 days' gestation, thyroidectomy was performed and tracheal, arterial and venous catheters inserted. following a recovery period experiments were performed from 120-145 days to measure changes in lung liquid secretion or its absorption in response to i.v. adrenaline infusion or to introduction of dibuteryl cyclic amp into lung liquid. the results were compared with those previously obtained in non-thyroidectomized fetuses. 2. plasma levels of thyroid hormones in non-th ...19882855741
human cord blood suppressor t lymphocytes. ii. characterization of inducer of suppressor cells.previously, we reported an antigen nonspecific inducer of t suppressor cell factor (tisf) produced by cord blood mononuclear cells (mnc) in 48-hr, two-way mixed lymphocyte cultures (mlc). the target of this factor was a radiosensitive, t4+ (t8-) adult suppressor t cell subset. the cellular origin of this tisf was examined in the present study. igg production by pokeweed mitogen (pwm)-stimulated adult mnc was used as an assay for tisf activity. it was found that tisf-producing cells formed rosett ...19862943171
immune responses during human schistosomiasis mansoni. xiii. immunological status of spleen cells from hospital patients with hepatosplenic disease.splenocytes from 25 patients with severe hepatosplenic schistosomiasis mansoni were obtained after therapeutic splenectomy. spleen cells were phenotyped and analysed for responsiveness to mitogens or heterogeneous schistosome-derived antigenic preparations (eggs, sea; adult worms, swap; cercariae, cerc) in blastogenesis assays and lymphokine production systems, and were compared with peripheral blood mononuclear cells (pbmn). splenic lymphocytes were 55% t lymphocytes (sheep erythrocyte rosette- ...19863094136
[interhormonal relations in the dynamics of immune response during thyroidectomy].wistar rats were immunized with the sheep erythrocytes (se) within 18 or 60 days after thyroidectomy. the latter led to a sharp drop in concentration of t3, t4 and to 2-3-fold increase in the tth level. the se administration failed to induce an increase in the t3, t4 level in operated animals whereas the tth concentration increased. during the inductive period of immunogenesis a reduction occurred in the antigen-induced glycocorticoid response and the testosterone level in the early period repla ...19892924963
chronic t cell leukemia with unusual cellular characteristics in ataxia telangiectasia.a 27-year-old male patient with ataxia telangiectasia (at) developed atypical chronic lymphocytic leukemia with increasing bone marrow infiltration in the absence of organomegaly. one-third of the leukemia cells expressed a mature suppressor/cytotoxic t cell phenotype (t3+ t4- t6- t8+ t10-), two-thirds demonstrated additional helper/inducer t cell-associated antigens (t3+ t4+ t6- t8+ t10-), and a small fraction reacted with a natural killer (nk) cell-specific monoclonal antibody (leu 11+). the p ...19862942200
hypophysectomy of the fetal lamb leads to a fall in the plasma concentration of insulin-like growth factor i (igf-i), but not igf-ii.the role of the pituitary gland in the regulation of the plasma concentrations of insulin-like growth factors (igfs) in the late gestation sheep fetus has been examined. singleton sheep fetuses were either hypophysectomized or sham-operated between days 110-120 of gestation. blood samples were then collected via carotid cannulae at least three times weekly for the remainder of gestation. in some hypophysectomized fetuses t4 was administered (100 g/day) to overcome the hypothyroidism caused by hy ...19892917521
the endocrine and metabolic response to feeding in the developing lamb.oxygen consumption (vo2), carbon dioxide production (vco2), heart rate and the arterial plasma concentrations of glucose, non-esterified fatty acids, thyroxine (t4), 3,5,3'-tri-iodothyronine (t3), tsh, insulin, cortisol and gh were measured before and after feeding a formula milk diet to lambs aged 9, 21, 33 and 46 days. in all age groups, vo2, vco2 and heart rate increased significantly following feeding and this effect was greatest at 9 days of age. both vo2 and vco2 before and after feeding d ...19892514244
neutralization of t-replacing factor by t8-positive lymphocytes: an important suppressor mechanism operating in the regulation of polyclonal b-cell activation.pokeweed mitogen (pwm)-induced b-cell activation was entirely abrogated by pre-treating peripheral mononuclear cells (pbm) with t4 (anti-t-helper-inducer subset) or t11 (anti-sheep erythrocyte receptor, ie. anti-pan-t-cell) monoclonal antibody plus complement. immunoglobulin secretion was restored in t11- but not t4- cultures by adding the culture supernatant from pwm-stimulated pbm (t-replacing factor, trf). since t8+ (t-suppressor-cytotoxic subset) cells were present in high concentrations in ...19852934189
lymphocyte proliferation induced by autologous cells. xv. relationships between the human autologous mixed lymphocyte reaction stimulated by non-t and activated t cells.the human (t:t act) amlr was characterized in its relationship to the (t:non-t) amlr and its validity as a nonxenogeneic antigen induced response was extended. human t cell lines, established from responding t cells in an autologous mixed lymphocyte reaction (mlr), were maintained in medium containing human serum and interleukin-2 (il-2). these cells stimulated 3h-thymidine incorporation by autologous t cells and by autologous unfractionated blood mononuclear cells. freshly activated t cells iso ...19852934354
molecular cloning and expression of t11 cdnas reveal a receptor-like structure on human t lymphocytes.the t11 (cd2) sheep-erythrocyte-binding protein is a t-cell surface molecule involved in activation of t lymphocytes and thymocytes, including those lacking the t3-ti antigen-receptor complex. the primary structure of t11 was deduced from protein microsequencing and cdna cloning. the mature human protein appears to be divided into three domains: a hydrophilic 185 amino acid external domain bearing only limited homology to the t-cell surface protein t4 and the immunoglobulin kappa light chain var ...19872883656
phenotypic properties of atypical lymphocytes in cytomegalovirus-induced mononucleosis.the phenotypic properties of the surface of the atypical lymphocytes seen in cytomegalovirus-induced (cmv) mononucleosis were evaluated. mononuclear cells from peripheral blood were obtained from adult patients within seven to 35 days of the onset of acute cmv mononucleosis. sheep red blood cell rosetting techniques were used to obtain populations depleted of, or enriched for, t cells. cell populations were further purified for helper/inducer lymphocytes (t4), cytotoxic/suppressor lymphocytes (t ...19852989382
human thymic dendritic cells. characterization, isolation and functional assays.the phenotypic analysis of human thymic dentritic cells (dc) in culture and in purified suspensions has been studied with light and electron microscopic (em) immunolabelling techniques. using a series of monoclonal antibodies (mab) and a protein a-gold technique, we demonstrated that dr- and t6-positive cultured dc strongly bind the 9.3f10 mab, an anti-dr-related antibody produced against human blood dc, and weakly express the t4 antigen, a membrane marker shared by langerhan's cells (lc). on th ...19882972601
iodine nutrition in ewes: effects of low to high iodine intake on iodine content of biological fluids in pregnant and lactating ewes.in a first experiment, 2 groups of 46 and 47 multiparous ewes received diets which provided an iodine intake of 0.36 and 0.26 mg/kg dry matter (group c) and, 2.01 and 1.94 mg/kg (group d), respectively, for pregnancy and lactation. in a second experiment, 3 groups of 10 nulliparous ewes received diets which provided an i intake of 0.13 and 0.12 mg/kg dry matter (group a), 0.22 and 0.20 mg/kg dry matter (group b), and 10.77 and 8.88 mg/kg dry matter (group e), respectively, for pregnancy and lact ...19892928599
effects of growth hormone administration on wool growth in merino sheep.the effects of daily administration of 10 mg of highly purified ovine growth hormone (gh) for a period of 4 weeks on wool growth have been measured in 12 merino ewes fed either a calculated maintenance energy intake or 1.6 times this amount (six on each ration). concentrations of hormones, glucose, urea, alpha-amino n and amino acids in the blood were monitored and faeces and urine collected for measurement of nitrogen balance. wool growth rate decreased by 20% during the 4 weeks of gh treatment ...19883077896
dog erythrocyte rosette-forming lymphocyte: blockage by okt11 monoclonal antibody.human peripheral blood mononuclear cells (pbm) were separated into sheep erythrocyte rosette-forming (es+) and non es+ cells by the ficoll-hypaque gradient sedimentation method. thirty-eight percent of the es+ cells formed rosettes with dog erythrocytes and were designated as es+ed+ cells. the remaining es+ cells were designated as es+ed- cells. only a few non es+ cells formed rosettes with dog erythrocytes. among es+ed+ cells, t4 antigen-positive cells were observed approximately 1.7 times as o ...19873105252
thyroid response to ovine thyrotropin challenge in cortisol- and dexamethasone-treated rainbow trout, salmo gairdneri.cortisol or dexamethasone, administered to rainbow trout (salmo gairdneri) in the form of intraperitoneal "implants" suspended in hydrogenated coconut oil, had no apparent effect on plasma total thyroid hormone levels, or plasma t3/t4 ratios. the duration of the ovine tsh-stimulated surge in plasma t4 levels was decreased and increased in fish given cortisol and dexamethasone "implants" respectively; plasma t3 levels were not affected by tsh stimulation. the level of steroids administered in the ...19872881680
the immunoregulatory nature of iron. ii. lymphocyte surface marker expression.previously, we presented preliminary evidence that supported our hypothesis for the immunoregulatory nature of iron [7]. the objective of the present work was to test that hypothesis in greater detail. our approach was to examine the effect that iron had on the expression of the surface markers on lymphocytes that had been activated by pokeweed mitogen (pwm). the two categories of lymphoid surface molecules were enumerated on those cells; first were those that identify t lymphocytes and second, ...19863095475
examination of the low proliferative capacity of human jejunal intraepithelial lymphocytes.the proliferation of human jejunal intraepithelial lymphocytes (iel) was examined to determine how it differed from that of peripheral blood (pb) t lymphocytes. the iel were mainly t lymphocytes of the cytotoxic-suppressor (t8+) phenotype. they demonstrated lower proliferative responses to various stimuli (2,501 +/- 565 ct/min with phytohaemagglutinin; pha) compared to unseparated pb t lymphocytes (73,678 +/- 2,495) or the t8+ subset (68,939 +/- 10,053 ct/min) (p less than 0.001). this low proli ...19862947761
effects of trh and grf administration on gh, tsh, t4 and t3 secretion in the lamb.the effects of various amounts of thyrotropin-releasing hormone (trh) injected subcutaneously or intravenously (alone or in combination with growth hormone-releasing factor: grf 1-44) on growth hormone (gh), thyroid-stimulating hormone (tsh), thyroxine (t4) and triiodothyronine (t3) were studied in the plasma of 2-week, 2-month and 3-month old lambs. after subcutaneous trh administration, increases in plasma tsh, t4 and t3 levels were equivalent, whatever the amount of trh used (1,2,5 or 10 micr ...19873114838
fetal plasma insulin and thyroid hormone levels during acute in utero ethanol exposure in a maternal-fetal sheep model.the effects of acute in utero ethanol (etoh) treatment on basal and stimulated thyroid and insulin levels in fetal plasma were studied in chronically cannulated fetal sheep. in test situations, pregnant ewes (0.78-0.88 gestation) which were chronically cannulated received 2 g/kg etoh [25% (vol/vol) in isotonic saline] for 2 h; this was followed by a maintenance iv infusion of 0.13 g/kg etoh. control animals received isovolemic infusions of isotonic saline. fetal arterial plasma samples were obta ...19863084206
reproductive hormone secretion and spermatogenic function in thyroidectomized rams receiving graded doses of exogenous thyroxine.this study aimed to obtain a better understanding of the relationship between circulating thyroxine (t4) concentrations and reproductive endocrine function in the ram. mature merino rams were thyroidectomized and supplemented with 0, 30, 100 and 300% of normal t4 for 10 weeks. thyroidectomy had no apparent effect on spermatogenic function but interfered with sperm maturation, the latter being returned to normal by 30% t4 replacement. circulating testosterone levels were reduced by thyroidectomy ...19863098886
immunophenotype of pulmonary cellular infiltrates in sheep with visceral caseous lymphadenitis.pulmonary lesions associated with corynebacterium ovis were analyzed with an indirect immunoperoxidase staining technique using monoclonal antibodies. the predominant cells in abscess walls and surrounding lung parenchyma were large macrophages which expressed major histocompatibility complex (mhc) class ii molecules on their surfaces. t lymphocytes were prominent in the same sites in the naturally occurring lesions, and sbu-t4-positive ("helper/inducer") cells were the major subset of lymphocyt ...19882976546
plasma renin activity, active and inactive renin concentrations, and their responses to beta 1-adrenoceptor blockade with metoprolol in hyperthyroidism.plasma renin activity (pra), plasma renin concentration (prc), inactive renin concentration (irc) and total renin concentration (trc) were measured in 31 normal controls and in 8 patients with hyperthyroidism. trc was determined as angiotensin i generated with sheep renin substrate after an acid activation of plasma. the angiotensin i of non-acidified plasma was expressed as prc. irc was calculated as trc minus prc. the mean values for pra, prc, irc and trc were significantly (p less than 0.05 t ...19863023226
[immune status of patients with bronchial cancer].the proliferation of lymphocytes, the cell-surface markers of mononuclear cells, and the capacity of t lymphocytes to bind sheep red blood cells were studied in 61 healthy volunteers and 72 patients with small-cell carcinoma, adenocarcinoma, and squamous-cell carcinoma of the lung. the mitogen-stimulated proliferation of the lymphocytes against phytohemagglutinin (pha) was significantly reduced in patients with small-cell carcinoma. the number of t lymphocytes with t3, t4, t8, and t11 receptors ...19873037180
involvement of t11 molecules in antigen receptor-mediated t lymphocyte functions: effect of anti-t11 monoclonal antibody on functional capabilities of alloreactive t cell clones.as shown by previous studies, the sheep erythrocyte-binding t11 molecule is involved in t cell activation, as well as in mechanisms of specific allogeneic target cell lysis. in this study, we utilized two anti-t11 monoclonal antibodies (mab) that inhibited the specific cytolytic activity of mixed lymphocyte culture (mlc)-activated t cells to analyze, at the clonal level, the involvement of t11 molecules in (a) antigen-specific vs. nonspecific mechanisms of target cell lysis, and (b) antigen-driv ...19853161746
thiouracil and antibody titers of chickens from lines divergently selected for antibody response to sheep erythrocytes.chickens from lines selected for high (ha) and low (la) antibody response to sheep red blood cells (srbc) were fed ad libitum either a diet containing 0 (control) or .1% thiouracil (tf) throughout two trials. chicks were injected intravenously with .1 ml of .25% srbc at 37 days of age in trial 1, and a booster of the same dosage was given to half of these chicks at 61 days of age. antibody titers were measured 5 and 3 days after primary and secondary inoculations. in trial 2, primary inoculation ...19883169356
nitrogen metabolism by lactating ewes and their lambs.twenty multiparous ewes and their newborn lambs were assigned to a 2 x 2 factorial experiment in which ewes were fed ad libitum either a moderate (mp, 15%) or a low (lp, 10%) cp diet and nursed either twin (t) or single (s) lambs. nitrogen (n) balance trials were conducted on both the ewes and lambs during wk 2, 4 and 8 of lactation. nitrogen balance, n digested and the portion of digested n retained were greater (p less than .01) with the mp diet. nitrogen retention and serum urea-n values were ...19883068224
regulation of immunoglobulin production after human marrow grafting. the role of helper and suppressor t cells in acute graft-versus-host disease.the effect of acute graft-versus host disease (gvhd) on t4 and t8 lymphocyte regulation of in vitro immunoglobulin production was explored. the peripheral blood lymphocytes from 20 patients were studied sequentially in the first 100 days after sibling bone marrow grafting for hematologic malignancy or aplastic anemia. t and non-t lymphocytes were prepared from peripheral blood by ficoll-hypaque density gradient centrifugation and sheep erythrocyte rosetting. t cells were enriched for t4 or t8 ce ...19862937188
thyroid hormone effects on neonatal thermogenesis.it is clear that thyroid hormones modulate non-shivering heat production of the newborn mammal. while some obvious thyroid hormone effects on thermogenesis can be demonstrated in adult, cold-acclimated or hibernating animals, these findings cannot be directly applied to the newborn, in which changes in amount and composition of brown adipose tissue, as well as sympathetic and thyroid system maturational events, are occurring. thyroid hormones do influence the prenatal development and subsequent ...19883293226
thyroid hormone kinetics during late pregnancy in the ovine fetus.the factors responsible for the changes in the plasma concentrations of thyroid hormones in the ovine fetus in late pregnancy were investigated by making serial measurements of the concentrations, metabolic clearance rates and production rates of t3 and t4 in 17 fetuses. the concentrations of t3 in fetuses of 135-145 days gestational age were four times higher than in those of 110-125 days but the concentrations of t4 were unchanged. the metabolic clearance rate of t3 halved over this period whe ...19883221061
susceptibility of rocky mountain bighorn sheep and domestic sheep to pneumonia induced by bighorn and domestic livestock strains of pasteurella haemolytica.bighorn sheep were inoculated intratracheally with suspensions of nonhemolytic pasteurella haemolytica biotype t (10(12) organisms) unique to wild bighorns, with beta-hemolytic p. haemolytica biotype t (10(12) organisms) isolated from clinically normal domestic sheep or intradermally with half a dose of a cattle vaccine containing p. haemolytica biotype a (10(5) organisms). the bighorn strain caused lobar necrotizing bronchopneumonia whereas both domestic livestock strains precipitated fatal sep ...19883196974
hyperiodothyroninaemia of neonates, its significance for thermogenesis.danowski et al. (1951) were probably the first who showed an increase of pbi in infants shortly after birth. later a number of investigators presented further evidence on the increased thyroid gland function in newborns. this condition named "neonatal thyroid hyperactivity" [fisher and oddie, 1964] was described also in animals. the available data indicate that all the newborn mammals till now studied, independently of the maturation stage of development they reach at birth, display some feature ...19883257052
immunological reactivity in children with wilms' tumor.cellular immune reactivity was investigated in 49 newly diagnosed children with wilms' tumor and compared to age-matched control. the level of total t (t4 degrees) and b lymphocytes was normal while the relative number of t lymphocytes with high affinity receptors for sheep erythrocytes (t29 degrees) was significantly decreased in the patients studied. the lymphocyte response to pha in vitro was diminished but pha-induced lymphokine production was not altered. the depression of t29 degrees level ...19863020456
partial primary structure of the t4 antigens of mouse and sheep: assignment of intrachain disulfide bonds.the t4 antigens of mouse and sheep have been purified to homogeneity and partially sequenced using protein and peptide microsequencing techniques. both mouse and sheep antigens bear distinct homology to human t4, having an amino-terminal segment that is homologous to the k-chain variable region (vk). a surprisingly high degree of sequence divergence was nevertheless evident between the t4 antigens of the three mammalian species, suggesting an unusually rapid rate of evolution that is possibly re ...19863086886
in vivo depression of lymphocyte traffic in sheep by vip and hiv (aids)-related peptides.core pentapeptides and an octapeptide (peptide t) computer deduced from amino acid sequences from vasoactive intestinal peptide (vip) and the 120 gp external envelope of the hiv (aids) virus and synthesized have been reported to have important in vitro and in vivo activity including inhibition of hiv binding to cd4 surface antigens of brain cells and lymphocytes and limitation of hiv infectivity. two of these core pentapeptides, peptide ttnyt (peptide t [4-8]) and peptide tdnyt (vip [7-11]), are ...19883267011
t lymphocyte subset alterations following bluetongue virus infection in sheep and cattle.to determine potential mechanisms of differential disease expression in ruminants infected with bluetongue virus (btv), clinically normal, btv-seronegative, yearling sheep and cattle were infected subcutaneously with a standardized insect-source inoculum of btv serotype 17 (btv-17) (three infected and one contact control each) or animal adapted btv serotype 10 (btv-10) (three sheep only). btv was isolated from peripheral blood cell components of infected sheep and cattle and all infected animals ...19902156375
preferential saturation of brain 3,5,3'-triiodothyronine receptor during development in fetal lambs.the concentrations of t4 and t3 were measured in brain, liver, and lung of fetal lambs at 100 days gestational age. the highest concentrations of t4 were found in lung (26.8 ng/g). brain t4 (8.8 ng/g) was only 30% of lung t4. in contrast, higher concentrations of t3 were found in brain (1.8 ng/g) than in lung (0.39 ng/g) or liver (0.36 ng/g). nuclear t3 was 16% of the total t3 in brain and 44% of that in lung. the degree of saturation of the nuclear t3 receptor was estimated from the concentrati ...19883338407
dietary calcium and metacarpal growth in ewes.the effects of excess dietary calcium on bone growth were quantified in 44 ewes fed ad libitum diets that contained one of four levels of dietary calcium (0.37, 0.56, 1.13 and 1.80%) and 0.42% phosphorus. animals were slaughtered at one of six ages, circulating concentrations of hormones and minerals were measured and bone morphometry was evaluated. none of the diets impaired normal bone growth of the metacarpal as evaluated by overall length, cortical index and growth plate width. circulating p ...19883404288
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