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Recombination of ciliary dyneins of Tetrahymena pyriformis with the outer fibers was investigated using turbidimetry, co-sedimentation analysis and electron microscopy. As reported by Gibbons, 30S dynein could recombine with the outer fibers, while 14S dynein did to so a lesser extent. At acidic pH, however, most of th... |
The acetylenic substrate, D-2-amino-4-pentynoic acid (D-propargylglycine), was oxidatively deaminated by hog kidney D-amino acid oxidase[EC 1.4.3.3], with accompanying inactivation of the enzyme. The flavin which was extracted by hot methanol from the inactivated enzyme was identical with authentic FAD by thin-layer ch... |
To clarify the properties and functions of a trypsin inhibitor from Japanese barley in comparison with the inhibitor from Pirkka barley, an inhibitor was isolated from the barley Hordeum distichum L var. emend Lamark by extraction with 1% NaCl, ammonium sulfate fractionation and repeated chromatography on DEAE-cellulo... |
Adenine and pyridine nucleotide levels as well as those of phosphate, phosphocreatine, lactate, pyruvate, beta-hydroxybutyrate, acetoacetate, glucose, and glycogen were measured in histologically defined parietal and mucous cell sections of biopsies of dog gastric mucosa at rest, and in various secretory states. As a r... |
The binding of triiodothyronine by Rana catesbeiana tadpole tail fin, tail muscle, kidney, and liver cytosol was studied using dextran-coated charcoal to separate bound and free hormone. A metal ion dependency was suggested by the fact that EDTA decreased the binding of triiodothyronine 80 to 90% in tail fin and tail m... |
Cytochrome P-450 from bovine adrenocortical mitochondria exists in three forms of molecular weight: 850,000 (protein 16), of one-half (protein 8), and of one-quarter of this value (protein 4). The forms of the enzyme are named according to the number of subunits and all appear to be active in converting cholesterol to ... |
Clostridium perfringens sialidase was purified by affinity chromatography. Kinetic properties of the enzyme were examined with sialyllactose and with mixed sialoglycolipids (gangliosides) as substrates. With the latter substrate in 0.01 M Tris-acete in the absence of strong electrolyte, the pH optimum for enzymatic act... |
Reduced coenzyme Q-cytochrome c reductase from bovine heart mitochondria (complex III) was incorporated into phospholipid vesicles by the cholate dialysis procedure. Soybean phospholipids or mixtures of purified phosphatidylcholine, phosphatidylethanolamine, and cardiolipin could be used. Oxidation of reduced coenzyme ... |
Crude particulate preparations obtained from anaerobic, light-grown cells of Rhodopseudomonas spheroides have been shown to possess a significant level of sn-glycerol-3-phosphate acyltransferase (EC 2.3.1.15) activity. In contrast to the enzyme from Escherichia coli, the R. spheroides glycerophosphate acyltransferase h... |
NADH-coenzyme Q reductase from bovine heart mitochondria (complex I) was incorporated into phospholipid vesicles by the cholate dialysis procedure. Mixtures of purified phosphatidylcholine and phosphatidylethanolamine were required. Oxidation of NADH by coenzyme Q1 catalyzed by the reconstituted vesicles was coupled to... |
Thyroxine-binding globulin was isolated from human plasma by ammonium sulfate fractionation, chromatographic separations on diethylaminoethyl-Sephadex, gel chromatography, and two different electrophoretic procedures. The highly purified was homogeneous when subjected to polyacrylamide gel electrophoresis, ultracentrif... |
Heterogeneities of the two ovalbumin glycopeptides, (Man)5(GlcNAc)2Asn and (Man)6(GlcNAc)2Asn, were revealed by borate paper electrophoresis of oligosaccharide alcohols obtained from the glycopeptides by endo-beta-N-acetylglucosaminidase H digestion and NaB3H4 reduction. The structures of the major components of the ol... |
The apoprotein of hog kidney D-amino acid oxidase was reconstituted with 5-deazaflavin adenine dinucleotide (5-deazaFAD) to yield a protein which contains 1.5 mol of 5-deazaFAD/mol of enzyme. The deazaFAD-containing enzyme forms complexes with benzoate, 2-amino benzoate, and 4-aminobenzoate which are both qualitatively... |
NSILA-s (nonsuppressible insulin-like activity, soluble in acid ethanol) is a serum peptide that has insulin-like and growth-promoting activities. We have demonstrated previously that liver plasma membranes possess separate receptors for NSILA-s and insulin and have characterized the insulin receptor in detail. In the ... |
Phosphoenolpyruvate carboxykinase, which has been isolated from chicken liver mitochondria in essentially homogenous form, carries out the irreversible decarboxylation of oxalacetate to pyruvate in the presence of catalytic amounts of GDP or IDP, as well as the reversible decarboxylation of oxalacetate to phosphoenolpy... |
We describe a method for measuring the release of fatty acids from endogenous substrates of human platelet homogenates and membranes. The method depends on the availability of lipids whose fatty acids are odd-chained and therefore suitable as internal reference compounds that, at the time of lipid extraction, can be ad... |
Hemoglobin Deer Lodge is an abnormal human hemoglobin with arginine substituted for histidine at the beta 2 position. X-ray crystallography of normal human hemoglobin has shown that the beta 2 residue is normally part of the binding site for 2,3-diphosphoglycerate. The substitution of arginine for histidine at beta 2 a... |
Treatment of submitochondrial particles (ETP) with trypsin at 0 degrees destroyed NADPH leads to NAD (or 3-acetylpyridine adenine dinucleotide, AcPyAD) transhydrogenase activity. NADH oxidase activity was unaffected; NADPH oxidase and NADH leads to AcPyAD transhydrogenase activities were diminished by less than 10%. Wh... |
A method is described for the extensive purification of acid deoxyribonuclease (acid DNase) and its specific inhibitor from beef liver, the existence of which had been only supported by indirect evidence. By the use of insolubilized acid deoxyribonuclease, eight other proteins interacting with the enzyme have been dete... |
Nucleotides have at least two functions in eukaryotic cilia and flagella. ATP, originating in the cells, is utilized for motility by energy-transducing protein(s) called dynein, and the binding of guanine nucleotides to tubulin, and probably certain transformations of the bound nucleotides, are prerequisites for the as... |
A sialytransferase activity which catalyzes the synthesis of sialosylgalactosylceramide (G7) from added galactocerebroside and CMP-N-acetylneuraminic acid has been demonstrated in mouse brain microsomes. The enzyme reaction shows a pH optimum of 6.3 and requires detergents. Both Mn2+ and Ca2+ inhibited the reaction, wh... |
We described earlier the facilitated purifications of the trypsin and aminopeptidase components present in Pronase (Vosbeck, K. D., Chow, K. -F., and Awad, W. M., Jr. (1973) J. Biol. Chem. 248, 6029-6034). A partially resolved protein mixture left over after one of the steps in that procedure was passed through a Sepha... |
Location of electron transport chain components in chloroplast membranes of chlamydomonas reinhardi, y-1 was investigated by use of proteolytic digestion with soluble or insolubilized trypsin. Digestion of intact membrane vesicles with soluble trypsin inactivates the water-splitting system, the 3-(3,4-dichlorophenyl)-1... |
The interactions of cytochrome c1 and cytochrome c from bovine cardiac mitochondria were investigated. Cytochrome c1 and cytochrome c formed a 1:1 molecular complex in aqueous solutions of low ionic strength. The complex was stable to Sephadex G-75 chromatography. The formation and stability of the complex were indepen... |
Incubation of leucine aminopeptidase (bovine lens) (EC 3.4.1.1) with various concentrations of Mg2+ at various pH values in 1 M KCl and 0.155 M trimethylamine-HCl at 37 degrees confirms that Mg2+ competes with Zn2+ for binding only 1 site per 54,000-dalton subunit. The ratio of the apparent association constants (1KZn:... |
Large numbers of taste buds are distributed over the body surface of the channel catfish ictalurus punctatus, with the barbels having an especially high density. L-Alanine, as well as certain other amino acids, are taste stimuli in this animal. Epithelial tissue obtained by gentle scraping of the barbel surface was fra... |
Since the coronary veins and capillaries are not involved with arteriosclerotic disease the authors performed experimental, and afterwards, clinical total and selective coronary vein arterialization. Acute myocardial ischaemia created for instance by ligation of the anterior descending branch, was treated by an interna... |
Peroxisome proliferation has been induced with 2-methyl-2-(p-[1,2,3,4-tetrahydro-1-naphthyl]-phenoxy)-propionic acid (Su-13437). DNA, protein, cytochrome oxidase, glucose-6-phosphatase, and acid phosphatase concentrations remain almost constant. Peroxisomal enzyme activities change to approximately 165%, 50%, 30%, and ... |
The ultrastructural localization of NADH oxidase, a possible enzyme in the increased oxidative activity of polymorphonuclear leukocytes (PMN) during phagocytosis, was studied. A new cytochemical technique for the localization of H2O2, a product of NADH oxidase activity, was developed. Cerous ions, in the presence of pe... |
The beige mouse is an animal model for the human Chediak-Higashi syndrome, a disease characterized by giant lysosomes in most cell types. In mice, treatment with androgenic hormones causes a 20-50-fold elevation in at least one kidney lysosomal enzyme, beta-glucuronidase. Beige mice treated with androgen had significan... |
Recently we demonstrated that ethidium bromide altered the plasma and subcellular membrane glycoproteins in control and virus transformed cells. It is reported here that ethidium bromide also stimulated the membrane associated process of sugar transport. The KM of the virus transformed cells and the ethidium bromide tr... |
Catecholamines produce mitotic inhibition in primary cell cultures of human keratinocytes probably via a block in the G2 part of the cell cycle. Epinephrine produced significant mitotic inhibition (49%) at a concentration as low as 4.5 X 10(-10) M, while its analog, isoproterenol, produced 47% inhibition at 1 X 10(-10)... |
HTC cells have been made to grow in chemically defined medium without any macromolecular supplements whatsoever. Initial estimates of their relative amino acid requirements have been made. The cells grown in the defined medium retain many of the differentiated features which have been the focus of investigation in thei... |
Lactic acid production by chick embryo fibroblasts occurs in the absence of exogenous glucose. Fifteen to 50-fold less lactic acid is formed in the absence of glucose than in its presence. Nevertheless, serum and pH stimulation enhances this residual lactic acid production to the same relative extent as when glucose is... |
Granules were isolated from the cytoplasm of the amebocytes of Limulus polyphemus, the horseshoe crab, by disruption of cells obtained from blood which had been drawn into 2 mM propranolol. The granules subsequently were purified by centrifugation through a sucrose gradient that contained heparin. Extracts of the granu... |
Human glucose 6-phosphate dehydrogenase associated with NADPH was efficiently bound with agarose-bound NADP, whereas the enzyme associated with NADP was poorly bound with agarose-bound NADP. After the elimination of haemoglobin from haemolyzate by treatment with DEAE-cellulose, the enzyme was converted into the NADPH-b... |
A quantitative method for the simultaneous determination of propranolol and its active metabolite 4-hydroxypropranolol in human plasma is described. Plasma samples are extracted at pH 9.6 with ethyl acetate after the addition of sodium bisulphite and the internal standard oxprenolol. The extracts are derivatized with t... |
Delta9-and-delta8-Tetrahydrocannabinol, delta9-tetrahydrocannabinolic acid, cannabidiol, cannabidolic acid, cannabinol, cannabinolic acid, cannabichromene and cannabichromenic acid were located in the liquid chromatogram of cannabis. Identifications were confirmed by gas chromatography-mass spectrometry. |
The separation of amino acids has been achieved on a short column of Chromo-Beads C2 resin, with a lithium gradient-elution system. The analysis took 8 h. The separation of asparagine and glutamine from glutamic acid was highly dependent on the sample pH and on the methanol concentration in the first buffer of the grad... |
A gas chromatographic method is described for assay of 3-(5-tetrazolyl) thioxanthone 10,10-dioxide (BW 59C) in human plasma, urine and faeces. After extraction into 1,2-dichloroethane from alkaline medium the compound is converted to the heptafluorobutyrate derivative which is injected into a gas chromatograph and meas... |
Simple methods to enhance the detection of pneumococci in respiratory secretions are needed. Sheep blood agar containing 5 mug of gentamicin per ml was more often positive (89%) than either standard sheep blood agar (54%) or mouse inoculation (65%) in recovering pneumococci from 62 adult and pediatric patients. In adul... |
The dose dependence of the acute effects of ethanol upon liver intermediary metabolism in vivo has been demonstrated in rats. Ethanol was given i.p. in doses of 0.69, 1.7, and 3.0 g/kg in equal volumes (20 ml/kg). The liver was freeze-clamped 120 min after injection, and multiple metabolites were measured in the perchl... |
The solubility of triclinic calcium pyrophosphate dihydrate (CPPD) crystals was measured under varying conditions using 45Ca-labeled crystals, expressing solubility as micromoles per liter of 45Ca in solution. In a 0.1-M Tris-HC1 buffer pH 7.4, the solubility of accurately sized CPPD crystals (37-20mum) was 60muM with ... |
It is proposed that the direct analgesic effect of morphine becomes attenuated over the course of successive administrations of the narcotic by a conditioned, compensatory, hyperalgesic response elicited by the administration procedure, the net result being analgesic tolerance. Using the "hot plate" analgesia assessmen... |
The determination with murexide of free and protein-bound calcium in model systems of known composition, ionic strength, and pH was investigated. The spectra of calcium murexide in the presence of varying amounts of calcium ions indicated that the absorption maximum fo calcium murexide complex occurs at 480 nm while th... |
Lorazepam (0.5, 1, 2, and 4 mg) was compared with pentobarbital (60 and 180 mg) for its effect on sleep in "hospital insomnia." Subjective-response data were collected by research nurses. Lorazepam was found to be a potent nighttime sedative: 1 to 1.25 mg of lorazepam is equivalent to 100 mg sodium pentobarbital for me... |
The effect of low levels of strontium, boron, lithium, molybdenum, and fluorine, alone and in combination, on hydroxyapatite solubility, bacterial growth, and acid production in five antigenic types of Streptococcus mutans was investigated. Pour plates containing synthetic hydroxyapatite were used to compare dissolutio... |
The authors, with 67 Gallium, have obtained positive scintigraphy of the breast only in cases of carcinoma. Reliability of negative scintigraphy however is less good. Isotopic investigation of the bones is important in breast cancer and reveal early osseous metastasis. |
The relationship of enzymatic activity to organelle development and organelle number during differentiation of the metanephric kidney in the mouse was approached from several experimental directions. Biochemical analyses of marker enzymes for peroxisomes (catalase and D-amino acid oxidase), mitochondria (cytochrome oxi... |
The bone marrow reactions (that is, decrease of nucleated cell counts and increase of red blood cell counts) of mouse bone were observed 1 hr after injection of endotoxin and peaked after 18 hr. These reactions were significantly inhibited when diphenhydramine, promethazine (antihistamines), chlorpromazine (antiseroton... |
The interactions between pancreatic lipase and colipase and the substrate and the effect of bile salts on these interactions have been investigated by the use of kinetic experiments and studies on the semiquantitative phase distribution of lipase and colipase activities. The results suggest that lipase binds to hydroph... |
When plasma proteins are diluted with buffer the ionic strength and ionic composition of that buffer affects the interactions between thyroxine (T4) and its plasma protein-binding sites. Increases in phosphate, chloride or barbiturate ion concentration from 50 to 200 mmol/l caused a significant decrease in the affinity... |
1. Using the Falck-Hillarp histochemical technique for monoamines, evidence was found for the presence of a catecholamine in the salivary gland nerves of the moth, Manduca sexta. 2. The innervation was studied with the electron microscope. Only the fluid-secreting region of the gland is innervated and the nerve endings... |
1. Electrophysiological techniques have been employed to examine the nature of the response observed in the ectodermal slow-conduction system (SSI) when dissolved food substances contact the column of Tealia felina. The response seems to consist entirely of sensory activity which may continue for periods of many minute... |
Histamine diphosphate was shown to selectively attract human eosinophils from mixed granulocyte populations when over 20% eosinophils were used in a modified Boyden chamber chemotactic assay system. This effect of histamine is abolished by incubation with diamine oxidase (histaminase) and was generated by decarboxylati... |
Comparative studies of protein structure and function can be quite interesting by themselves, and even more interesting when interpreted with respect to an animal's physiology. In the case of fish hemoglobins, some success in the latter has been achieved but there are still many unsolved problems. It appears that compa... |
This paper reviews the history of understanding how biological systems can discriminate so strikingly among physically similar ions, especially alkali cations. Appreciation of qualitative regularities ("permitted sequences") and quantitative regularities ("selectivity isotherms") in ion selectivity grew first from stud... |
Visual photoreceptors from both vertebrates and invertebrates are characterized by extensive elaboration of membrane which contains visual pigment (rhodopsin). Visual pigments in all phyla examined are chemically similar: the chromophore is 11-cis retinaldehyde attached by an aldimine linkage (Schiff base) to a membran... |
A technique utilizing Pregnant Mare's Serum Gonadotropin and Human Chorionic Gonadotropin treatment of hens (Gallus domesticus), followed by manual ovulation of the excised follicles, was developed to obtain a large number of mature ova. The intact ova were used to test whether acrosin, partially purified from the sper... |
In order to test the range of pH values over which the titratable carried model for inorganic anion exchange is valid, chloride self-exchange across human red blood cells was examined between pH 4.75 and 5.7 at 0 decrees c. It was found that chloride self-exchange flux had a minimum near pH 5 and increased again with f... |
The acetylcholine reversal potential (Er) of cultured rat myotubes is -3mV. When activated, the receptor is permeable to K+ and Na+, but not to Cl- ions. Measurement of Er in Tris+-substituted, Na-free medium also indicated a permeability to Tris+ ions. Unlike adult frog muscle the magnitude of Er was insensitive to ch... |
Cross-reinnvervation of fast (extensor digitorum longus) and slow (soleus) twitch muscles of the rabbit showed essentially complete fast to slow and slow to fast conversion, respectively, 11-12 mo after surgery with respect to a number of physiological parameters including intrinsic shortening, velocity, and isometric ... |
Chitin synthase of Mortierella vinacea was present in the "microsomal' fraction (100 000 g precipitate), the 'cell-wall' fraction (2000 g precipitate) and the 'mitochondrial' fraction (10 000 g precipitate). The properties of the 'microsomal' enzyme were investigated. The pH optimum was between 5-8 and 6-2, and the tem... |
A new method is described for the efficient conversion of Schizosaccharomyces pombe cells into protoplasts. The following parameters of guanine uptake determined in whole cells were unchanged in protoplasts: Km value, requirement for an energy source, sensitivity to competitive inhibitors, pH optimum, as well as the ty... |
When yeast cells were incubated for 4 to 8 h in yeast extract-peptone-glucose medium, pH 6, containing 8 mM-manganese, and then plated on selective media, there was a strong induction of antibiotic-resistant mutations. Indirect evidence suggests that practically all resistant mutants selected were of independent origin... |
An intracellular L-asparaginase with antitumour activity was purified from a strain of Citrobacter. The optimum conditions for enzyme production by fermentation on scales up to 2700 l were investigated. Highest enzyme yield was obtained in corn-steep liquor medium (9-2%, W/V) at 37 degrees C. Oxygen limitation was not ... |
Some mutants and stock strains of Escherichia coli K12 were sensitive to acriflavine in the presence of inorganic phosphate but were resistant to acriflavine in its absence. They mutated spontaneously to resistance to acriflavine plus phosphate. The synergistic effect of phosphate on acriflavine sensitivity was increas... |
The oxidation of carbon monoxide and methane by suspensions and ultrasonic extracts of Pseudomonas methanica was studied. A continuous assay for the oxidation of CO to CO2 was devised, using O2 and CO2 electrodes in combination. Stoicheiometries of CO-dependent CO2 formation, O2 consumption and NADH oxidation, and the ... |
A modified version of systematic desensitization was used to reduce the anxiety and negative interpersonal consequences produced by a recurrent aversive dream resulting from events in the real world. The subject, a 16-year-old incarcerated male, was first taught a standard relaxation technique. The subject's dream was ... |
Arteriograms of the basilar artery reveal that dopamine given intracisternally to dogs can generate cerebral vasospasm. This finding supports a recent hypothesis of others that dopamine may play a role in the pathogenesis of vasospasm, especially since many substances are known which fail to produce such spasm. Compare... |
This study was designed to measure the response of key enzymes of ketone body metabolism in heart, skeletal muscle, and liver to diet and exercise, two conditions known to influence ketone body utilization. A 3 (diet: control, high fat, or high carbohydrate) X 2 (kill condition: rested or exhausted) X 2 (training: trai... |
The levels of plasma carotenoids were markedly reduced in broiler cockerels infected with Eimeria acervulina or E. tenella. The mechanisms of this depigmentation differed between the two species, being primarily associated with interference of absorption of xanthophyll (carotenoids) from the intestinal lumen with E. ac... |
Mechanisms involved in the development of the alcoholic fatty liver in KK-Ay mice were investigated. Incorporation studies using [14C]acetate and [3H]palmitate indicated that the half-life of hepatic triglycerides was doubled in the ethanol-ingesting mice, and utilization of the exogenous fat was significantly increase... |
Response of the fetal kidney to metabolic acidosis was studied in five fetal lambs, 115-125 days gestation, in order to evaluate the renal contribution to elimination of hydrogen ion during intra-uterine development. Experiments were conducted on healthy unanesthetized fetuses, intact in utero, with catheters implanted... |
FHR monitoring and microanalysis of fetal blood are mutually complementary procedures, and optimal knowledge of the fetal state is achieved by making use of both, the former for the preliminary screening of all cases at risk and the latter for the purpose of deciding on obstetric management where pathological changes a... |
Kinetic studies were carried out on the ring opening of the quaternary nitrogen cation, coralynium ion (I), to yield 6'-acetylpapaverine (III), on the cyclization of III to yield I, and on a photochemical reaction undergone by I in aqueous solutions exposed to visible light. From the results, it was concluded that: (a)... |
Hydrolysis of mazindol to form 2-(2-aminoethyl)-3-(p-chlorophenyl)-3-hydroxyphthalimidine was followed spectro-photometrically in aqueous solutions at temperatures between 37 and 70degree, pH values up to 7.6, and an ionic strength of 0.2. The effects of acetate, formate, and phosphate buffers as well as ionic strength... |
The apparent solubility of hexamethylmelamine in aqueous solutions suitable for intravenous use was increased by complexation with gentisic acid. Studies were carried out in the pH 0-8 range. Unprotonated hexamethylmelamine did not form complexes with the gentisate ion, while the hexamethylmelammonium ion appeared to f... |
The inhibitory effect of dioctyl sodium sulfosuccinate on the proteolytic activity of trypsin was investigate over the pH 6-8 range. The antitryptic activity was determined using two different substrates: casein and N,alpha-benzoyl-DL-arginine-p-nitroanilide hydrochloride. The mechanistic studies revealed the substrate... |
The adsorption of diphenoxylate hydrochloride, a potent antidiarrheal agent, on activated charcoal powder was studied in vitro. Langmuir adsorption isotherms were established at pH 4 and 7, and the maximum adsorption capacity of charcoal for this drug was estimated using these values. Activated charcoal modified the bi... |
The binding of bile salts to cholestyramine was studied under varying conditions of pH and added electrolyte. The taurine-conjugated bile salts were strongly absorbed by the anion-exchange resin at low pH and in the presence of chloride anions. Glycocholic acid binding was very weak at low pH but increased strongly wit... |
[14C]amodiaquin accumulation by washed erythrocyte preparations was characterized to permit comparisons with chloroquine accumulation. Erythrocytes infected with Plasmodium berghei CS (chloroquine-susceptible) accumulate amodiaquin by a saturable process that has an apparent dissociation constant for amodiaquin of 7.6 ... |
Post-mortem brain material from control and Parkinson's disease patients was examined to elucidate further the neurochemistry of this disease and to determine the mechanism of action of L-dopa as a therapeutic agent. The activities of L-aromatic amino acid decarboxylase (dopa D), tyrosine hydroxylase, monoamine oxidase... |
These experiments were designed to study the mechanism of depletion of dopamine (DA) in the striatum produced by alpha-methyl-m-tyrosine (alpha-MMT). alpha-Methyl-m-tyramine (alpha-MMTA), the metabolite of alpha-MMT, appears to be the active DA-depleting agent, since the administration of a decarboxylase inhibitor befo... |
1. Gastric acid responses to the test meals were measured in the Heidenhain pouch, gastric and pancreatic fistula dogs, using the intragastric titration method, and monitoring the rate at which a solution of 1-0 N-NaOH had to be added to maintain the pH of the gastric content constant at pre-selected values ranging fro... |
1. The experiments were done on single nodes of Ranvier of Rana esculenta. The effects of tetrodotoxin and H ions were determined either by the reduction of the maximum rate of rise, VA, of action potentials evoked with threshold stimuli or in the voltage clamp by the decrease of the peak Na permeability, PNa. 2. With ... |
1. The experiments were done on single myelinated nerve fibres of Rana esculenta. The rates of toxin effect were studied either by measuring the maximum rate of rise, VA, of repetitively evoked action potentials or by measuring Na currents during periodic impulses in the voltage clamp. 2. VA measurements showed that in... |
1. A study has been made of the formation of synapses in developing reinnervated and cross-reinnervated amphibian twitch muscles which receive either a focal (iliofibularis) or a distributed (sartorius) innervation from 'en plaque' nerve terminals using histological, ultrastructural and electrophysiological techniques.... |
In diphasic blood agar media Trypanosoma vespertilionis developed spheroid clusters as compared to rather long, sausage-shaped (sometimes branched) clusters formed by Trypanosoma dionisii. The former species attained a greater population density (approximately 6 X 10(7) organisms/ml) than the latter (approximately 2 X ... |
All the psychotropic tablets prescribed by a general practitioner in one year are itemised. The patients who received them are separated into diagnostic groups and their treatment is analysed by the number of attendances, prescriptions, and duration of therapy. Hospital referrals and overdoses over a longer period are ... |
Secondary and tertiary amino homologs of the title compounds have been prepared, bearing an N-isopropyl group. In peripheral evaluation, certain members of the series exhibited beta-adrenergic agonist effects of lower activity than isoproterenol. N-Methyl-N-isopropyl-5,6-dihydroxytetralin exhibited marked properties co... |
Apparent values of Km and Vmax have been measured for catalysis of hydrolysis of unsonicated egg lecithin liposomes, activated through addition of 0.4 M n-hexanol, by phospholipases A2 from bee and snake venoms and by phospholipase C from Clostridium welchii as a function of the concentration of three surfactants: hexa... |
The isolated skin of the toad Bufo marinus ictericus when impaled from the outer surface by glass microelectrodes filled with 3 M KCl shows a voltage profile which is a continuous function of the depth of impalement. The superficial intraepithelial potential difference measured with reference to the external solution (... |
The quality of ultrastructural preservation of the avian erythrocyte achieved using various fixation techniques is evaluated. Different combinations of initial fixatives, buffers and post-fixation procedures were tested as well as variations in fixative osmolarity, pH and temperature. Of the commonly used initial fixat... |
1) A study was carried out to determine the oxyhemoglobin dissociation curve of stroma-free hemoglobin solution and factors which influence it, (pH; 2,3 DPG). 2) To simulate acute volume replacement, dilution experiments, in vitro, were performed employing both hemoglobin solution and Ringer's lactate in whole blood. 3... |
Tiny (0.2% TBS), partial thickness, non-contact radiant heat burns in guinea pigs resulted, within 3 hours, in significant edema formation and protein leakage at the site of the injury. Areas of skin distant to the burn also showed an increase in water content but no protein leakage. Pretreatment of the animals with ei... |
The location of T4D phage-induced dihydrofolate reductase (dfr) has been determined in intact and incomplete phage particles. It has been found that phage mutants inducing a temperature-sensitive dfr (dfrts) procude heat-labile phage particles. The structural dfr produced by these ts mutants was shown to assume differe... |
An RNA-dependent RNA polymerase activity has been found associated with Uukuniemi virions. The enzyme activity is expressed only after disrupting the virions with the nonionic detergent Triton X-100 and is absolutely dependent on Mn2+, whereas Mg2+ is not required, a finding that distinguishes this polymerase from thos... |
Dental anomalies were observed in 43 of 1,226 barren-ground caribou (Rangifer tarandus groenlandicus) taken between 1966 and 1968. In five of these 43 animals, the mandibles had deformities which radiography showed to be the result of dental abscesses in four cases and probably of a trauma in the other. The absence of ... |
Purified C. perfringens type A enterotoxin fed orally in an amount of 5 mg caused both vomiting and diarrhea in the monkey only when the gastric juice had been neutralized. Exposure of enterotoxin to pH 4.0 or below rapidly destroyed the activity. All three monkeys receiving sodium bicarbonate and 2.4 X 10(10) viable c... |
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