methods for assessing steroid-receptor effect on rna synthesis in isolated nuclei. 1975162990
cyclic amp and cyclic gmp content and binding in malignancy. 1975163087
antiviral drugs for the neonate--the risk-benefit ledger. 1975163110
metabolism, function and clinical aspects of vitamin d.briefly reviewed herein are some of the contemporary findings on the metabolism of vitamin d, and the biochemical and physiological effects of this steroid in the animal. certainly the most accepted major action of vitamin d is to enhance the intestinal absorption of calcium. historically, there is also considerable evidence that the vitamin d is required for the resorption of calcium from bone, thereby aiding in maintaining normal serum calcium levels. increasing evidence is becoming available ...1975163168
radiolabeling of proteins and viruses in vitro by acetylation with radioactive acetic anhydride.we describe a convenient, rapid, and reproducible method for labeling proteins in vitro by acetylation with [3h] or [14-c]acetic anhydride dissolved in small amounts of anhydrous dioxane. the reaction is carried out at neutral ph and does not require the use of detergents, water-immiscible organic solvents, oxidizing, or reducing agents. thus undesirable solvent-induced alterations in protein structure and biological activity are minimized. a method for calculating the specific activity of the p ...1975163253
uptake of 3-o-methyl-d-glucose into cultured human glioma cells. 1975163292
evaluation of dye exclusion and colony inhibition techniques for detection of polyoma-specific, cell-mediated immunity.cellular immunity directed against polyoma virus-induced antigen was observed with c3h/hej splenic lymphoid cells from mice sensitized by a short-term immunization schedule with syngeneic polyoma 4198 and 4198v tumor cells. polyoma specificity of the response was shown by demonstration that splenic cells from dba/2j animals with polyoma virus-induced tumors were cytotoxic for the c3h 4198 and 4198v cells, but not for the l-m cell, another cell line of c3h origin. the polyoma-specific response in ...1975163318
microbial assimilation of hydrocarbons. i. the fine-structure of a hydrocarbon oxidizing acinetobacter sp.1. the fine-structure analysis of the hydrocarbon oxidizing microorganism, acinetobacter sp., demonstrated a cytoplasmic modification resulting from growth on paraffinic and olefinic hydrocarbons. 2. intracytoplasmic hydrocarbon inclusions were documented by electron microscopy with chemical identifications obtained by gas chromatography and x-ray diffraction. 3. these results demonstrate the ability of a microorganism to accumulate hydrocarbon substrates intracellularly which, in turn, indicate ...1975163624
benzo(alpha)pyrene effects on mouse epithelial cells in culture.the effect of benzo (a) pyrene on the growth in culture of 5 mouse epithelial cell strains was examined. these epithelial cells are highly sensitive to the cytotoxic action of benzo (a)-pyrene. in addition, the activity of the benzol (a) pyrene-metabolizing system, aryl hydrocarbon hydroxylase, is low but highly iducible by the carcinogen. as the sensitivity of a cell strain to the cytotoxic action of benjo (a) pyrene decreased, the inudcibility of the hydroxylase also decreased,. however, a str ...1975163692
potentiation of the effect of histamine by pge2 in the isolated perfused rabbit kidney and guinea-pig lung. 1975163751
prevention of gram-negative bacillary pneumonia using polymyxin aerosol as prophylaxis. ii. effect on the incidence of pneumonia in seriously ill patients.all 744 patients admitted to a respiratory-surgical intensive care unit (rsicu) were included in a prospective study of the effects of a polymyxin (2.5 mg/kg body wt/day in six divided doses) or a placebo aerosol sprayed into the posterior pharynx and tracheal tube (if present), during 11 alternating 2-mo treatment cycles. the incidence of upper airway colonization in the rsicu with pseudomonas aeruginosa was 1.6% during the polymyxin treatment cycles (total 374 patients) and 9.7% during the pla ...1975163848
collagen in the human lung. quantitation of rates of synthesis and partial characterization of composition.the presence of collagen in lung is fundamental in normal lung structure and function. methods have been developed to examine human fetal and adult lung collagen with respect to its composition and synthesis. the second trimester fetal lung has a large number of cells per unit lung mass (36.6 plus or minus 2.7 mug dna/mg dry wt) and relatively small amounts of collagen (17.0 plus or minus 5.3 mug collagen/mg dry wt). the number of cells per unit lung mass in the adult lung (11.1 plus or minus 3. ...1975163849
radioreceptor assay for human chorionic gonadotropin.a sensitive radioreceptor assay capable of detecting 100 pg of human chorionic gonadotropin has been developed using ovarian receptors and (125i)hcg. the dose-response curves of a series of urine and serum samples from pregnant women were linear and parallel to standard curves of 2nd international standard hcg and purified hcg when logit of percent bound was plotted against log dose. potency estimates of pregnancy sera, measured by radioreceptor assays, were approximately 2 times greater than th ...1975163971
genetic heterogeneity in xeroderma pigmentosum: complementation groups and their relationship to dna repair rates.fibroblast strains from 12 patients with xeroderma pigmentosum had lower than normal rates of dna repair, as determined by autoradiographic studies of ultraviolet-induced unscheduled nuclear dna synthesis. the nuclei in binuclear cells, obtained by fusing fibroblasts from certain pairs of these strains, had a greater rate of dna repair than the nuclei of either strain's unfused mononuclear cells. these results indicate that complementary corrections of the strains' repair defects had occurred in ...1975164028
androgen-induced nuclear accumulation of the estrogen receptor.the effect of androgens on the nuclear uptake of both tritiated estradiol (3h-e2) and the estrogen receptor was studied in immature rat uteri. it was demonstrated that in vitro preincubation of immature rat uteri with various androgens (1 mum to 50 mum) followed by incubation with 3h-e2 (20 nm) resulted in a greatly decreased specific nuclear uptake of 3h-e2. non-androgenic steroids had no effect. it was also confirmed that 5alpha-dihydrotestosterone (dht) causes the accumulation of the estrogen ...1975164064
progesterone-binding proteins: in vitro binding and biological activity of different steroidal ligands.progesterone-binding proteins from human, rabbit, sheep and guinea pig myometrial cytosol, all induced with oestradiol, as well as from pregnant guinea pig myometrium and plasma were investigated. the physico-chemical properties of the oestradiol-induced binding proteins were very similar in all the species studied. in all, 63 steroids were tested for their ability to compete with tritiated progesterone for the binding sites on these six proteins and their relative affinities were determined. th ...1975164094
the influence of age of cell cultures on the production of foot-and-mouth disease antigen. brief report. 1975164159
the synthesis and turnover of virus-specific polyadenylated rna in polyoma-infected cells. 1975164192
the biogenesis of mitochondrial membranes in the yeast saccharomyces cerevisiae.membrane lipids of yeast mitochondria have been enriched by growing yeast cells in minimal medium supplemented with specific unsaturated fatty acids as the sole lipid supplement. using the activity of marker enzymes for the outer (kynurenine hydroxylase) and inner (cytochrome c oxidase and oligomycin-sensitive atpase) mitochondrial membranes, arrhenius plots have been constructed using both promitochondria and mitochondria obtained from o2-adapting cells in the presence of a second unsaturated f ...1975164216
[isolation of the virus of transmissible gastroenteritis of swine from cell cultures and antigenic comparison of 2 american strains]. 1975164273
local and systemic response after simultaneous intranasal inoculation of temperature-sensitive mutants of parainfluenza 3, ibr and bovine adenovirus 3.triple seronegative calves were exposed by the nasal route to three (ts) mutants of bovine respiratory viruses (pi3, ibr, adeno3). after a single exposure, they responded with significant levels of serum antibodies to the three viruses. nasal antibodies were demonstrated for pi3 and adenovirus antigens. the failure to demonstrate nasal antibodies to ibr may be due to lack of sensitivity of the procedure used. when reexposed six weeks later, calves had sharp increases in levels of serum antibodie ...1975165126
studies on cyclic amp metabolism in human epidermoid carcinoma (hep-2) cells.cultured human epidermoid carcinoma (hep-2) cells were found to contain a highly responsive, catecholamine-sensitive adenyl cyclase activity in cellfree preparations. by contrast, cyclic amp levels in intact hep-2 cells were at best only marginally increased by catecholamines under a variety of conditions. the lack of an intact cell response could not be accounted for by escape of cyclic amp to the medium, excessive phosphodiesterase activity, inactivation of the catecholamine, or by unusual kin ...1975165357
thyroid-stimulating hormone and cyclic adenosine 3',5'-monophosphate in the regulation of thyroid gland function.the initial step in tsh action reflects binding of the hormone to specific receptor sites on the plasma membrane. such binding has been studied using plasma membranes, homogenates, isolated thyroid cells grown in culture, and thyroid slices. 3-h- and iodinated tsh preparations have been used; the latter have been prepared using both chloramine-t and lactoperoxidase. some of the discrepancies reported in the literature might reflect the different thyroid and hormone preparations and the variable ...1975165359
a sensitive bioassay for the determination of human plasma acth levels.a sensitive bioassay for the measurement of plasma acth is presented. the use of silicic acid adsorption of plasma, with a subsequent acid wash and aqueous acetone desorption, was successful in removing those substances which had interfered with the steroidogenic response of dispersed adrenal cells when unextracted plasma was employed. this extraction procedure extracted 72-76% of acth present in plasma. two pg acth1-39 could be consistently detected. alpha-hacth1-39 and alpha-pacth1-39 exhibite ...1975165419
letter: light induced change in rod outer segment membrane fluidity. 1975165628
glucagon and adenylate cyclase: binding studies and requirements for activation.solubilization of myocardial adenylate cyclase abolished responsiveness to glucagon and catecholamines, two of the hormones which activate the membrane-bound enzyme. adenylate cyclase freed of detergent by deae-cellulose chromatography continues to remain unresponsive to hormone stimulation. however, adding purified bovine brain phospholipids--phosphotidylserine and monophosphatidylinositol--restored responsiveness to glucagon and catecholamines, respectively. 125-i-glucagon binding appeared to ...1975165684
results of radiation treatment of naturally occurring animal tumors. 1975166056
adenovirus infection in two calves.two 2-week-old calves with pyrexia, diarrhea, and subsequent dehydration were treated symptomatically for 1 week, but without favorable response. at necropsy, foci of necrosis were found in the abomasum and rumen of each calf. the small and large intestineswere dilated by grayish, turbid fluid. numerous large amphophilic, intranuclear inclusions in endothelial cells of blood vessels in the abomasum and rumen, in endothelial cellsof the adrenal cortical sinusoids and renal glomeruli, and in intes ...1975166059
the ultrastructure of the sensory end-organs (baroreceptors) in the atrial endocardium of young mini-pigs.light and electron microscopical studies on pig hearts have confirmed the presence in the right and the left atrial endocardium of distinct circumscribed, unencapsulated end-organs (baroreceptors) associated with 4-9 mum thick nerve fibres. the myelin sheath terminates before the entrance of the nerve into the end-organ. the regular presence of thin axon profiles containing clusters of small agranular vesicles, both around the thick nerve fibre and in the periphery of the end-organs, suggests a ...1975166065
the crystal structure of bonito (katsuo) ferrocytochrome c at 2.3 a resolution. ii. structure and function.the structure analysis of bonito heart ferrocytochrome c was carried out at 2.3 a resolution by x-ray diffraction, and a kendrew-type skeletal model was built up. this molecule has an overall egg shape, 35 a in height, 30 a in width and 23 a in thickness; the 5th ligand of the heme iron atom is the n-epsilon atom of the his-18 imidazole ring and the 6th is the met-80 sulfur atom. distinct alpha-helix regions are found between the n-terminus and reside 11, between 60 and 69, and between 90 and th ...1975166072
the influence of sodium, potassium and lanthanum on amino acid release from spinal-medullary synaptosomes. 1975166144
chemotherapeutic nitroheterocycles. 18. 2-(5-nitro-2-imidazolylmethylene)-1-indanones, -1-tetralones, and -acetophenones substituted by aminoalkoxy groups.2-(5-nitro-2-imidazolylmethylene)-1-indanones, -1-tetralones, and -acetophenones substituted by aminoalkoxy groups and related compounds (41-69, table ii) were synthesized and their antimicrobial activities were evaluated (table iii). some of these compounds (e.g. 47, 52, and 59) suprisingly exhibited a broad antibacterial spectrum including proteus species and pseudomonas aeruginosa. extraordinary antitrichomonal activities could also be observed in vitro (mic of compound 59, 0.0004 pg/ml) and ...1975166185
purification and properties of moniezia cytochrome c550. 1975166788
interferon production in mice by the capsular polysaccharide of klebsiella pneumoniae.the capsular polysaccharide of klebsiella pneumoniae (cps-k) type 1, kasuya strain, induces interferon production in the blood of mice when injected intravenously. cps-k resembles bacterial endotoxin (lipopolysaccharide) in the time pattern of interferon production, with peak levels 2h after injection. cps-k on a weight basis exhibits a more potent interferon-inducing effect than lipopolysaccharide. the active substance responsible for the interferon-inducing activity of cps-k is the neutral cps ...1975166921
newer knowledge in comparative virology--its contribution to human health other comparative sciences, and despite its recent beginning comparative virology has already contributed useful applications and observations to human health research. teachings derived from the study of marek's disease found application in that of burkitt's lymphoma, and may lead to a possible vaccine against the human disease. equally useful information came from the study of canine distemper in the development of a chorio-allantoic membrane attenuated measles vaccine, and in our knowled ...1975167504
the effect of arginine deprivation on the cytopathogenic effect and replication of human cytomegalovirus.arginine is necessary for the development of the cytopathogenic effect of human cytomegalovirus in human embryonic fibroblasts. it is also required, though in greater concentrations, for the production of infective virions, the requirement being at an early stage of replication. inhibitor studies suggested that this block in replication caused by arginine deficiency was prior to the formation of viral dna. withdrawal of arginine from the medium 24 or 48 hours after infection resulted in a declin ...1975167690
differential effects of lipid depletion on membrane sodium-plus-potassium ion-dependent adenosine triphosphatase and potassium ion-dependent phosphatase.the phospholipid-dependence of the (na-++k-+)-dependent atpase (adenosine triphosphatase) (ec and associated k-+-dependent phosphatase activity (ec have been compared. unlike the (na-++k-+)-dependent atpase activities, the k-+-dependent phosphatase activities of a number of different preparations were not closely correlated with their total phospholipid contents. after partial lipid depletion with a single extraction in lubrol w the residual atpase and phosphatase activities we ...1975167727
improvements in the thin-layer chromatography of natural products. i. thin-layer chromatography of the aflatoxins.during the period which has elapsed since the aflatoxins were first isolated, one of the main problems has been the separation of the individual aflatoxins in pure form from aflatoxin-containing extracts. this separation has been best effected by thin-layer chromatography, and in this paper we describe how some of the difficulties may be overcome by using an appropriate combination of solvent system and silica gel preparation. for the examination of aflatoxin-containing extracts from the mycelia ...1975168220
the immune response to infection with vaccinia virus in mice. i. infection and the production of antibody neutralizing cell-associated and cell-free virus.the onset, duration and magnitude of antibody responses to a poxvirus infection were examined. mice were inoculated intravenously with the wr strain of vaccinia virus and developed pocks on their tails. the number of pocks was related to the size of the inoculum. virus was detectable in the spleen and infected mice were subsequently immune to intravenous and intra-nasal challenge. sera of infected animals neutralized both cell-free and cell-associated virus. antibody against cell-free virus appe ...1975168248
regulation of sensitivity to beta-adrenergic stimulation in induction of pineal n-acetyltransferase.stimulation by isoproterenol causes large increases in the activity of rat pineal n-acetyltransferase (arylamine acetyltransferase or acetyl-coa:arylamine n-acetyltransferase, ec after a variable lag period. lengthening periods of exposure to light cause rapid increases in the sensitivity of pineal n-acetyltransferase to induction by isoproterenol. this supersensitivity, which develops gradually over a 12 hr period, is correlated with increasingly longer lag periods in the induction of ...1975168570
the role of cell surface changes in rna tumor virus-transformed cells. 1975169020
a simplifying concept in tumor virology: virus-specific "pleiotropic effectors". 1975169084
structural studies on two adenovirus 2-sv40 hybrids containing the entire sv40 genome. 1975169085
kinetic parameters of tryptophan: trna ligase catalyzed atp-(32p) pyrophosphate exchange as an approach to extimation of the order of substrate binding. 1975169163
effect of klebsiella pneumoniae enterotoxin on intestinal transport in the rat.the effects on intestinal transport of either a semipurified preparation of enterotoxin elaborated by klebsiella pneumoniae or similaryly prepared control material were tested by marker perfusion studies in the small intestine of rats. at a concentration of 2 mg/ml, the enterotoxin produced net secretion of water, na, and cl in both jejunal and ileal segments; hco3 transport was not affected. net secretion was evident within 30 min after intorduction of the toxin and was maximal after 90 min. th ...1975169297
a spin-label study on fusion of red blood cells induced by hemagglutinating virus of japan.fusion of red blood cells (rbc) induced by hemagglutinating virus of japan (hvj) has been studied using a phosphatidylcholine spin label. the spin label was readily incorporated and diffused into the lipid bilayer portion of the viral envelope. the exchange broadening in the electron spin resonance (esr) spectrum of densely labeled virus disappeared rapidly when the virus was mixed with rbc at 37 degrees. the spectrum gradually approached that of the host cell spin labeled with the phosphatidylc ...1975169884
ultrastructure of human bronchiolo-alveolar cell carcinoma.ultrastructural features were correlated with a series of special staining reactions in eight cases of bronchiolo-alveolar carcinoma. ultrastructural, all tumors were similarly composed of large cells with abundant cytoplasm and small nuclei in close contact with each other. straight membranes or complex interdigitations occurred within adjacent tumor cells, attached to each other by scattered desmosomes. microvilli or cilia abutted from free surfaces of the cells, and were noted in different st ...1975169987
dispersion along fiber tracts and in the coupling between tracts and a cortical network.dispersion in a neuronal coritcal network was modeled using csmp, a continuous systems modeling program. the signal dispersion over pathways was simulated by use of a serial product approximating the convolution integral. the program was written in a sufficiently general format to be applied to a variety of biological signals. calculated signals from a fiber tract and activation of a cortical network were compared with experimental data from cats. the network consists of excitatory cells in a fo ...1975170035
some properties of androgen-binding activity in rat testis.high-affinity (ka approximately equal to 5 x 10(8) m-1 for testosterone) androgen-binding activity in rat testis was shown to have a rapid dissociation rate constant (t1/2 = 3 min, 0 degrees c, 30% glycerol buffer) using dextran-coated charcoal to separate bound from free hormone. because of this fact, exchange of endogenous and labeled hormone was complete in the assay incubation time (16 h, 0 degrees c) and scatchard plots of the high-affinity binding data were shown to measure total as contra ...1975170151
splenocyte plaque assay for the detection of murine leukemia virus.a modified xc assay for murine leukemia virus (mulv) employing splenocytes taken directly from the animal is described. this modification can be more than 1000 times more sensitive than xc plaque assays employing tissue extracts. this technique should lend itself readily to the quantitation of infectious mulv in defined populations of lymphoid cells.1975170622
"unbound" ligand adsorption on dextran-coated charcoal: practical considerations. 1975171517
information contained in the amino acid sequence of the alpha1(i)-chain of collagen and its consequences upon the formation of the triple helix, of fibrils and crosslinks.the molecule of type i collagen from skin consists of two alpha1(i)-chains and one alpha2-chain. the sequence of the entire alpha1-chain comprising 1052 residues is summarily presented and discussed. apart from the 279 residues of alpha1(i)-cb8 whose sequence has been established for rat skin collagen, all sequences have been determined for calf skin collagen. in order to facilitate sequence analysis, the alpha1-chain was cleaved into defined fragments by cyanogen bromide or hydroxylamine or lim ...1975171554
predicted distribution of nad domain among glycolytic enzymes. 1975171581
[effect of the method of cell disintegration on the aspartate kinase activity of preparations from bacillus polymyxa var. ross].the influence of methods of cell disintegration of bac. polymyxa on aspartate kinase activity (ec was examined. the disruption by means of the hews press yielded a more active preparation as compared with ultrasonic disintegration. the supernatant treatment with streptomycin sulphate increased the preparation activity 2-fold. dialysis of the fraction with a high activity of aspartate kinase inactivated the enzyme by 80--85%. the relationship between the aspartate kinase activity and the ...1975171645
surface ruffles as markers for studies of cell transformation by rous sarcoma virus.confluent chick embryo fibroblasts infected with the ts68 mutant of rous sarcoma virus were examined by scanning electron microscopy at the permissive (36 degrees) and nonpermissive (41 degrees) temperatures for transformation. infected cells shifted from 41 degrees to 36 degrees undergo a change in shape from elongated to rounded. this process is preceded by the appearance of surface ruffles on the cell. these surface ruffles are not observed on cells maintained at 41 degrees, appear as early a ...1975171654
adenosine, amp, cyclic amp, theophylline and the action and production of erythropoietin.erythropoiesis, as measured by the uptake of 59fe into plethoric mice, is stimulated by adenosine, amp, cyclic amp, and dibutyryl cyclic amp, but not by cytidine, its nucleotides or cyclic gmp. this stimulation is erythropoietin dependent, because it is prevented by anti-erythropoietin. theophylline neither stimulates erythropoiesis nor potentiates the action of erythropoietin on bone marrow cells in plethoric mice. theophylline does potentiate the production of erythropoietin in rats following ...1975171682
methyltrienolone, a specific ligand for cellular androgen receptors.methyltrienolone (r 1881), 17beta-hydroxy-17alpha-methyl-estra-4,9,11-trien-3-one, a very active androgen, binds specifically to rat prostate cytosol with a higher affinity than androstanolone. unlike the physiological hormone, however, it is not bound by human sex steroid plasma binding protein, sbp. this specific ligand is thus a useful tool for the detection of elusive androgen receptors and for their study, for instance, in human tumors where interference from plasma contamination has to be ...1975171806
different effects on renal and submaxillary renin release after blockade of the renin system in mice.ingibition of the angiotensin i converting enzyme with sq 20,881 results in a rapid marked increase in plasma renin concentration in mice. the maximum effect is short-lasting, but the values are still elevated 2 hours after the injection, the time course being similar to that previously found in rats. the relative increase is the same in normal and sialo-adenectomized mice. the plasma renin concentration of nephrectomized mice with their submaxillary glands intact is, however, totally uninfluenc ...1975171913
foreign body removal: a new role for the fiberoptic bronchoscope.artificial and animal lung models initially were used to investigate the removal of foreign bodies from the tracheobronchial tree with the flexible fiberoptic bronchoscope. different extraction instruments (claw, basket, forceps, and balloon catheter) were passed separately through the channel of the bronchofiberscope, and tested for usefulness prior to human application. the fogarty balloon catheter served as a valuable aid in dislodging impacted objects so that the operator could then grasp th ...1975172001
cytoplasmic poly(adp-ribose) polymerase during the hela cell cycle. 1975172024
the mechanism of assimilation of constituents of chylomicrons, very low density lipoproteins and remnants - a new theory. 1975172080
proceedings: corticotrophin production by rat adenohypophysial segments in vitro. 1975172177
[identification of camp dependant protein kinases in human lymphocytes].chromatographic purification by "deae" cellulose resolves the camp binding proteins in human lymphocytes into three parts. in presence of mg++ each one possesses camp dependent protein-kinase activity, one of them showing allosteric characteristics.1975172248
[resistance to association of antibiotics (polymyxin and penicillin) in relation to cell concentration of two bacterial species in the same inoculum. complementary inoculum effect].dense suspensions of sa. typhi (polys penr) and of st. aureus (polyr pens) proliferate on gelose medium added with the two antibiotics only if the inoculum is mixed. the growth is probably due to the partial neutralization of the antibiotics following the formation of complexes between these antibiotics and some constituents of the two strains.1975172250
origin of lymphoid lines established from mixed cultures of cord-blood lymphocytes and explants from infectious mononucleosis, burkitt lymphoma and healthy donors.lymphocytes were explanted from ebv-seropositive donors including peripheral blood of infectious mononucleosis patients, healthy donors and ebv-genome-carrying cells from burkitt lymphoma (bl) biopsies or nude mouse-passaged, bl-biopsy-derived lines. the explanted cells were mixed with fresh cord-blood lymphocytes from mice of the opposite sex. in all categories of derived lines, cord-blood cell progeny was predominant, as judged by the sex marker and other associated markers. only one bl biopsy ...1975172457
a simple method for freeze-fracture of monolayer cultures.a simple method is described for the freeze-fracture in situ of monolayer cultures grown on gold carriers coated with a thin layer of silicon monoxide. preliminary observations on 3t3 mouse embryo fibroblasts indicate that this technique exposes large areas of cell membrane, making it possible to determine how areas of membrane specialization are related to the cell as a whole and to regions of cellular interaction. 3t3 cells cultured on silicon monoxide show no modification of growth properties ...1975172516
longitudinal, serological study of cytomegalovirus infections in nurses and in personnel without patient contact.sera were obtained at intervals from 172 hospital employees for measurement of cytomegalovirus (cmv) complement fixation (cf) and indirect hemagglutination antibody. no fourfold rises or falls in titer were seen over a 19- to 27-month period among 71 employees with initially positive cmv cf titers. the concurrence rate between the cmv cf and the indirect hemagglutination antibody tests in identifying seronegative personnel was 96%. five seroconversions were identified during an average follow-up ...1975172528
[metabolism and actions of vasoactive substances in the lung. (3) the effects of atp, cyclic amp, dibutyryl cyclic amp on tracheal muscle responsiveness]. 1975172682
inhibition of hepatic lipogenesis by adenine nucleotides.incubation of liver slices and isolated liver cells with adenosine cyclic-3',5'-monophosphate at concentrations which inhibit lipogenesis was found to expand the pool size of the noncyclic adenine nucleotides in the intact cells of the preparations. this observation led to studies which demonstrated that adenosine and adenosine-5'-monophosphate also inhibited lipogenesis and expanded the adenine nucleotide pool size. it is proposed but not proven that the increase in intracellular nucleotides pr ...1975172757
induction of gene mutations and chromosomal aberrations by simian virus 40 in cultured mammalian cells.induction of gene mutations by sv40 was studied in aneuploid human and chinese hamster cells. in chinese hamster cells sv40-induced chromosome aberrations were also studied. sv40 penetrated into the cells of both lines and induced synthesis of the t antigen. the efficiency of infection in chinese hamster cells was tested additionally by their ability to form colonies in medium lacking the serum growth factor. the maximal number of cells with serum growth factor independence was observed on the f ...1975172787
persistence of cmv genome in lymphoid cells after congenital infection. 1975172796
the partial purification of clostridium perfringens beta attempt was made to purify clostridium perfringens beta toxin. crude toxin prepared by ammonium sulphate precipitation of culture supernatants was purified by chromatography on sephadex g50, sephadex g100 and deae cellulose. this material, although highly purified was not homogeneous on polyacrylamide gel electrophoresis. it had a toxicity of 800 000 mouse mlds/mg n, a typical protein absorption spectrum in the uv region, an iso-electric point of 5, 6 and the main component had a molecular ma ...1975172828
a study of the sequences of chicken embryo lethal orphan (celo) virus dna present in a transformed hamster cell line with use of specific fragments of the virus genome. 1975173080
[diabetogenic and atherogenic effects of glucose].tests were set up on 59 albino male-rats with reproduced functional overstress and depletion of the insular system of the pancreas thorough a long-term (for 50, 100 days) peroral introduction of glucose (2 g/100 g body weight, every other day) and with and alloxan-induced diabetes (achieved by poisoning the animals with a 2.5% alloxan solution, 15 mg/100 g administered in a single dose intraperitoneally). a comparison of the data obtained ascertained the presence of a number of similar pathobioc ...1975173088
specific cleavage of sendai virus nucleocapsid protein subunits during virus storage.the alteration of whole sendai virus and especially of its nucleocapsid polypeptides, during storage of the virus at 4 degree c in the allantoic fluids in which it was cultivated, has cultivated, has been studied by sodium dodecyl sulfate gel electrophoresis. during virus storage the nucleocapsid protein subunits with a molecular weight of 60,000 and the putative inner envelope protein with a molecular weight of 38,000 were mainly affected. both virus components were partially degraded to smalle ...1975173260
blood flow in the small intestine of cat and man as analyzed by an inert gas washout technique.using a recently developed 85kr-elimination technique, blood flow and flow distribution of the human small intestine have been investigated in patients during abdominal surgery. total intestinal blood flow was estimated to be 38 +/- 4 ml per min and 100 g of intestinal tissue (mean +/- se: n = 19), jejunal blood flow being slightly higher than ileal. in 14 of these patients muscularis blood flow was determined to be 21 +/- 2 ml per min and 100 g of muscularis tissue and mucosal-submucosal blood ...1976173617
absence of poly (a) from the infective rna of nodamura virus.with the exception of phage qbeta, the rnas of all the other small icosahedral rna viruses so far examined contain a poly (a) tract. this tract has been implicated in the infectivity of poliovirus rna. we have now shown that nodamura virus, a divided genome virus from which infective rna can be extracted, does not contain any poly (a) tracts. this evidence with nodamura virus shows that poly (a) is not a necessary requirement for the infectivity of virus rna molecules.1976173797
inhibition of glutamate-elicited accumulation of adenosine cyclic 3',5'-monophosphate in brain slices by alpha, omega-diaminocarboxylic acids. 1975173984
structural alterations of the junctional region in extraocular muscle of dystrophic mice. ii. hypertrophy of the neuromuscular junctional apparatus.the fine structure of end-plate abnormalities was studied in the bar harbor c57bl/6jdy2j dystrophic mouse. a marked increase in area and volume of junctional sarcoplasm was often apparent. such hypertrophied end-plates were often penetrated by networks of axonal terminal branches. at times, pseudopod-like extensions of the junctional sarcoplasm encompassed and made protracted synaptic contact with the incoming axon. such apparent remodeling of the neuromuscular apparatus might represent a compen ...1976174437
[electron microscopical investigation of rhinoscleroma (author's transl)].a boy from togo with a resistent rhinoscleroma was observed. the specific granuloma was examinated by histological and electron microscopic methods. the plasma cells form fibrillary material or guttate russel bodies in the rough endoplasmatic reticulum. the morphology of mikulicz-cells and klebsiella rhinoscleromatis is described. the cells are supposed to be (histiocytic) macrophages. the surface of the germs is coated with a fimbria-like radiate substance which in the vacuoles of the cells is ...1975174498
[infectious and hyperthermic diseases in early pregnancy]. 1975174510
murine leukaemia virus expression in the akr following thymectomy.thymectomy effectively prevents the development of spontaneous lymphoma in the akr but how this effect is achieved remains to be determined. one possible mechanism, namely suppression of genomic expression of the oncogenic murine leukaemia virus now seems unlikely since levels of the group specific mulv antigen were in comparision with their sham operated controls unaltered in both neonatally and adult thymectomized akr.1975174705
[immunologic results obtained with an experimental system oftransplantable colonic tumors. possible applications of these results to human intestinal tumors].intestinal cancers, morphologically very close to human colo-rectal adeno-carcinoma, have been induced by dimethylhydrazine in inbred rats. graftable lines have been obtained from 5 primary intestinal tumors, and 3 cell lines have been cultivated from the grafts. this model was used to demonstrate carcinofetal antigen(s) on the surface of the intestinal cancer cells. circulating antibodies against tumor-associated antigen(s) have been found in tumor-bearing rats. cancer enhancement was regularly ...1975174767
[stimulation of sv40 virus replication in chinese hamster kidney cells by treatment of the cells with mitomycin c].the production of virions by chinese hamster kidney cells infected with sv 40 dna is increased 10 to 100 fold by mitomycin c treatment. this observation has been confirmed for different cell clones. the optimum concentration of mitomycin c has been determined.1975174828
viruses as teratogens.there is nothing unique about rubella viruses or cytomegaloviruses. they are classic teratogens and, in this respect, not only follow but exemplify most of the principles of human teratology.1975174856
[bactericidal dosie-activity relationships with e. coli, k. pneumoniae and staph. aureus (author's transl)].in investigations into the dosis-activity relationships of bactericidal antibiotics used against e. coli, k. pneumoniae and staph. aureus four types of activity could be demonstrated. the penicillin type shows almost no improvement in bactericidal activity despite increasing the dosage above a certain level. an increase in concentration of aminoglycoside antibiotics led to a more rapid killing of the bacteria. in cefalotin there was a linear dosis-activity relationship: rising concentrations of ...1976174881
control of uterine estrogen receptor levels by progesterone.the mechanism by which progesterone antagonizes estrogenic stimulation of uterine growth was examined in the immature rat. rats received daily injections of 2.5 mug estradiol (e) for 2 days and on day 3 either 2.5 mug e or 2.5 mug e plus 2.5 mg of progesterone (p). the quantity of nuclear and cytoplasmic estrogen receptor was determined by [3h]estradiol exchange at various intervals after injection of e or e + p. in both groups, nuclear receptor estrogen complex (rne) increased dramtically one h ...1976174899
demonstration of steroid specific hormone receptors by chromatography. 1976174953
lung lamellar bodies lack certain key enzymes of phospholipid metabolism.palmitoyl coa-glycerol-3-phosphate acyltransferase, phosphatidate phosphohydrolase, and phospholipase a were assayed in subcellular fractions of rat lung, including lamellar bodies, the putative site of storage and secretion of lung surfactant. the specific activity of each of these enzymes in lamellar bodies was relatively low and could be entirely accounted for by a small contamination of the lamellar bodies fraction by microsomes, as quantitated by the presence of the microsomal marker reduce ...1976175233
opposing regulatory influences of cyclic guanosine monophosphate and cyclic adenosine monophosphate in the control of cardiac muscle contraction.the effects of acetylcholine chloride (ach) and isoproterenol (iso) on myocardial levels of guanosine 3', 5'-monophosphate (cyclic gmp) and adenosine 3', 5'-monophosphate (cyclic amp) and on force of contraction were studied in elelctrically driven isolated rabbit atria. incubation of atria with tyrode's solution containing ach (5 x 10(-7) m) produced significant decreases in contractile force that were associated with significant elevations in atrial cyclic gmp levels. atrial levels of cyclic a ...1975175413
occurrence of reo-like calf viruses in young children with acute gastroenteritis. diagnoses established by electron microscopy and complement fixation, using the reo-like virus as the course of a six-month-study of acute gastroenteritis in children of ages up to six years, a reo-like virus was found in 54 per cent of the faecal specimens obtained at an early stage of the disease, using electron microscopy as screening test. by means of a concentrated complement fixation antigen, composed of a related calf diarrhoea virus cultivated in tissue culture, the rise in titre was found to be significant in 96 per cent of the patients whose faeces contained the reo-like virus. ...1976175639
immunological control of virus-associated tumors in man: a perspective. 1976175948
investigations on isolated islets of langerhans in vitro. influence of temperature changes during preparation on some parameters of insulin metabolism.pancreatic islets of wistar rats were prepared by digestion with collagenase and then washed and isolated at three different temperatures (4, 22 and 37 degrees c). the efficiency of washing with regard to proteolytic and collagenolytic activities in the wash buffer was not affected by the temperatures used. the islet thiol:protein-disulphide oxidoreductase activity (ec was apparently unchanged, whereas washing temperatures lower than 37 degrees c resulted in a diminished insulin content ...1975176103
evidence for a parathyroid hormone-independent calcium modulation of phosphate transport along the disclose a parathyroid-independent calcium modulation of phosphate transport along the nephron, the effect of increasing plasma calcium concentration to subnormal levels in rats 6 days after parathyroidectomy (chronic ptx) was studied. fractional phosphate reabsorption was significantly increased. the whole kidney response to calcium infusion was similar whether or not the thyroid gland was removed, which suggests that calcitonin is not involved. the micropuncture study indicated an increase ...1976176176
use of horseradish peroxidase to study the antagonism of clostridium welchii (cl. perfringens) type d epsilon toxin in mice by the formalinized epsilon prototoxin. 1976176185
mitogen induction of murine c-type viruses. i. analysis of lymphoid cell subpopulations.we reported previously in vitro induction of endogenous c-type viruses from normal mouse spleen cells by lipopolysaccharide (lps) as well as by combination treatment with concanabalin a and 5-bromo-2'-deoxyuridine (con a/brdu). to identify the cell types sensitive to virus induction and to study the relationship of mitogenicity to virus induction we have compared t cell populations (balb/c thymus cells and cortisone-resistant thymus cells), b cell populations (nu/nu spleen cells and lymph node c ...1976176274
growth in semisolid agar medium of human cord leukocytes freshly transformed by epstein-barr virus.the semisolid agar method for the selective growth of transformed cells was applied to investigations of epstein-barr virus (ebv) transformation. when 1 x 10(5) human umbilical-cord blood leukocytes were seeded in agar medium immediately after ebv exposure, about 100 colonies developed in each dish. the occurrence of colonies correlated well with dilutions of ebv inoculum. these colonies were composed of lymphoblasts, were positive for ebv-determined nuclear antigen immunofluorescence, and cons ...1976176377
biochemical studies on mitochondria isolated from normal and neoplastic tissues of the mouse mammary gland.mitochondria isolated from spontaneous and transplanted mammary adenocarcinomas of two strains of mice were compared, by various biochemical criteria, to mitochondria from mammary glands of midpregnant or hormonally stimulated, cancer-free mice. the specific activities of several mitochondrial enzymes including cytochrome oxidase, alpha-glycerophosphate oxidase, and succinate dehydrogenase were twofold to threefold lower, whereas the activity of monoamine oxidase was two fold higher in tumor mi ...1976176382
stimulation of growth of a transplantable hepatoma in rats by parenteral nutrition.young buf rats of similar ages were inoculated with the transplantable morris hepatoma no. 7777. at 4 weeks after inoculation, 1 group was given total iv (parenteral) feeding at high caloric and nutritional levels for 2 weeks. such total iv feeding (hyperalimentation) of rats stimulated a more rapid tumor growth in the host. in addition, the tumors from rats fed parenterally for 2 weeks had higher mitotic activity and larger areas of necrosis, which indicate that iv feeding caused the tumor to u ...1976176398
analysis of simian virus 40 wild-type and mutant virions by agarose gel electrophoresis.intact wild-type simian virus 40 particles can be separated and resolved from a temperature-sensitive mutant and from a number of other viruses by agarose gel electrophoresis. the relative mobilities of the viruses appear to be a function of both virion size and surface composition. the virions of a temperature-sensitive strain of simian virus 40, tsb204, have significantly greater mobility than those of wild-type simian virus 40, when electrophoresis was conducted toward the cathode at ph 5.0. ...1976176451
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