Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| [regulations of igm immune response. iv. effect of the hapten: carrier ratio and the nature of the carrier on the intrinsic and functional affinity of carp dnp-antibodies]. | carp anti-dnp antibodies were raised by various dnp-carrier conjugates. their intrinsic affinity (k0) to monovalent e-dnp-l-lysine and functional affinity (df) for binding to the multivalent dnp-t4 bacteriophages were determined. the functional affinity of antibodies elicited by t-cell-dependent dmpn-hsa (n = 3, 15, 33) is relatively high (kf):1010-1012 m-1). these kf values increase more than k0 during the immune response. the functional affinity is dependent on the molar knp: hsa ratio. the me ... | 1979 | 121787 |
| studies on the regulation of igm immune response. vii. changes in the affinity of antibodies and cell receptors after immunization with the t-cell independent antigen dnp-ficoll. | a/j-mice immunized by a single injection with dnp21-ficoll respond on the humoral level exclusively with igm antibodies. the intrinsic association constants (k0) of igm anti-dnp to monovalent hapten e-dnp-l-lysine are within the range of 105-106 m-1 and do not change significantly during the immune response. on the other hand, the functional association constants (kf) of pentameric igm to multivalent dnp-t4 bacteriophage increase from 1010 m-1 at 3rd day up to 1012 m-1 at 8th day. subsequently, ... | 1979 | 121788 |
| characteristics of thyroid function in experimental protein malnutrition. | two experiments were conducted to study the effects of protein malnutrition on thyroid function. resting oxygen consumption and serum concentrations of triiodothyronine (t3), thyroxine (t4) and thyroid stimulating hormone (tsh) were measured and correlated with thyroid histology, gain in weight, feed efficiency and carcass energy content in male rats fed isoenergetic diets ad libitum containing 22% (control) or 8% (protein malnourished, pm) casein for 28 or 32 days postweaning. a third group was ... | 1979 | 109585 |
| thyrotropin-releasing hormone and thyroid hormones in amniotic fluid. | immunoassayable trh (itrh) was measured in 50 amniotic fluid specimens with a mean concentration of 207 +/- 26 (se) pg/ml. this itrh demonstrates parallelism with the standard curve for synthetic trh. with increasing gestational age there is an increase in itrh levels in amniotic fluid with a decrease in 3,3',5'-triiodothyronine levels (rt3), while thyroxine levels (t4) remain unaltered. preliminary data suggest that itrh levels in amniotic fluid that are less than 150 pg/ml after 32 weeks of ge ... | 1979 | 110151 |
| thyroid axis in patients with cushing's syndrome. | thyroid hormone values and serum thyrotropin (thyroid-stimulating hormone [tsh]) responses to the intravenous administration of 400 micrograms of protirelin were determined in ten patients with cushing's syndrome and in ten matched normal subjects. in patients with cushing's syndrome, the serum thyroxine (t4) level was mildly depressed and free t4 level was normal. the mean (+/- sd) concentrations of serum triiodothyronine (t3) and free t3 were both reduced in patients compared with normal subje ... | 1979 | 110278 |
| replication of the linear mitochondrial dna of tetrahymena pyriformis. | 1. electron micrographs of the linear mtdna from tetrahymena pyriformis strain gl show linear molecules with a duplex 'eye' of variable size in the middle. this indicates that replication of this dna starts near the middle of the molecule and proceeds bidirectionally to the ends, as previously shown for the mtdna of strain st (arnberg, a.c., van bruggen, e.f.j., clegg, r.a., upholt, w.b. and borst, p. (1974) biochim. biophys. acta 361, 266-276). the mtdnas of these two strains have little base s ... | 1979 | 110348 |
| the t3/tbg ratio and the biochemical investigation of thyrotoxicosis. | the relationship between serum tri-iodothyronine (t3) and thyroxine-binding globulin (tbg) has been studied in euthyroid subjects. this relationship is similar to that previously described for thyroxine (t4) and tbg. serum t3, tbg and t4 data are presented for euthyroid subjects of all ages and the t4:t3 and t3:tbg ratios calculated. similar data has been derived for patients with clinically proven thyrotoxicosis and for patients in which the diagnosis was in doubt. the results suggest the t3:tb ... | 1979 | 110492 |
| inherited abnormal thyroid hormone-binding protein causing selective increase of total serum thyroxine. | a 9-yr-old boy is described in whom increased serum t4 concentration, increased t3 uptake, and increased free t4 index were associated with a euthyroid clinical state with normal total serum t3. t4-binding globulin (tbg), measured by ria, was decreased. reverse flow paper electrophoresis of serum proteins after reaction with radioactively labeled t4 demonstrated increased binding of t4 to a protein with electrophoretic mobility corresponding to albumin. displacement of serum protein-bo-nd [125i] ... | 1979 | 110823 |
| effects of methylmercaptoimidazole (mmi), propylthiouracil (ptu), potassium perchlorate (kclo4) and potassium iodide (ki) on the serum concentrations of thyrotrophin (tsh) and thyroid hormones in the rat. | male sprague-dawley rats were given graded doses of methylmercaptoimidazole (mmi), propylthiouracil (ptu), kclo4 or ki in drinking water for 4 days, or the lowest effective dose of each drug for various times. the rats were sacrificed at 1--2 p.m. and serum t3, t4 and tsh concentrations were measured by radioimmunoassays. it was found that administration of 5 mg/l of mmi, 10 mg/l of ptu and 100 mg/l of kclo4 for 4--14 days induced a transient rise in serum tsh and a fall in serum t3 or t4 or in ... | 1979 | 111448 |
| thyroid hormones and tsh, prolactin and lh responses to repeated trh and lrh injections in depressed patients. | twelve patients with unipolar depressive disorders received 600 microgram of synthetic trh or lrh, in a random order, for 3 days each. placebo injections were given as two 3-day courses prior to and between the active treatments. serum tsh, prolactin (prl) and lh were measured by radioimmunoassays prior to the experiment as well as immediately before and 20 min after each injection. serum t4 and t3 were determined by radioimmunoassays before the treatments and 24 h after the first two trh inject ... | 1979 | 111472 |
| long-term perspectives of thyroxine administration in neonatal rats. | newborn pups were injected with normal saline (group a) and exogenous thyroxine (group b). elevated t4 and decreased tsh levels from day 7 in group b continued until day 35. t4 and tsh were in normal range by day 42 and were similar to group a. weight gain was significantly lower in group b. on day 45, half hourly injections (subcutaneous) of trh were given to half of group a and group b each. remaining halves were injected with saline. tsh response to trh was significantly decreased in group b ... | 1979 | 112019 |
| normalized thyroxine as a screening test for hypothyroidism in full-term and preterm newborn babies. | thyroid function was assessed in full-term and preterm newborn babies by serum thyroxine (t4), normalized thyroxine (t4n) and thyroid-stimulating hormone (tsh) assays. at age 24 h, there was a significant difference in t4 and tsh values between the full-term and preterm groups; no such difference was found in the t4n values. by 21 days of age, the tsh values were still significantly higher in full-term babies compared with preterm ones, but the t4 values were similar. the t4, t4n and tsh values ... | 1979 | 112084 |
| dna-directed in vitro synthesis of beta-galactosidase. purification and characterization of stimulatory factors in an ascites extract. | previous studies have described a partially defined system for the dna-directed in vitro synthesis of beta-galactosidase (kung, h.f., redfield, b., treadwell, b.v., eskin, b., spears, c., and weissbach, h. (1977) j. biol. chem. 252, 6889-6894). an ehrlich ascites extract was shown in these in vitro studies to acylate escherichia coli trna with 13 amino acids, and the ascites extract was used in place of the corresponding 13 e. coli aminoacyl-trna synthetases. the present studies indicate that th ... | 1979 | 112101 |
| amenorrhoea, body weight and serum hormone concentrations, with particular reference to prolactin and thyroid hormones in anorexia nervosa. | twenty women with anorexia nervosa were investigated at varying stages during weight gain. basal prolactin and tsh and prolactin responses to trh were normal and unrelated to body weight. lh, fsh and 17 beta oestradiol were low in emaciated patients and rose with weight gain. there was no correlation between serum gonadotrophin and prolactin concentrations. t3 and t4 concentrations were low but t3 rose with weight gain during refeeding over 4-6 weeks, whereas t4 remained low. a positive correlat ... | 1979 | 112613 |
| thyroid function in chronic liver disease. | there is a recent hypothesis that thyroxine (t4), secreted by the thyroid gland under physiological conditions, is mono-deiodinated in extrathyroidal sites to form the more active 3, 3', 5-tri-iodothyronine (t3) before exerting biological activity at target tissue level. futhermore, circumstantial evidence suggests that the liver is an important site for the extra-thyroidal conversion of t4 to t3. thyoid hormone pathophysiology in liver disease is therefore of interest. patients with hepatic cir ... | 1979 | 112792 |
| thyroid status in fifty patients with alcoholic cirrhosis. | because the liver is of considerable importance in metabolism of thyroid hormones, plasma levels of thyroxine (t4), triiodotyronine (t3) with their unbound fractions (ft4 and ft3), reverse t3 (rt3)--an inactive isomer of t3-tyrotropin (tsh) and tsh response to thyrotropin releasing hormone (trh; 250 micrograms i.v.) were determined by radioimmunoassays in 50 clinically euthyroid patients with alcoholic cirrhosis. t4 mean concentration (7.3 micrograms/dl) did not differ from normal values but t3 ... | 1979 | 112793 |
| behavioral and endocrine responses of schizophrenic patients to trh (protirelin). | we studied the effects of intravenous protirelin (thyrotropin-releasing hormone) in 17 schizophrenic patients and 17 normal subjects. a total of 12 patients received protirelin, 0.5 mg, and, on another occasion, niacin, 2 mg, in a double-blind, crossover design. both behavioral and endocrine data were collected. five patients received protirelin in an open trial; only endocrine data were collected. protirelin caused about a 50% prompt decrease in psychotic symptoms. patients then tended slowly t ... | 1979 | 112944 |
| prospective randomized trial of combined oncological therapy for gastric carcinoma. | one hundred forty-two patients with all stages of gastric carcinoma were prospectively stratified into two divisions according to t.n.m. stage following, but irrespective of the type of surgical procedure. division i (t1-3, n1-2, m0) was randomized into a control group, and a treatment group who received 2000 rad in 8 fractions over 10 days with intravenous 5 fluorouracil (5 f.u.) at a dose of 500 mg daily x 4 days preirradiation and then 12.5 mg/kg daily for 5 days every 28 days for six courses ... | 1979 | 113074 |
| augmentation of pituitary thyrotrophin response to thyrotrophin releasing hormone during subphysiological tri-iodothyroinine therapy in hypothyroidism. | five hypothyroid patients are reported with increased pituitary tsh response to trh during administration of t3. in one patient treated with intravenous t3, 50 micrograms daily for 10 days, the peak serum tsh and total pituitary tsh reserve after trh increased coincident with increases in serum t3 and t4 levels and a decrease in the basal tsh concentration. in four patients treated with oral t3, the peak serum tsh and total pituitary tsh reserve after trh increased during administration of subph ... | 1979 | 113139 |
| pituitary and peripheral resistance to thyroid hormone. | a 32-year-old caucasian male, clinically euthyroid, with paranoid schizophrenia and granulocytopenia, had elevated total and free serum t4 and t3; serum tsh was normal (2.7 +/- 0.7 micronu/ml). there was no goitre present, no evidence of graves' disease, and no evidence of pituitary tumour. he had a normal response to methyl-trh, with a tsh increment of 14.6 micronu/ml, t3 increment of 212 ng/dl, and t4 increment of 4.7 microgram/dl; baseline value and decreased the tsh increment in response to ... | 1979 | 113140 |
| longitudinal study or serum thyroid hormones, chorionic gonadotrophin and thyrotrophin during and after normal pregnancy. | measurements of serum levels of thyroxine (t4), free t4, 3,5,3'-triiodothyronine (t3), free t3, 3,3',5'-triiodothyronine (reverse t3, rt3), thyroxine-binding globulin capacity (tbgcap), chorionic gonadotrophin (hcg) and thyrotrophin (tsh) were carried out prospectively in eight women with uncomplicated pregnancies, in order to examine interrelationships between the thyroid gland and thyroid stimulating hormones during pregnancy. during pregnancy the levels of t4, free t4, t3, rt3 and tbgcap were ... | 1979 | 113141 |
| pituitary-thyroid function of fetuses of hypothyroid and growth hormone treated hypothyroid rats. | maternal hypothyroidism induced by surgical thyroidectomy (tx) of the rat resulted in significantly higher fetal serum levels of thyroid stimulating hormone (tsh) and thyroxine (t4) on day 22 of gestation. surprisingly, administration of growth hormone (gh) to hypothyroid mothers increased further the fetal serum t4 and tsh. the in vitro uptake of 131i-t4 by erythrocytes was elevated significantly when incubated with serum from fetuses of both hypothyroid and hypothyroid gh-treated mothers. alth ... | 1979 | 113329 |
| [the circadian rhythm of the pituitary-thyroid regulatory cycle. serum thyrotropin (tsh), thyroxine (t4), triiodothyronine (t3), reverse triiodothyronine (rt3), and the thyroxine binding capacity (t3 test) in men in a diurnal profile]. | 1979 | 113642 | |
| different specific activities of the monomeric and oligomeric forms of plasmid dna in transformation of b. subtilis and e. coli. | (1) the low residual transforming activity in preparations of monomeric, supercoiled, circular (ccc) forms of the plasmids pc194 and phv14 could be attributed to the presence in such isolates of a small number of contaminating multimeric molecules. (2) e. coli derived preparations of phv14, as in vitro recombinant plasmid capable of replication in both e. coli and b. subtilis, contain oligomeric forms of plasmid dna in addition to the prevalent monomeric ccc form. the specific transforming activ ... | 1979 | 113646 |
| t4, t3 and reverse-t3 determinations in connection with the trh test in the evaluation of possible hyperthyroidism. | one disadvantage of the trh test is that an absent or blunted tsh response is seen not only in hyperthyroid patients but also in some normal subjects. the aim of the present study was to elucidate whether the discriminatory power between eu- and hyperthyroidism could be increased by determining the t3 and t4 levels before and after the trh administration. the study population consists of 30 patients referred for evaluation of suspected hyperthyroidism. the results show that all but one of the pa ... | 1979 | 113985 |
| [trh response in 53 patients with chronic alcoholism (author's transl)]. | a study of thyroid function was undertaken in 53 patients with chronic alcoholism the following tests were performed: t3 ria, t4 ria, t3 test and i.v. trh-test. the patients were divided into 3 groups according to the degree of liver injury: histologically documented fibrosteatosis (group 1), cirrhosis (group 2); group 3 consisted of severe cirrhosis with coagulation defects precluding liver biopsy. 32 healthy subjects served as controls. free thyroxine index was normal in the 3 groups of patien ... | 1979 | 114079 |
| [sexual differences in the development of plasma thyroxine levels in the embryo and young chick]. | plasma thyroxine (t4) levels were separately ascertained in male and female embryo and young chicken from the 12th day of incubation till the 4th day after hatching by the thyroxine binding globulin technique. in both sexes, plasma t4 reach a peak the 20th day of incubation, but values are significantly higher in females. a sharp decrease occurred thereafter, plasma t4 tending toward adult values the 4th day after hatching. | 1979 | 114325 |
| a method for construction of specialized transducing phage rho 11 of bacillus subtilis. | dna from a temperate phage rho 11 and chromosomal dna of bacillus subtilis 168 were digested with endonuclease ecori and then ligated with t4 polynucleotide ligase. the ligated dna fragments were used to transform a lysogenic strain, b. subtilis spoa12 lys21 hisa1 leua8 p11, and lys+, his+ or leu+ transformants were selected. the cells of each type were then mixed, grown and treated with mitomycin c; the induced phages were tested for abilities abilities to form plaques and to tranduce the auxot ... | 1979 | 109355 |
| guidelines: filter paper t4 and tsh screening tests. | 1979 | 162706 | |
| the role of energy-yielding atpase and respiratory chain at early stages of bacteriophage t4 infection. | 1979 | 155013 | |
| [studies on the control of igm-antibody synthesis v. affinity of anti-dnp antibodies in carps immunized with dnp-ficoll (author's transl)]. | the dynamics of affinity of anti-dnp antibodies of carps immunized with t cell independent dnp-ficoll was studied during the immune response. the intrinsic affinity (ko) of antibodies to monovalent epsilon-dnp-lysine is 10(5)--10(6)m-1 and does not change significantly in course of the immunisation. the affinity of tetrameric igm antibodies to multivalent dnp-t4 conjugate is only 10(2)--10(3)-fold greater than to monovalent hapten, contrary to about 10(6)-fold higher values following immunisatio ... | 1979 | 157685 |
| role of polymeric forms of the bacteriophage phi x174 coded gene a protein in phi xrfi dna cleavage. | gene a of the phi x174 genome codes for two proteins, a and a* (linney, e.a., and hayashi, m.n. (1973) nature new biol. 245, 6-8) of molecular weights 60,000 and 35,000, respectively. the phi x a* protein is formed from a natural internal initiator site within the a gene cistron while the phi x a protein is the product of the entire a gene. these two proteins have been purified to homogeneity as judged by sodium dodecyl sulfate polyacrylamide gel electrophoresis. previous studies have shown that ... | 1979 | 158588 |
| mutants of escherichia coli that do not contain 1,4-diaminobutane (putrescine) or spermidine. | strains of escherichia coli k12 have been constructed which do not contain any of the polyamines normally present in a wild type strain, namely, 1,4-diaminobutane (putrescine) and spermidine. this phenotype arises as a consequence of the assembly into these strains of deletion mutations in spea (arginine decarboxylase), speb (agmatine ureohydrolase), spec (ornithine decarboxylase), and sped (adenosylmethionine decarboxylase). the polyamine-deficient strains grow indefinitely in the absence of po ... | 1979 | 159306 |
| relation between bacteriophage t4 dna replication and late transcription in vitro and in vivo. | 1979 | 160129 | |
| molecular cloning of the dna ligase gene from bacteriophage t4. i. characterisation of the recombinants. | 1979 | 160464 | |
| l-thyroxine effects upon atpase activities of several subcellular fractions of liver of the rat and the guinea pig. | the effect of thyroxine administration upon atpase activity of several subcellular fractions of livers from rats and guinea pigs has been studied. to determine a patho-physiological dose of levo thyroxine [t4] for guinea pigs, a dose-response curve was examined of t4 effect upon oxidative phosphorylatin of guinea pig liver mitochondria. maximum stimulation of mitochondrial respiration without uncoupling of oxidative phosphorylation was found with 15 microgram of t4 per 100 g body weight per day. ... | 1979 | 160923 |
| site-specific mutagenesis using synthetic oligodeoxyribonucleotide primers: ii. in vitro selection of mutant dna. | a method for the in vitro selection of mutant dna has been devised as an adjunct to the recently developed method for the use of short enzymatically-synthesized oligodeoxyribonucleotides of defined sequence as site-specific mutagens for circular dna. the selection method uses the mutating oligodeoxyribonucleotide as a primer for escherichia coli dna polymerase i (large fragment) under conditions where there is preferential interaction with mutant dna template. after ligation using t4 dna ligase, ... | 1979 | 161246 |
| a dna-unwinding enzyme induced in bacteriophage-t4-infected escherichia coli cells. | a single-stranded dna-dependent atp gamma-phosphohydrolase of mr 56000 induced after infection of escherichia coli cells with bacteriophage t4, probably the atpase dependent on gene dda of the phage, was isolated. studies on the enzyme show that in the presence of atp and m2+ ions it is capable of dissociating partially double-stranded fd bacteriophage dna into the single strands and that some 3000 enzyme copies are required to unwind the 6400-nucleotides-long dna. unwinding is inhibited by redu ... | 1979 | 218815 |
| the purification of nuclease-free t4-rna ligase. | rna ligase has been highly purified in good yields from bacteriophage t4-infected escherichia coli by a rapid and reproducible procedure. the enzyme is free of phosphomonoesterase and ribonuclease activities and is therefore suitable for the synthesis of oligoribonucleotides and for the labeling of the 3'-terminus of rna. greater than 90% of the protein in the enzyme preparation migrates as a single band on gradient polyacrylamide gels containing sodium dodecyl sulfate during electrophoresis. fo ... | 1979 | 219895 |
| subcellular localization of thyroxine and reverse triiodothyronine outer ring monodeiodinating activities. | in order to examine the subcellular localization of outer ring t4- and rt3-monodeiodinating activities, nuclear, mitochondrial, microsomal, cytosol, and plasma membrane fractions of rat liver homogenate were incubated with either t4 or rt3 in phosphate buffer (ph 7.35) in the presence of 2 mm dithiothreitol for 15 min at 37 c, and the amount of product (t3 in the case of t4 and 3,3'-diiodothyronine in the case of rt3) was measured by specific ria. the various tissue fractions were also examined ... | 1979 | 221175 |
| effects of hypophysectomy, thyroidectomy, and thyroxine on specific prolactin receptor sites in kidneys and adrenals of male rats. | the effect of t4 on specific prl binding in the kidneys and adrenals was measured in intact, hypophysectomized, and thyroidectomized male rats. prl binding in the kidneys was reduced from 12.1 +/- 1.1% in the intact group to 4.5 +/- 0.5% after hypophysectomy; 4-day replacement with t4 returned prl binding to intact values. t4 administered to intact rats significantly increased prl binding above intact values. thyroidectomy reduced prl binding in the kidneys from 14.9 +/- 1.2% to 7.0 +/- 0.6%, an ... | 1979 | 221176 |
| dna binding properties of the t4 dna helix-destabilizing protein. a calorimetric study. | 1979 | 221498 | |
| t4 gene 32 protein trypsin-generated fragments. fluorescence measurement of dna-binding parameters. | the intrinsic fluorescence of the t4 helix-destabilizing protein specified by gene 32 (32p) is not altered by the proteolytic removal of either the 6200-dalton cooh-terminal "a" region (32p*-a) or both the a and the 2300-dalton nh2-terminal "b" region (32p*-(a + b)). the intrinsic fluorescence of 32p, 32p*-a, and 32p*-(a + b) is decreased 23% by the addition of d(pt)8 and 34% by the addition of poly(dt). saturation binding curves of the percentage of change in protein fluorescence as a function ... | 1979 | 221499 |
| relationship of receptor affinity to the modulation of thyroid hormone nuclear receptor levels and growth hormone synthesis by l-triiodothyronine and iodothyronine analogues in cultured gh1 cells. | we have previously demonstrated that l-triiodothyronine (l-t3) induces an increase in growth hormone synthesis and messenger rna in cultured gh1 cells, a rat pituitary cell line. in addition to regulating the growth hormone response, l-t3 elicits a time- and dose-dependent reduction in the level of its nuclear receptor, which is a direct function of the occupancy of the receptor binding site. in this study we have compared the relative affinity of l-t3, triiodothyroacetic acid, d-triiodothyronin ... | 1979 | 221536 |
| endocrine response after burn. | the use of radioimmunoassays has made new advances in post-burn endocrine studies possible. the mean fasting iri plasma (pl.) levels were elevated for 7 weeks, sometimes reaching very high values. during ogtt, an impaired glucose tolerance and insulin resistance could be found. pl. hgh levels were normal or slightly increased, and their hypoglycemia-caused rise in the first two postburn weeks was blocked. renin and angiotensin ii pl. levels were high or very high in almost all burned patients. t ... | 1979 | 221969 |
| removal of t4 endonuclease v-sensitive sites from sv40 dna after exposure to ultraviolet light. | the induction and removal of sites sensitive to t4 endonuclease v from ultraviolet-irradiated simian virus 40 (sv40) form i (supercoiled) dna during a lytic infection of monkey cv-1 cells was investigated by agarose tube gel electrophoresis. endonuclease-sensitive sites were induced at a rate of 0.049 sites/sv40 genome per j/m2, or 1.4 sites/1 . 10(8) daltons of dna per j/m2. this value is similar to the yield of endonuclease-sensitive sites and pyrimidine dimers in uninfected host cv-1 cell dna ... | 1979 | 222324 |
| effects of thyrotoxicosis on mitochondrial enzymes of rat soleus. | cytochrome oxidase, glycerol-3-phosphate dehydrogenase, and succinate dehydrogenase were measured in mitochondrial fractions obtained from rat soleus muscle of control and 8 week t3 + t4 treated animals. under these conditions of prolonged treatment, there is a five-fold increase in the specific activities of both cytochrome oxidase and glycerole-3-phosphate dehydrogenase. significant increases in total cellular mitochondrial content and enzyme activities were observed in t3 + t4 treated animals ... | 1979 | 222661 |
| neisseria gonorrhoeae membrane microenvironment studied by spin-label electron spin resonance: comparison of colony types. | spin-label electron spin resonance was used to characterize the microenvironment around spin probes which localize (i) in membranes, (ii) at the membrane surface, or (iii) in the cytoplasm of living neisseria gonorrhoeae. four colony types (t1, t2, t3, and t4) of gonococci were compared on the basis of the electron spin resonance parameters 2t parallel to, s (order parameter), and tau c (microviscosity). the concentration of spin label used had little or no effect on viability. t1 and t2 gonococ ... | 1979 | 222734 |
| receptor affinity and biological potency of thyroid hormones in thyrotropic cells. | the nuclear receptor affinity for l-triiodothyronine (l-t3), l-thyroxine (l-t4), l-triiodothyroacetic acid (triac), and d-triiodothyronine (d-t3) was compared to the potency of these thyroid hormone analogues in regulating thyrotropin (tsh) production and the number of membrane receptors for thyrotropin-releasing hormone (trh) in mouse thyrotropic tumor cells in culture. l-t3 and triac were equally potent and d-t3 was one-sixth to one-fifth as potent in binding to the receptor and in regulating ... | 1979 | 223453 |
| biphasic inhibitory and stimulatory effects of thyrotropin on the mitotic activity of thyroid explants cultured in vitro. | an influence of thyrotropin (tsh), dibutyryl cyclic amp (dbcamp), triiodothyronine (t3) and thyroxine (t4) on the mitotic incidence in the organ-cultured rat thyroid was studied. the study has revealed biphasic inhibitory and stimulatory effects of tsh on the thyroid mitotic activity. the inhibitory effect occurred 14 h after an exposure of the thyroid explants to tsh and was enhanced by t3. a similar inhibitory effect was observed after an exposure of the explants to dbcamp. 24 h after the expo ... | 1979 | 223838 |
| probing dna replication mechanisms with the t4 bacteriophage in vitro system. | 1979 | 225114 | |
| cyclic 3',5'-adenosine monophosphate (camp) in a 42-month-old child with clinical evidence of multiple hormonal disturbances. | in a boy aged 42 months, small stature, retarded psychomotor development, dry skin, excessive thirst, polyuria, cryptorchidism, and rickets were signs of multihormonal disturbances. contrary to the clinical manifestations, laboratory investigations showed normal or raised levels of hormones (hgh, insulin, t3ru, t4, tsh, pth). the camp level in the plasma was low and its urinary excretion was reduced. after administration of hgh, adrenaline, t3, t4, pitressin, vitamin d3 and aminophylline there w ... | 1979 | 225175 |
| the effects of growth hormone, thyroxine and insulin on the activities of reduced nicotinamide adenine dinucleotide phosphate dehydrogenase, glucose-6-phosphatase and glycogen phosphorylase in fetal rat liver. | growth hormone (gh), thyroxine (t4) and insulin were injected, in utero into 20.5 day-old rat fetuses to study the effects of these hormones on the activities of liver nadph dehydrogenase, glucose-6-phosphatase and glycogen phosphorylase. it was found that at 21.5 days of gestation, gh increases the fetal liver glucose-6-phosphatase activity and decreases the liver glycogen phosphorylase activity. t4 treatment augments the activity of nadph dehydrogenase even at 0.3% of the dose shown previously ... | 1979 | 225253 |
| size of infectious dna from human and murine cytomegaloviruses. | viral dna was isolated from human and murine cytomegalovirus by equilibrium centrifugation in cesium chloride gradients. the size of the dna was measured relative to t4 dna by velocity sedimentation in neutral glycerol gradients, and fractions were assayed for infectious dna. infectious murine cytomegalovirus dna sedimented as a single peak with an estimated molecular weight of 136 x 10(6). infectious human cytomegalovirus dna was detected in two peaks with molecular weights of 130 x 10(6) and 1 ... | 1979 | 225527 |
| involvement of eucaryotic deoxyribonucleic acid polymerases alpha and gamma in the replication of cellular and viral deoxyribonucleic acid. | in an effort to identify the deoxyribonucleic acid (dna) polymerase activities responsible for mammalian viral and cellular dna replication, the effect of dna synthesis inhibitors on isolated dna polymerases was compared with their effects on viral and cellular dna replication in vitro. dna polymerase alpha, simian virus 40 (sv40) dna replication in nuclear extracts, and cv-1 cell (the host for sv40) dna replication in isolated nuclei all responded to dna synthesis inhibitors in a quantitatively ... | 1979 | 226127 |
| plasma free tryptophan, brain serotonin, and an endocrine profile of the genetically obese hyperglycemic mouse at 4--5 months of age. | genetically obese hyperglycemic mice (ob/ob) were compared with their nonlittermate lean controls at 4-5 months of age with regard to brain serotonin, pituitary acth content, and circulating levels of glucose, glucagon, insulin, tsh, t3, t4, total tryptophan and free tryptophan. brain serotonin pituitary acth content, and plasma insulin, glucose, total tryptophan, and free tryptophan were all significantly higher in obese mice than in the controls. tsh, t3, and t4 were not significantly differen ... | 1979 | 226347 |
| [the characterization of nuclear triiodo-l-thyronine receptors of rabbit liver (author's transl)]. | the binding characteristics and physical properties of the nuclear receptors of rabbit liver were studied. the receptors were extracted with 0.4m kcl from purified hepatic nuclei and were incubated with increasing doses of 125i-triiodo-l-thyronine (l-t3) and stable l-t3 for 2 hours at 20 degrees c. scatchard analyses indicated that the association constant (ka) of the nuclear receptors was 1.5 x 10(10)m-1, and that maximal binding capacity was about 0.12 pmol t3 per 1 ml of nuclear extract, equi ... | 1979 | 226424 |
| early effects of thyroidectomy and triiodothyronine administration on rat-liver mitochondria. | this work was undertaken to study the action exerted by thyroid hormones on mitochondria. by day 6 after thyroidectomy, the respective activities of two inner-membrane enzymes--succinate and beta-hydroxybutyrate cytochrome c reductases--had already dropped by 32 and 50%, whereas, in the outer membrane, the activity of rotenone-insensitive nadh-cytochrome c reductase did not change significantly. the decrease in the activity of the inner-membrane enzymes closely followed the disappearance of t3 a ... | 1979 | 226438 |
| purification of the t4 gene 32 protein free from detectable deoxyribonuclease activities. | detailed procedures are presented which allow reproducible preparation of t4 gene 32 protein, a helix-destabilizing protein essential for dna replication and genetic recombination in t4 bacteriophage-infected escherichia coli cells. although 32 protein can be purified to better than 99% homogeneity by any one of several procedures, these methods have been developed to remove trace amounts of contaminating deoxyribonucleases, which are present in high levels in the original infected cells. two al ... | 1979 | 226522 |
| plasma high density lipoprotein cholesterol in thyroid disease. | the plasma levels of high density lipoprotein cholesterol (hdl-c) were reduced in 16 hyperthyroid female patients compared to 37 euthyroid women (33.5 +/- 8 vs. 51.5 +/- 13 mg/dl (mean +/- sd); p less than 0.001). when 5 patients were restudied after restoration of the euthyroid state, plasma hdl-c increased from 29 +/- 5 to 43 +/- 11.5 mg/dl (p less than 0.05). in addition, in 22 hypothyroid women, hdl-c levels were also diminished compared to the euthyroid group (43.4 +/- 15.5 vs. 51.5 +/- 13 ... | 1979 | 226559 |
| t4 dna topoisomerase: a new atp-dependent enzyme essential for initiation of t4 bacteriophage dna replication. | a novel atp-dependent dna topoisomerase which makes reversible double-strand breaks in the dna double helix has been purified to near homogeneity from t4 bacteriophage-infected escherichia coli cells. genetic data suggest that this activity is essential for initiating t4 dna replication forks in vivo. | 1979 | 226889 |
| synthesis and enzymatic properties of deoxyribooligonucleotides containing methyl and phenylphosphonate linkages. | chemical methods for the synthesis of short deoxyribooligonucleotides containing methyl and phenylphosphonodiester linkages have been developed. the interaction of two such nonionic dinucleotide analogs, t(pch3)t and t(pc6h5)t, with several enzymes has been investigated. because of the phosphonate linkage each dinucleotide exists as a diastereomeric pair as shown by thin layer chromatography and enzymatic studies. both isomers of each dinucleotide can be phosphorylated by t4-polynucleotide kinas ... | 1979 | 226943 |
| t4 dna-delay proteins, required for specific dna replication, form a complex that has atp-dependent dna topoisomerase activity. | under some conditions, t4 dna replication requires the products of the dna-delay genes, genes 39, 52, 58, and 60. by using an in vitro complementation assay that stimulates dna replication in t4 39(-)-infected cell extracts, t4 gene 39 protein has been purified. the purified fraction also contains complementing activities for t4 genes 52 and 60. on sodium dodecyl sulfate/polyacrylamide gel analysis the purified preparation exhibits three protein components: a 51,000-dalton protein corresponding ... | 1979 | 226976 |
| imparied cyclic-amp response to thyrotrophin in congenital hypothyroidism with thyroglobulin deficiency. | a 19 year old man had congenital hypothyroidism and severely retarded development. his thyroid gland was not enlarged and laboratory findings included low serum concentration of t4 (2.8 microgram/100 ml) and t3 (16 ng/100 ml) with a high level of tsh (52 microu/ml) that rose to 192 microu/ml after trh. 131i uptake by the thyroid was normal (41.5% at 24 h) and did not show a normal increase after exogenous tsh administration (49.5% at 24 h). the perchlorate discharge test was negative and no anti ... | 1979 | 227208 |
| a new gene of escherichia coli k-12 whose product participates in t4 bacteriophage late gene expression: interaction of lit with the t4-induced polynucleotide 5'-kinase 3'-phosphatase. | we isolated five escherichia coli mutants deficient in their ability to support the late (replication-coupled) gene expression of t4 bacteriophage at 30 degrees c. these mutants, which we call lit mutants, define at least one novel gene at 25 min on the e. coli map. they were selected in an attempt to obtain mutants which restrict the growth of t4 mutants deficient in polynucleotide 5'-kinase 3'-phosphatase but not that of wild-type t4 at 37 degrees c. some of the mutants do have these phenotype ... | 1979 | 227837 |
| escherichia coli mutants thermosensitive for deoxyribonucleic acid gyrase subunit a: effects on deoxyribonucleic acid replication, transcription, and bacteriophage growth. | temperature-sensitive nala mutants of escherichia coli have been used to investigate the structure and functions of deoxyribonucleic acid (dna) gyrase. extracts of one such mutant (nala43) had thermosensitive dna gyrase subunit a activity but normal gyrase subunit b activity, proving definitively that nala is the structural gene for subunit a. extracts of a second nala (ts) mutant (nala45) had a 50-fold deficiency of gyrase subunit a activity. the residual dna supertwisting was catalyzed by the ... | 1979 | 227840 |
| metabolism of okazaki fragments during simian virus 40 dna replication. | essentially all of the okazaki fragments on replicating simian virus 40 (sv40)dna could be grouped into one of three classes. class i okazaki fragments (about 20%) were separated from longer nascent dna chains by a single phosphodiester bond interruption (nick) and were quantitatively identified by treating purified replicating dna with escherichia coli dna ligase and then measuring the fraction of okazaki fragments joined to longer nascent dna chains. similarly, class ii okazaki fragments (abou ... | 1979 | 227871 |
| a new system for studying molecular mechanisms of mutation by carcinogens. | a new system for studying the molecular mechanisms of mutation by carcinogens is described. the system involves (a) site-specific modification of the essential gene g in phi x174 replicative form dna by a combination of chemical and enzymatic steps; (b) production of mutant virus carrying a change at a single preselected site by transfection of spheroplasts with the site modified phi x174 dna; (c) detection and propagation of mutants using a host carrying the plasmid, p phi xg, that rescues all ... | 1979 | 227905 |
| preferential in vitro assembly of nucleosome cores on some at-rich regions of sv40 dna. | we have found that nucleosomes reconstituted from histone octamers and sv40 dna form i by progressively decreasing the salt concentration from 2 m nacl are formed preferentially around 0.27, 0.37, 0.50 and 0.85 on sv40 dna (relative to the ecori site). when sv40 dna form iii is used, the nucleosomes form mainly at 0.28, 0.38, 0.61 and 0.83. these sites are very close to both the sites of rna chain initiation by calf thymus rna polymerase b on sv40 dna form i (0.25, 0.35, 0.42 and 0.88) and the r ... | 1979 | 228248 |
| effects of thyroid hormones on liver binding sites for human growth hormone, as studied in the rat. | several weeks after thyroidectomy (t), female rats stopped growing, and their pituitary gh content had decreased to less than 2--3% of the values found for age-matched controls (c). the liver membranes of such animals were explored with human gh (hgh). it was found that in the severely hypothyroid t rat, the number, but not the affinity, of the lactogenic binding sites was markedly reduced. treatment of these rats for 3 weeks with 1.75 micrograms or t4 or 0.5 micrograms t3/100 g body weight/day ... | 1979 | 228880 |
| [studies on the radioreceptor assay of tsh: the binding of 125i-tsh to the human thyroid receptor and the interaction of lats-igg (author's transl)]. | the radioreceptor assay system for tsh is considered to be useful in quantitating the hormone and analyzing the mechanism of its action. the assay was established, and the interaction of abnormal thyroid stimulators in graves' patients was evaluated in this assay system. a 10,000xg fraction of human thyroid homogenates was used as the receptor. human tsh supplied from nih was iodinated by using lactoperoxidase. the binding of 125i-tsh to the receptor was small, and 125i-tsh was further purified ... | 1979 | 228997 |
| [studies on the radioreceptor assay of tsh: the properties of tsh-binding inhibitor immunoglobulins (tbii) in patients with graves' disease (author's transl)]. | in the radioreceptor assay system for tsh, serum immunoglobulin g (igg) from some patients with graves' disease has been shown to inhibit the binding of labelled tsh to its receptor sites. in order to clarify the properties of these tsh-binding inhibitor immunoglobulins (tbii) in patients with graves' disease, tbii were measured in sera from 31 untreated and 51 131i-treated patients, and their relation to clinical and laboratory findings was studied. tbii were detected in 18 (60%) out of 31 pati ... | 1979 | 228998 |
| effects of surgical stress and corticotrophin on the peripheral metabolism of thyroid hormones in rabbits. | the effect of surgical stress and acth injection on the peripheral monodeiodination of thyroxine (t4) was studied in the rabbit. these stimuli resulted in a switch from the peripheral formation of tri-iodothyronine (t3) to reverse t3 in normal rabbits and in rabbits whose thyroidal secretion was suppressed by administration of t4. this is analogous to the situation in man. these changes were not due to alterations in the serum binding capacity for thyroid hormones. | 1979 | 229182 |
| determination of the length distribution of poly(a) at the 3' terminus of the virion rnas of emc virus, poliovirus, rhinovirus, rav-61 and cpmv and of mouse globin mrna. | rapid, detailed, and accurate analysis of the length spectrum of 3' terminal poly(a) in an rna population can be obtained by 3'-terminal 32p-labelling of rna with t4 rna ligase, digestion with ribonucleases t1 and a, and use of gel sequencing methods. length distributions of 3'-terminal poly(a) of emc virus, poliovirus, rhinovirus, rav-61, and cpmv virion rnas as well as mouse globin mrna are presented. | 1979 | 229465 |
| control of the hypothalamus-pituitary-adrenal axis in young and older rats injected with thyroxine. | administration of t4 on alternate weeks for 30 weeks at a dosage which does not alter body weight depresses basal serum corticosterone levels in older rats (575 days), but not in young animals (260 days). similar serum corticosterone response to hpa axis stimulation occurs regardless of age or t4 injection. | 1979 | 230073 |
| effects of thyroxine treatment on the hepatic plasma membrane atpase activity in rats. | the effects of t4 and t3 upon atpase activity of plasma membrane preparations produced by different methods has been studied. media without na+ or k+ was used to identify mg++ activated atpase, and media containing 100-120 mm na+ and 20-30 mm k+ in addition to mg++ was used to identify the augmented activity of na-k atpase. we also utilized media containing na+, k+, and mg++ in the presence and absence of ouabain to identify the na+-k+ activation. we found no effect of doses of thyroxine in the ... | 1979 | 231081 |
| relationship between plasma prolactin concentration and pituitary function in patients with a pituitary adenoma. | the influence of hyperprolactinaemia on endocrine functions in forty-two consecutive patients with untreated pituitary tumours was studied. patients with acromegaly, cushing's disease and nelson's syndrome were excluded. sixteen patients (eleven men and five women) had a pituitary adenoma with suprasellar extension and twenty-six (eleven men and fifteen women) had a small intrasellar tumour. basal plasma prolactin concentration was measured in all. thyroid function was assessed by plasma thyroxi ... | 1979 | 231491 |
| the bam h1 restriction site in the bacteriophage t4 chromosome is located in or near gene 8. | bacteriophage t4 cytosine-containing dna is cleaved at a single site by the restriction endonuclease, bam h1. the site lies within the late region of the t4 genome, close to, or within, gene 8, one of the structural genes of the phage particle baseplate. | 1979 | 231540 |
| electron microscopic mapping of rna transcribed from the late region of polyoma virus dna. | the polyoma virus (py) rna species transcribed from the l dna strand of the "late" region of the py genome in py-infected mouse cells have been mapped by hybridization with specific fragments of py dna followed by electron microscopic visualization of the hybrids. total cellular polyadenylated py-specific rna molecules having an s value in the range of 16s to 20s were purified by oligodeoxythymidylic acidcellulose column chromatography, preparative hybridization with py dna, and sucrose gradient ... | 1979 | 232179 |
| secondary structures in polyoma dna. | three reproducible secondary-structure features were observed on single strands of polyoma virus dna mounted for electron microscopy by the t4 gene 32 protein technique: (i) a hairpin fold-back extending from 92.9 +/- 0.8 to 95.0 +/- 0.7 map units; (ii) a small loop extending from 63.2 +/- 3.1 to 68.5 +/- 2.8 map units; and (iii) a big loop extending from 51.9 +/- 2.3 to 68.9 +/- 2.1 map units. both loops are bounded by inverted repeat stems of length 40 +/- 20 base pairs. the stem sequences aro ... | 1979 | 232183 |
| combined test of hypothalamic-pituitary function in growth-retarded children treated with growth hormone. ii. secretion of lh, fsh, tsh, prolactin and acth. | a total number of 23 patients treated with human growth hormone were retested by use of a combined pituitary stimulation test. plasma concentrations of gh, fsh, lh, tsh, t4, t3, prolactin (prl), acth and cortisol were measured before and after stimulation with hypoglycemia, trh and lhrh. the test was performed in patients with persistent gh deficiency (group a) and patients with transitory gh deficiency (group b). in group a a normal pubertal development was found in three patients, whereas in p ... | 1979 | 232353 |
| [thyroid hormone action at cellular level: role of tiroxine (t4) and triiodothyronine (t3) on the maintenance of thyroid status (author's transl)]. | 1979 | 233042 | |
| effect of acth-stimulated glucocorticoid hypersecretion on the serum concentrations of thyroxine-binding globulin, thyroxine, triiodothyronine, reverse triiodothyronine and on the tsh-response to trh. | the responses of serum concentrations of tsh, thyroxine (t4), triiodothyronine (t3) and of reverse triiodothyronine (rt3) to i. v. administration of 0.4 mg thr were examined prior to (and after) i. m. administration of acth (2 mg synacthen depot) in 7 euthyroid women using estrogen-containing oral contraceptives and in 8 controls, with the following results: (1) an increase in endogenous glucocorticoid secretion is associated with a depression of the tsh response to trh; (2) tsh formed in decrea ... | 1979 | 233400 |
| diffusion-controlled reactions on spherical surfaces. application to bacteriophage tail fiber attachment. | we have explored the kinetic implications of a model that may account for the acceleration of tail fiber (f) attachment to baseplates (b) by whiskers (w) on bacteriophage t4. the model assumes that a w-f complex is formed initially, and that the tethered fiber then undergoes rotational diffusion until a b-f encounter takes place. in the absence of whiskers, b-f complexes must form unassisted. formation of a w-f intermediate will accelerate f attachment to b if (a) the bimolecular rate constant f ... | 1979 | 262439 |
| a method for the enzymatic synthesis and purification of [alpha-32p] nucleoside triphosphates. | a simplified method is described for the enzymatic synthesis and purification of [alpha-32p]ribo- and deoxyribonucleoside triphosphates. the products are obtained at greater than 97% radiochemical purity with yields of 50--70% (relative to 32pi) by a two-step elution from deae-sephadex. all reactions are done in one vessel as there is no need for intermediate product purifications. this method is therefore suitable for the synthesis of these radioactive compounds on a relatively large scale. the ... | 1979 | 218171 |
| thyroxine and na+ transport in toad: role in transition from poikilo- to homeothermy. | the effects of thyroxine (t4) on na+ transport, oxygen consumption (qo2), and na+-k+-atpase activity were studied in the urinary bladder and liver of the toad bufo marinus. in the bladder, t4 in vitro (10(-8) to 10(-6) m) had no significant effect on these parameters during 15 h of incubation. when injected intraperitoneally (approximately 20 microgram/(kg body wt.day) for 6 days), t4 lowered base-line, short-circuit current by 62% (p less than 0.0025) and potential difference by 37% (p less tha ... | 1979 | 218460 |
| time course of the t3- and t4-induced increase in rat soleus muscle mitochondria. | citrate synthase and cytochrome c increase in soleus muscle of rats in response to excess thyroid hormones. the half times of the increase in the levels of citrate synthase and cytochrome c in soleus muscle during induction are greater than the half times of the decline in enzyme levels after cessation of treatment (15 days vs. 7 days for citrate synthase). denervation of the soleus does not prevent the increase in citrate synthase in response to thyrotoxicosis. this provides evidence that thyro ... | 1979 | 218461 |
| temperature-sensitive mutation in the initiation codon of the riib gene of bacteriophage t4. | we have determined the sequence of a ribosome-protected region of t4 riib mrna labeled in vivo. the riib mutant hd263, which is temperature sensitive for translation, has an altered initiation codon (aua instead of aug). because wild-type and hd263 proteins have the same fmet peptide, this aua is used to initiate translation in the mutant riib mrna. we have also identified a six-base sequence which is complementary to the 3" end of the 16s rrna. | 1979 | 284393 |
| the effect of suppressive therapy of nontoxic diffuse goiter on serum levels of thyroxine, 3,5,3'-triiodothyronine and 3,3',5'-triiodothyronine. | we studied the effect of suppressive therapy with graded doses of thyroxine (t4) on serum levels of t4, 3,5,3'-triiodothyronine (t3) and 3,3',5'-triiodothyronine [rt3] in patients with diffuse, nontoxic goiter. for comparison and in order to elucidate the degree of suppression of the pituitary thyroid axis by t3 the effect of suppressive therapy with t3 was studied in the same type of patients. we found that t4 in serum rose significantly to a constant level during t4 treatment (0.10, 0.15 and 0 ... | 1979 | 284710 |
| the influence of propranolol on the extrathyroidal metabolism of 3,3',5'-triiodothyronine (reverse t3). | the effect of propranolol 80 mg daily on the metabolism of 3,3',5'-triiodothyronine (reverse t3, rt3), 3,3',5'-triiodothyronine (t3) and thyroxine (t4) was studied by means of a non compartmental kinetic method in seven females with severe pretreatment hypothyroidism. the patients were maintained euthyroid on a constant l-t4 replacement therapy. serum rt3 levels increased significantly during propranolol (p less than 0.02). this increase was explained by a decrease in metabolic clearance rate (m ... | 1979 | 284711 |
| recombination in phage t4 gene-43 (dna polymerase) mutants. | the effect of phage t4 gene 43 (dna polymerase) mutations on recombination between adjacent base pairs was measured in rii amber and opal mutants. the mutator allele tsl56 did not promote recombination frequencies at the two sites in which its effect was studied. the antimutator allele tscb87 caused slight or no reduction in recombination frequencies at five sites. | 1979 | 286143 |
| bacteriophage t4 riib protein synthesis with a temperature-sensitive mutation in the riib initiation codon. | in protein synthesis, the incorporation of an n-terminal formylmethionine residue is directed by an initiation codon. the most frequently used codon is aug, although initiation at gug and uug codons has also been observed. the hd263 mutation is an aug to aua change in the riib initiation codon. evidence is presented here that wild type and hd263 riib proteins, whether synthesized in vivo or in vitro, have identical fmet peptides. it is concluded that translation began at the aua mutant initiatio ... | 1979 | 286150 |
| dna replication by bacteriophage t4 proteins: role of the dna-delay gene 61 in the chain-initiation reaction. | 1979 | 289458 | |
| in vivo interactions of genes and proteins in dna replication and recombination of phage t4. | 1979 | 289460 | |
| late replication and recombination in the vegetative pool of t4. | the rates and extents of replication are the same for all members of the vegetative pool, whether already residing (progeny) or newly entered (superinfecting). thus, no member of the pool is sequestered in a replicative complex. amber n82 infections of nonpermissive host result in extensive breakdown of phage dna. the extent of fragmentation observed depends on the multiplicity of infection and whether phage ligase is present. hence, parental dna suffers single-strand nicks which can be repaired ... | 1979 | 289461 |
| a screening programme for congenital hypothyroidism: preliminary results. | highly sensitive and precise radioimmunoassays for thyroxine (t4) and thyrotropin (tsh) in dried blood spots on filter paper cards have been developed and are used to screen newborn infants for congenital hypothyroidism. blood spot tsh levels are measured in samples for which blood spot t4 levels fall in the lower 10 to 15 percent. there was a low recall rate of approximately one infant in every 550 screened. during a 17-month period 5225 infants have been screened for congenital hypothyroidism ... | 1979 | 290922 |
| the complete maps of bglii, sali and xhoi restriction sites on t4 dc-dna. | t4 dc-dna was digested with the restriction endonucleases bglii, sali and xhoi. overlaps in the three sets of fragments allowed the mapping of all restriction sites relative to each other along the t4 genome. | 1979 | 293460 |
| origins of phage t4 dna replication as revealed by hybridization to cloned genes. | [3h]thymidine-labeled progeny dna was isolated after infection of escherichia coli with two different bacteriophage t4 mutants. these strands were isolated shortly after the initiation of dna replication and hybridized to 15 different (ecori) t4 restriction fragments cloned in plasmid vectors. uniformly labeled t4 [32p]dna extracted from phage particles was cohybridized as a normalizing reference. the results obtained lead to the conclusions that, among the loci tested, initiation occurs predomi ... | 1979 | 293710 |
| breast milk thyroxine and not cow's milk may mitigate and delay the clinical picture of neonatal hypothyroidism. | thyroxine concentration was measured in human milk and cow's milk products by a specific radioimmunoassay. the mean (+/- s.e.m.) milk t4 concentration during the first 5 days postpartum was 0.7 +/- 0.3 microgram/dl (n = 11). the mean t4 concentration between 6-49 days postpartum rose to 3.1 +/- 0.2 microgram/dl (n = 108), falling after 50 days to a mean of 1.4 +/- 0.2 microgram/dl (n = 39). the mean (+/- s.e.m.) t3 concentration in breast milk in the first 50 days postpartum was 386 +/- 17 ng/dl ... | 1979 | 295567 |
| predicted secondary structures of four penicillin beta-lactamases and a comparison with two lysozymes. | we have predicted the secondary structures of four beta-lactamases (bacillus cereus, bacillus licheniformis, staphylococcus aureus, and escherichia coli r-tem) by the statistical method of chou & fasman as well as by the information theory method of garnier et al. the secondary structures of all four beta-lactamases are of the alpha/beta type (levitt & chothia's nomenclature), with helices at n- and c-termini. there are about eight short regions each of alpha-helical (30--50%) and beta-strand (1 ... | 1979 | 313376 |