| hydrogen exchange study of membrane-bound rhodopsin. i. protein structure. | structural parameters of rhodopsin in disc membrane preparations from frog and cattle were studied by hydrogen exchange methods. the method measures the exchange of protein amide hydrogens with water and can distinguish protons which are internally bonded from those which are hydrogen-bonded to water. the results show that about 70% of rhodopsin's peptide group protons are exposed to water. the identification of these groups as free peptides was made initially on the usual basis of the identity ... | 1977 | 21189 |
| hydrogen exchange study of membrane-bound rhodopsin. ii. light-induced protein structure change. | hydrogen exchange studies of rhodopsin in disc membranes demonstrated that photolysis induces changes in the protein itself. two different altered forms were detected. a late photointermediate in the bleaching sequence, which can be identified with metarhodopsin ii, displays accelerated exchange. subsequently, at the stage of fully bleached opsin, exchange becomes even slower than in rhodopsin. these changes involve only a small fraction of the protein's internally hydrogen-bonded peptide groups ... | 1977 | 21190 |
| nicotinamide adenine dinucleotide-specific glutamate dehydrogenase of neurospora. iv. the cooh-terminal 669 residues of the peptide chain; comparison with other glutamate dehydrogenases. | a sequence is presented for the cooh-terminal 669 residues of the nad-specific glutamate dehydrogenase of neurospora crassa. comparison of this sequence with those of the vertebrate glutamate dehydrogenases of chicken and bovine liver and with the nadp-specific enzyme of neurospora shows some similarities in sequences around residues previously identified as important for the function of these enzymes. these are: (a) the reactive lysine residue of low pk in the nadp and the vertebrate enzymes; ( ... | 1977 | 21191 |
| ribonucleic acid polymerase activity associated with purified calf rotavirus. | the presence of an rna-dependent rna polymerase is demonstrated in purified rotavirus particles. optimum polymerase activity was found between 45 to 50 degrees c, at ph 8, and in the presence of 10 mm-magnesium ions. the polymerase product was highly sensitive to pancreatic rnase (97%) in low or high salt concentration. the enzyme was activated by edta treatment of intact particles or heat shock. the similarities between reovirus, blue-tongue virus and rotavirus polymerases are discussed. | 1977 | 21225 |
| the interactions of bromocriptine and lergotrile with dopamine and alpha-adrenergic receptors. | bromocriptine and lergotrile, which are clinically used as antiparkinsonian (ap) agents, compete for the binding of h3-dopamine, h3-apomorphine, and h3-haloperidol to striatal membrane sites. lergotrile has a higher affinity for the h3-dopamine binding to bovine striatal membranes than bromocriptine. lergotrile and bromocriptine are almost equipotent in competing for the binding of h3-apomorphine to rat striatal membranes, but bromocriptine is more potent in competing for the binding of h3-halop ... | 1977 | 21229 |
| estimation of the plasma protein binding of drugs by size exclusion chromatography at medium pressure (150 lb in-2: 1-03 mpa). | | 1977 | 21250 |
| tetrazole analogs of phenylalanine derivatives as tyrosine hydroxylase inhibitors. | eight new tetrazole analogs of phenylalanine derivatives in which the carboxyl group was replaced by a tetrazole ring were synthesized. at a concentration of 2.5 time 10(-5) m, each compound exhibited greater than 50% inhibition of tyrosine hydroxylase activity. | 1977 | 21283 |
| toxoplasma gondii-vertebrate cell interactions. i. the influence of bicarbonate ion, co2, ph and host cell culture age on the invasion of vertebrate cells in vitro. | a controlled-environment culture system was used to show that both physical and biologic parameters can influence the penetration of vertebrate cells by toxoplasma gondii. the optimum bicarbonate ion concentration for the penetration of bovine embryo skeletal muscle (besm) cells is 36.25 mm. higher or lower bicarbonate ion concentrations are increasingly inhibitory to penetration. as co2 increases in the range from 0.5-3.7 mm, penetration is progressively inhibited. no relationship was found bet ... | 1977 | 21287 |
| comparative studies on membranes from bovine choroid plexus and rat kidney cortex. | | 1977 | 21337 |
| heat stable inhibitors produced in raw milk. | twenty raw farm milk samples were tested for inhibitory substances before and after being kept at room temperature until the ph fell to less than 6.3 but greater than 6.2. the tests were done using the idf-method and the commercial thermocult method. in both methods b. stearothermophilus var. chalidolactis is used as the test organism. in two instances a thermostable inhibitor was produced with an inhibitory potential greater than 0.01 iu/ml penicillin standard. the idf-method was found unsuitab ... | 1977 | 21382 |
| multiple forms of enzymes. | | 1977 | 21492 |
| differetial staining of glycosaminoglycans, utilizing bacterial chondroitinase and chondrosulphatase. | a histochemical method for the differentiation of glucosaminoglycans, utilizing bacterial chondroitinase abc and chondro-4- and -6 sulphatases, and staining with alcian blue, is presented. the method is applied on human tissues with known glucosaminoglycan content (ganglion cyst, umbilical cord, foetal cartilage, adult cartilage) and the results are compared with the results obtained by staining with alcian blue at controlled ph levels, with or without prior digestion with bovine testicular hyal ... | 1977 | 21513 |
| effect of phospholipid liposomes of the regulation of cerebral metabolism. | | 1977 | 21529 |
| factors affecting cyanoborohydride reduction of aromatic schiff's bases in proteins. | reductive alkylation of bovine serum albumin (bsa) and wool by a aromatic aldehydes and sodium cyanoborohydride has been investigated. the aldehydes used were chosen to allow convenient quantitative measurement of binding by ultraviolet spectroscopy. alkylation of bsa occurred primarily at two highly reactive sites. variation of time, ph, reactant concentration, and addition of urea had little effect on the extent of alkylation of bsa. however, more extensive alkylation was achieved in buffered ... | 1977 | 21538 |
| energy-dependent exchange of k+ in heart mitochondria. k+ influx. | | 1977 | 21617 |
| energy-dependence exchange of k+ in heart mitochondria. k+ efflux. | | 1977 | 21618 |
| enzyme systems involved in phosphorylation and dephosphorylation of two endogenous phosphoproteins in neuronal membranes. | | 1977 | 21619 |
| studies of a reactive histidine of dyphosphopyridine nucleotide-linked isocitrate dehydrogenase from bovine heart. | | 1977 | 21624 |
| properties of soluble somatostatin-binding protein. | a soluble somatostatin-binding protein was detected in the cytosol fractions of various rat, human and bovine tissues. maximum binding occurred at ph8.0-8.5 and was ca(2+)-dependent. the specific binding of somatostatin per 10mug of cytosol protein from 12 rat tissues ranged between 36 and 15%, and 3% for peripheral blood cells. there was also substantial binding in cytosol from human anterior pituitary and liver, and bovine anterior pituitary. the specific binding in rat and human plasma in the ... | 1977 | 21654 |
| fractionation of membrane vesicles. ii. a method for separation of membrane vesicles bearing different enzymes by free-flow electrophoresis. | free-flow electrophoresis was used to subfractionate membrane vesicles from calf thymocyte plasma membranes. the fractionation resulted in a separation of vesicle populations bearing four different enzymes: alkaline nitrophenyl-phosphatase (orthophosphoric-monoester phosphohydrolase (alkalin optimum) ec 3.1.3.1), gamma-glutamyltransferase (ec 2.3.2.2), (mg2+ + na+ + k+)-atpase (atp phosphohydrolase, ec 3.6.1.3) and acyl-coa:lysophosphatidylcholine acyltransferase (acyl-coa:1-acylglycero-3-phosph ... | 1977 | 21691 |
| interaction of folic acid with ribonuclease a. | | 1977 | 21693 |
| lectins in the hemolymph of japanese horseshoe crab, tachypleus tridentatus. | the hemolymph of the japanese horseshoe crab, tachypleus tridentatus contains lectins which agglutinate mammalian erythrocytes. affinity chromatographic purification of the lectins using bovine submaxillary gland mucin-conjugated sepharose resulted in the separation of the lectins into four fractions; one major and three minor lectins. protein subunits revealed by polyacrylamide gel electrophoresis and the immunoprecipitin line of these lectins against antiserum to crude lectins were unique to e ... | 1977 | 21704 |
| quinonoid dihydropterin reductase from beef liver. | quinonoid dihydropterin reductase has been purified from beef liver. this enzyme has been shown to be indistinguishable from the reductase of sheep liver in molecular weight, subunit composition, and terminal residues. both beef and sheep liver reductases possess acyl isoleucine as the n-terminal residue. use of improved isolation techniques, including general ligand affinity chromatography, has yielded enzyme preparations of much higher specific activity than previously reported. affinity chrom ... | 1977 | 21726 |
| improved hydrolysis of urinary 17-hydroxycorticosteroid glucuronides with beta-glucuronidase from helix pomatia, on adding sodium sulfate. | sodium sulfate increases the hydrolysis of urinary 17-hydroxycorticosteroid glucuronides with beta-glucuronidase preparations derived from helix pomatia because it removes the inhibitory activity of urinary high-molecular-weight substances. for maximum hydrolysis of urinary 17-hydroxycorticosteroid glucuronides, the hydrolysis 5 ml of urine, 0.5 ml of 2 mol/liter acetate buffer (ph 5.0) should be conducted in the presence of sodium sulfate (final concentration: 80 g/liter) with (a) 600 fishman u ... | 1977 | 21763 |
| nucleotide-binding sites on the coupling adenosine triphosphatase from ox heart mitochondria proceedings. | | 1977 | 21818 |
| conformational changes induced by ionic strength and ph in two bovine myelin basic proteins. | the structures of two biologically different myelin proteins, a1 from the central nervous system and p2 from the peripheral nervous system, were investigated. both proteins were isolated from nerve tissues. conformational changes in the homogeneous proteins were examined in aqueous solutions by means of circular dichroism measurements. the secondary structures of both proteins proved to be very stable between ph 2.5 and ph 11.7. unlike the p2 protein, the a1 protein is stable up to ph 13 without ... | 1977 | 21842 |
| thermodynamics of the electrochemical proton gradient in bovine heart submitochondrial particles. | the electrical and chemical components of the electrochemical proton gradient of submitochondrial particles can be monitored simultaneously by continuously recording optical signals from the probes oxonol-vi and 9-aminoacridine. either respiration or atp hydrolysis causes a red shift in the absorption spectrum of oxonol-vi indicative of a membrane potential and a decrease of the fluorescence of 9-aminoacridine indicative of a ph gradient. the magnitude of the membrane potential and ph gradient f ... | 1977 | 21873 |
| a benzoaquinolizine derivative with a neuroleptic-like action on cerebral monoamine turnover. | | 1977 | 21955 |
| the effect of hot-boning on glycolysis in beef muscle. | | 1977 | 21994 |
| establishment of the hosts of bloodsucking mosquitoes in abkhazia. 3. fertility of females of mass mosquito species feeding on warm-blooded and cold-blooded animals. | | 1977 | 22029 |
| dopaminergic stimulation of cyclic amp accumulation and parathyroid hormone release from dispersed bovine parathyroid cells. | the effects of dopaminergic agonists and antagonists have been studied in dispersed bovine parathyroid cells. dopaminergic agonists caused a transient 20- to 40-fold increase in cellular cyclic amp and a 2- to 3-fold increase in parathyroid hormone release. dose-response relationships were similar for cyclic amp accumulation and hormone release, whether studied by increasing agonist concentration or by increasing concentration of antagonist with constant agonist. the effects on the dopamine rece ... | 1977 | 22076 |
| activation of guanylate cyclase by superoxide dismutase and hydroxyl radical: a physiological regulator of guanosine 3',5'-monophosphate formation. | partially purified soluble rat liver guanylate cyclase gtp pyrophosphate-lyase (cyclizing), ec 4.6.1.2 was activated by superoxide dismutase (superoxide: superoxide oxidoreductase, ec 1.15.1.1). this activation was prevented with kcn or glutathione, inhibitors of superoxide dismutase. guanylate cyclase preparations formed superoxide ion. activation by superoxide dismutase was further enhanced by the addition of nitrate reductase. although guanylate cyclase activity was much greater with mn2+ tha ... | 1977 | 22077 |
| guanylate cyclase and cyclic gmp-dependent protein kinase in the brain (author's transl). | | 1977 | 22100 |
| cigarette smoke activates guanylate cyclase and increases guanosine 3',5'-monophosphate in tissues. | the gaseous phase of cigarette smoke induced a 2- to 36-fold increase in the activity of guanylate cyclase in supernatant and particulate fractions from various rat and bovine tissues over basal activity. the characteristics of this phenomenon paralleled those of the activation of guanylate cyclase by nitric oxide, which is a component of tobacco smoke. | 1977 | 22126 |
| penicillin allergy. kinetics of penicilloylation of serum albumins by various penicillins. | | 1977 | 22216 |
| translation by bacterial cells of messenger rna for interferon of animal origin. | escherichia coli, strain ab 1157, cells are capable of translating human, mouse, and chicken messenter rna for interferon with production of interferon of the corresponding specifity. this translation occurs in the presence of serum. the activity of the resulting interferon decreased in parallel to dilution of the original mrna preparation, upon multiple ulitization of the mrna solution, as well as upon reduction of the interferon- producing activity of cells-donors of mrna due to prolonged stor ... | 1977 | 22228 |
| reaction of antibody with gamma-glutamyl transpeptidase. i. isolation of the human enzyme and inhibition of its activity by antiserum. | use of a four-step method of purification from human kidneys yielded gamma-glutamyl transpeptidase with specific activity 330 times higher than activity in the homogenate. the enzyme from human liver was also purified, and from urine two fractions of it were separated. from rabbits immunized with the enzyme from human kidney, antiserum was obtained which inhibits and precipitates the human-derived enzyme, and in a low degree the enzyme purified from bovine kidneys. this inhibition was independen ... | 1977 | 22320 |
| self-association of troponin. | ox muscle troponin was shown by equilibrium- and velocity-sedimentation studies to undergo concentration-dependent dissociation into its constituent subunits as well as self-association in imidazole buffers, ph 6.9. the extent of troponin association was found to be strongly dependent on ionic strength and also to exhibit a dependence on ph and temperature; under conditions physiological in regard to ph, temperature and ionic strength the extent of polymerization of troponin is considerable in 2 ... | 1977 | 22325 |
| the state of aggregation of red deer (cervus elaphus l.) beta-lactoglobulin preparations near neutral ph. | 1. the state of aggregation of four red-deer (cervus elaphus l.) beta-lactoglobulin preparations and a control ox beta-lactoglobulin a preparation was studied by sedimentation-equilibrium experiments at ph 6.5 and 20 degrees c. 2. three of the deer preparations and the ox control each behaved as a monomer-dimer system, with a value of log k (where k is the association constant in litres/mol) in the range 5.4-5.5. 3. when one of these deer preparations was examined in the presence of dithiothreit ... | 1977 | 22326 |
| tritium effect in peroxidation of ehtanol by liver catalase. | 1. simultaneous determination of the rate of appearance of 3h in water from (1r)-1-3h1 ethanol and the rate of acetaldehyde formation in the presence of rat or ox liver catalase under conditions of steady-state generation of h2o2 allowed calculation of the 3h isotope effect. the mean value of 2.52 obtained for rat liver catalase at 37 degrees c and ph 6.3-7.7 was independent of both ethanol concentration and the rate of h2o2 generation over a wide range. at 25 degrees c a slightly lower mean val ... | 1977 | 22327 |
| the effect of methemoglobin on the inhibition of cytochrome c oxidase by cyanide, sulfide or azide. | | 1977 | 22333 |
| comparative studies of bovine carbonic anhydrase in h2o and d2o. stopped-flow studies of the kinetics of interconversion of co2 and hco3. | | 1977 | 22343 |
| effects of dietary vitamin b-2 and vitamin e on the delta9-desaturase and catalase activities in the rat liver microsomes. | the effects of dietary vitamin b-2 and vitamin e on delta9-desaturation of stearoyl-coa, catalase, glutathione peroxidase, superoxide dismutase and electron transport components in rat liver microsomes have been investigated. delta9-desaturase activities were decreased on diets deficient of vitamin b-2, e and supplemented with e. among the peroxide-scavenging enzymes, only the catalase activity in microsomes correlates significantly with delta9-desaturase activity. in vitro addition of bovine c ... | 1977 | 22349 |
| the polymerization pattern of zinc(ii)-insulin at ph 7.0. | sedimentation equilibrium experiments were conducted at ph 7.0 using solutions of bovine insulin containing 2 mol of zinc(ii) ions per six base-mol of insulin. a detailed analysis of these results revealed the existence of a stable zinc-insulin hexamer together with linked polymerization reactions. specifically these are a background polymerization of zinc-free insulin as previously described by jeffrey et al. ((1976) biochemistry 15, 4660--4665) and a slight tendency for the zinc-insulin hexame ... | 1977 | 22351 |
| detection of 15-hydroxyprostaglandin dehydrogenase in bovine mesenteric blood vessels. | | 1977 | 22356 |
| regional distribution of alpha-noradrenergic receptor binding in calf brain. | | 1977 | 22392 |
| ocular antigens vii. the influence of freund's complete adjuvant and corneal structural glycoprotein in xenogeneic keratoplasty. | | 1977 | 22446 |
| inactivation of catalase by chloride. | | 1977 | 22458 |
| activation of adrenal tyrosine hydroxylase by atp and other nucleotides. | | 1977 | 22459 |
| natural protein atpase inhibitor from candida utilis mitochondria. binding properties of the radiolabeled inhibitor. | | 1977 | 22460 |
| binding interactions of ergot alkaloids with monoaminergic receptors in the brain. | the interactions of ergot alkaloids and of other drugs with dopamine (da) and alpha-adrenergic receptors were investigated. the tested ergot alkaloids inhibit synaptosomal tyrosine hydroxylase activity and reverse the apomorphine-elicited inhibition of synaptosomal tyrosine hydroxylase activity. thus, ergot alkaloids interact as both agonists and antagonists with the presynaptic da receptors. ergot alkaloids also compete effectively for the binding of 3h-da and 3h-haloperidol to bovine striatal ... | 1978 | 22480 |
| effects of culture milieus on the development of mouse blastocysts in vitro. | various culture milieus were examined for their support of mouse blastocyst development. two important variables were the time at which human cord serum was added to the medium and the concentration of amino acids. in the best medium. eagle's minimum essential medium (fortified with six times the usual amino-acid concentration plus 20 percent fetal bovine serum, replaced after 48 hr with human cord serum), 83 percent of the blastocysts shed the zona pellucida, 58 percent developed to the early e ... | 1977 | 22483 |
| serum-derived immunosuppressive substances. ii. an evaluation of various sources for an endogenous regulator of lymphocyte activation. | four published methods (ion-exchange chromatography, heat, molecular sieving and alcohol fractionation) for the preparation of fractions of normal sera and tissues which possess immunosuppressive activity are compared. human and bovine serum and human, bovine and ovine tissues including spleen, placenta and thymus were investigated as sources of substances which were immunosuppressive when added to mixed lymphocyte cultures and when injected into mice 24 h before antigenic challenge. cohn fracti ... | 1977 | 22495 |
| the formation, degradation, and function of cyclic nucleotides in the nervous system. | | 1977 | 22509 |
| tissue fractionation in neurobiochemistry: an analytical tool or a source of artifacts. | | 1977 | 22511 |
| highly acidic proteins in bovine liver. | | 1977 | 22541 |
| calf liver nuclear n-acetyltransferases. purification and properties of two enzymes with both spermidine acetyltransferase and histone acetyltransferase activities. | calf liver contains two nuclear n-acetyltransferases which are separated by chromatography on hydroxylapatite. both acetyltransferase a and acetyltransferase b will transfer acetate from acetyl-coa to either histone or spermidine. the same protein catalyzes the reaction with both substrates; this is shown by a constant ratio of spermidine to histone activity over a 5,000-fold purification and identical heat denaturation kinetics for both spermidine and histone acetyltransferase activity with eac ... | 1978 | 22543 |
| cerebrocortical necrosis in ruminants: an attempt to identify the source of thiaminase in affected animals. | | 1977 | 22559 |
| a simple method to determine gammaglutamyl-cyclotransferase activity in erythrocytes. | a new method for the determination of erythrocyte gammagct is described. the method follows the release of alanine from gammaglutamyl alanine by a series of linked reactions that result in the oxidation of nadh to nad. the ph optimum for human erythrocyte gammagct was found to be 9.0, and the km for gammaglutamyl alanine was found to be 2.3 x 10(-3) m. human erythrocytes had the highest activity of all the species studied (human, rabbit, dog, sheep, cattle, chicken). | 1978 | 22573 |
| arginases of mouse brain and liver. | | 1977 | 22583 |
| the influence of proteins on the transport of tetracyclines proceedings. | | 1977 | 22664 |
| binding of sulfonylurea derivatives to bovine serum albumin: part i. binding of spc--703, tolbutamide, glibornuride and glipizide. | | 1977 | 22846 |
| enamel microhardness and fluoride uptake underneath fermenting and non-fermenting artificial plaque. | washed cells of streptococcus sanguis were used to form artificial plaque on the surface of bovine enamel and incubated underneath buffer solutions, initial ph 6, for 36 h at 37 degrees c. the decrease in the microhardness of the enamel surface under fermenting "plaque" could be prevented with fluoride. enamel under a fermenting "plaque" took up significantly more (p less than 0.0u) fluoride than enamel under a non-fermenting "plaque" (initial f- in buffer: 10 parts/10(6)). the artificial plaque ... | 1977 | 22924 |
| analysis of the major histocompatibility complex in syrian hamsters. i. skin graft rejection, graft-versus-host reactions, mixed lymphocyte reactions, and immune response genes in inbred strains. | five inbred strains of syrian hamsters (mesocricetus auratus) were examined for the presence of disparity at a genetic region similar to the major histocompatibility complex in other species. vigorous reciprocal alloreactions developed in several strain combinations, which resulted in acute skin graft rejection, strong mixed lymphocyte reactions, and potent graft-versus-host reactions. in addition, we found evidence for an immune response gene which controls the antibody response to bovine serum ... | 1978 | 22947 |
| analysis of the major histocompatibility complex in syrian hamsters. ii. linkage studies. | the genetic control of the histocompatibility antigens that induce strong alloreactions in syrian hamsters was examined. genetic studies revealed that the alloantigens involved in skin graft rejection, graft-versus-host reactions, and mixed lymphocyte reactions are under dominant single gene control and that these genetic loci are closely linked. these data suggest that this strong histocompatibility locus (i) may represent the major histocompatibility complex equivalent in this species, and thi ... | 1978 | 22948 |
| the first cleavage site in pepsinogen activation. | by incubation of porcine, bovine, canine, or chicken pepsinogens and calf prochymosin with pepstatin at ph 2.5, the first active protein generated on activation is trapped in an inactive complex. the first activation peptide liberated from porcine pepsinogen has been identified as residues 1-16 whereas that from prochymosin is derived from residues 1-27. this suggests that pepsin and chymosin are not formed by one-step conversions from their zymogens, but by (different) sequential, activation me ... | 1977 | 22994 |
| passive ion permeability of the chromaffin-granule membrane. | 'ghosts' of bovine chromaffin granules, in which the complex mixture of proteins and solutes normally found in the granule matrix is replaced by buffered sucrose are osmotically sensitive. they shrink when the osmotic pressure of the suspension medium is increased, and swell if solute entry is facilitated by the addition of ionophores. swelling in the presence of ionophores has been used to investigate the passive ion permeability of these membranes. they have a very low permeability to k+ ions ... | 1977 | 23117 |
| proton electrochemical gradient and phosphate potential in submitochondrial particles. | the aerobic uptake of inorganic ions, such as 86rb+ or 125i-, by submitochondrial particles, is about one order of magnitude lower than the uptake of organic ions, such as acridines or 8-anilino-1-naphthalene sulphonate. the values of deltaph, the transmembrane ph differential, and deltapsi, the transmembrane membrane potential are between 60 and 100 mv when calculated on the inorganic ions and between 150 and 240 mv when calculated on the organic ions. the discrepancy between the deltaph and d ... | 1978 | 23158 |
| evidence for the different responses of delta9-, delta6- and delta5-fatty acyl-coa desaturases to cytoplasmic proteins. | microsomes prepared from the livers of 4-week-old rats were, after extraction with 0.1 m potassium phosphate buffer, ph 7.4, unable to catalyse either the delta6 desaturation of alpha-linolenic acid (9c.12c.15c., 18 : 3) into 6c.9c.12c.15c., 18 : 4 or the delta5 desaturation of eicosatrienoic acid (8c.11c.14c., 20 : 3) into arachidonic acid (5c.8c.11c.14c., 20 : 4). both these enzymes only showed full activity after incubation of the microsomes with either the 100 000 x g supernatant fraction or ... | 1978 | 23171 |
| distribution of catecholamines in the cattle tick boophilus microplus. | | 1977 | 23237 |
| the interrelations between the transport of sodium and calcium in mitochondria of various mammalian tissues. | addition of ruthenium red to mitochondria isolated from brain, adrenal cortex, parotid gland and skeletal muscle inhibits further uptake of ca2+ by these mitochondria but induces little or no net ca2+ efflux; the further addition of na+, however, induces rapid efflux of ca2+. the velocity of the na+-induced efflux of ca2+ from these mitochondria exhibits a sigmoidal dependence on the na+. addition of na+ to mitochondria exhibiting the most active na+-dependent efflux of ca2+ (brain and adrenal c ... | 1978 | 23291 |
| inhibition of cholesterol biosynthesis and acetyl-coenzyme a synthetase by bovine milk and orotic acid. | | 1977 | 23394 |
| acid lipase-esterase (4-methylumbelliferyl oleate hydrolase) of white matter localized in oligodendrocyte cell bodies. | | 1977 | 23413 |
| acid-base indices in ovine blood and cerebrospinal fluid. | by means of the astrup apparatus (blood microsystem bms 2) acid-base indices in blood and cerebro-spinal fluid of clinically healthy merino sheep at the age of one year (15 head) and of two or three years (41 head) were determined. blood collected anaerobically from v. jugularis and liquor collected by means of the suboccipital punction in heparinized syringes and/or caplaris and liquor collected by means of the suboccipital punction in heparinized syringes and/or capillaries were examined immed ... | 1977 | 23602 |
| in vitro effect of some naturally secreted hormones on tyrosine hydroxylase activity of beef adrenal medulla. | | 1977 | 23694 |
| conformational study of calf brain tubulin. | | 1978 | 23729 |
| the weaning of calves. ii. effects of the diet on various characteristics of the ruminal fluid. | | 1977 | 23811 |
| effects of monensin sodium on the ph and on the concentration of volatile fatty acids of the ruminal fluid. | | 1977 | 23812 |
| interaction of ribonuclease a with aqueous 2-methyl-2,4-pentanediol at ph 5.8. | the interactions between ribonuclease a and solvent components in aqueous 2-methyl-2,4-pentanediol (mpd) have been investigated by differential refractometry and light scattering at ph 5.8, i.e., conditions similar to those used to crystallize the protein from this solvent system. application of multicomponent thermodynamic theory shows that, at all solvent compositions up to 50% (v/v) mpd, the protein is preferentially hydrated; i.e., addition of ribonuclease to the mixed solvent leads to an in ... | 1978 | 23825 |
| purification and properties of a cyclic amp-independent protein kinase from calf thymus nuclei. | a phosphoprotein kinase (atp : protein phosphotransferase, ec 2.7.1.37) from calf thymus nuclei was purified by deae-cellulose chromatography, hydroxyapatite, and sepharose 6b gel filtration. the enzyme is a cyclic amp-independent protein kinase by the following criteria: (a) the protein kinase did not bind cyclic amp; (b) no inhibition of activity was obtained with the heat-stable protein kinase inhibitor from rabbit skeletal muscle; (c) the regulatory subunit of cyclic amp-dependent protein ki ... | 1978 | 23835 |
| purification and properties of polynucleotide kinase of calf thymus. | polynucleotide kinase (atp:5'-dephosphopolynucleotide 5'-phosphotransferase, ec 2.7.1.78) has been purified approx. 1500-fold from calf thymus. this enzyme phosphorylates 5'-hydroxyl termini in dna using atp as phosphate donor. rna is phosphorylated at a much lower rate than dna. the reaction requires the presence of a divalent cation, preferably mg2+ or mn2+ and is sensitive to sulfhydryl antagonists. the optimum ph for enzyme activity is 5.5. enzyme activity is inhibited by low concentrations ... | 1978 | 23843 |
| preliminary studies with l-asparaginase bound to implantable bovine collagen heterografts: a potential long-term, sustained dosage, antitumor enzyme therapy system. | in this study, l-asparaginase has been bound to collagen heterografts derived from carotid bovine arteries. the immobilization procedure utilizes both non-covalent and covalent interactions to fix the enzyme. binding of the enzyme to the graft material was shown to the ph dependent, with optimum binding occurring at ph 6.0 and ph 8.5. amidohydrolysis by the bound enzyme exhibited zero-order kinetic behavior at substrate saturating conditions. total apparent asparaginase activity expressed by the ... | 1977 | 23873 |
| alpha-noradrenergic receptors in the brain: differential effects of sodium on binding of 3hagonists and 3hantagonists. | | 1978 | 23888 |
| distribution and some properties of cathepsin b in the bovine eyes. | | 1978 | 23951 |
| bovine adrenal medulla tyrosine hydroxylase: separation of the native and aggregate forms. | | 1978 | 23962 |
| depression of cell-mediated immunity following inoculation of trichinella spiralis extract in the mouse. | mice pretreated with trichinella spiralis extract (tse), or infected with the parasite, rejected primary skin allografts in 18-23 days and secondary allografts in 12-16 days. mice pretreated with saline or with bovine serum albumin (bsa) rejected the primary allografts in 12-18 days and did not accept the secondary grafts. inoculation of increasing doses of parental spleen cells from mice pretreated with saline or with bsa in f1 hybrids produced proportionately stronger graft-versus-host reactio ... | 1978 | 23994 |
| effect of external environmental factors on the morphology of spiroplasma citri. | spiroplasma citri was examined by electron microscopy for morphological changes when maintained under a variety of conditions. pplo serum fraction maintained spiral and helical morphology of s. citri at ph values of 8.0, 7.5, and 7.0, but only partially at ph 6.0 and 5.0. the absence of pplo serum fraction resulted in round, deteriorated cells at all ph values tested. bovine serum albumin (bsa), phytone, soluble starch, potato starch, spermine, lipid-extracted pplo serum fraction, and lipid-extr ... | 1978 | 24042 |
| characterization of protein inhibitors of guanylate cyclase activation from rat heart and bovine lung. | | 1978 | 24051 |
| deltaph and catecholamine distribution in isolated chromaffin granules. | | 1978 | 24053 |
| an investigation into the viability of broth cultures of the t1 strain of mycoplasma mycoides sub-species mycoides. | the t1 broth vaccine against contagious bovine pleuropneumonia can only be stored for four weeks at +4 degrees c because after that time the titre of mycoplasma mycoides sub-species mycoides falls below the minimal vaccinating dose. an investigation into the death of these organisms during the stationary growth phase was made. the culture medium in which the vaccine was prepared was found to contain adequate nutrients. control of the ph by the addition of koh was shown to preserve the viability ... | 1978 | 24242 |
| clinical and metabolic consequences to cattle of rumen overdosing with di-ureido iso-butane (duib). | di-ureido iso-butane (duib) was overdosed on three occasions to two year-old bullocks, under experimental conditions. six g/kg live weight of duib was mixed manually into the rumen contents formed by a predominantly hay diet (10 kg) with added concentrates (2 kg). marked clinical signs were observed for 72 h before recovery. food and water intake were interrupted and a smell of ammonia saturated the accommodation. blood concentrations of urea-nitrogen increased, while glucose fell; a metabolic a ... | 1978 | 24244 |
| atp-induced release of vasopressin associated with phosphorylation of isolated bovine neurohypophyseal secretory granule membranes. | secretory granules isolated from ox neurohypophyses released their content of vasopressin in the presence of atp and mg2+. a half maximal atp concentration of 0.25 mm was found. ca2+ was not necessary for the effect. high concentrations of adp, amp and itp were shown to mimic the effect of atp. utilizing this effect of atp combined with iodonitrotetrazolium treatment to make mitochondria heavier, a method is described to obtain granule "ghosts" in a purified form. they were shown to be phosphory ... | 1978 | 24318 |
| comparative investigations concerning the influence of pilocarpine and aceclidine on the glucose consumption of surviving ocular tissues (author's transl). | conservative glaucoma therapy repeated during a whole lifetime raises the question of medicamentuous tolerance. recently, cultivation of normal lens epithelia and of iris tissue has made possible determination of metabolic functions with and without application of different medicaments. preceding experiments revealed a diminution in glucose consumption by these tissues after addition of pilocarpine. comparative studies show 0.25 g/100 ml medium to be maximum concentration of aceclidine allowing ... | 1978 | 24356 |
| the binding of copper ions to copper-free bovine superoxide dismutase. kinetic aspects. | the kinetics of reconstitution of bovine superoxide dismutase from cu2+ and the copper-free enzyme have been studied by activity, u.v.-absorption, electron-paramagnetic-resonance and pulsed-nuclear-magnetic-resonance measurements. the process appears to be first-order up to 80% completion in most conditions, and is ph-dependent, with an apparent pk of 6.5. u.v.-absorption and solvent proton relaxation rate measurements show that fast binding of cu2+ occurs, and the initial ligands are likely to ... | 1978 | 24441 |
| nuclear magnetic resonance studies on the binding of substrate, coenzymes, and effectors to glutamate dehydrogenase. | | 1978 | 24461 |
| electron spin resonance and nuclear relaxation studies on spin-labeled glutamate dehydrogenase. | the reaction of glutamate dehydrogenase with two different stable nitroxides (spin labels) is reported. the two compounds contain a carbonyl and an iodoacetamide group as their reactive parts. the carbonyl compound inactivates the enzyme by the formation of a 1:1 covalent complex after nabh4 reduction of an intermediate schiff's base. evidence indicates that the enzyme is modified at lysine-126 in the active site. the electron spin resonance (esr) spectrum of spin-labeled enzyme indicates a high ... | 1978 | 24462 |
| the mechanism of oxidation of reduced nicotinamide dinucleotide phosphate by submitochondrial particles from beef heart. | 1. oxidation of nadph by various acceptors catalyzed by submitochondrial particles and a partially purified nadh dehydrogenase from beef heart was investigated. submitochondrial particles devoid of nicotinamide nucleotide transhydrogenase activity catalyze an oxidation of nadph by oxygen. the partially purified nadh dehydrogenase prepared from these particles catalyzes an oxidation of nadph by acetylpyridine-nad. in both cases the rates of oxidation are about two orders of magnitude lower than t ... | 1978 | 24468 |
| effects of melanin on tyrosine hydroxylase and phenylalanine hydroxylase. | melanin inhibited rat liver phenylalanine hydroxylase, but activated tyrosine hydroxylase from rat brain (caudate nucleus), rat adrenal glands, and bovine adrenal medulla. activation of tyrosine hydroxylase by melanin was demonstrated with the extensively dialyzed enzyme and in suboptimal concentrations of the substrate (tyrosine) and the cofactor (6-methyltetrahydropterin). tyrosine hydroxylase from rat brain was activated by melanin more markedly than that from rat adrenal glands. purified and ... | 1978 | 24474 |
| characteristics of galactosyl and fucosyl transfer to bovine rhodopsin. | | 1978 | 24547 |
| binding of thyrotropin to receptors in fat tissue. | | 1978 | 24565 |