Search Results
Results 601 - 650 of 714
< 5 6 7 8 9 10 11 12 13 14 15 >
Keutmann H T - - 1978
During the isolation of human parathyroid hormone there is an extensive loss of immuno-assayble hormone over the successive extraction steps, due in part to the presence of fragments that are soluble in 4% trichloroacetic acid. These fragments are derived from both the amino- and carboxyl-terminal regions of the hormone. The ...
Mariano E C - - 1978
Eight dogs, four with intact vagi and four with vagotomy, were studied to see if the gastric secretory effect of intravenously administered L-amino acids is mediated by a gastrointestinal (GI) hormone or hormones. Intravenous infusion of amino acids produced a significant secretory response in denervated and in innervated stomachs. When ...
Wallis M - - 1978
Rat somatotropin (growth hormone) was labelled biosynthetically by incubating anterior pituitary lobes with radioactive amino acids for 24 h in a simple buffered salts medium containing glucose. The labelled hormone was isolated by preparative polyacrylamide-gel electrophoresis or by chromatography on Sephadex G-100 and then DEAE-cellulose. The labelled material was pure ...
Vignal A - - 1978
The distribution of iodotyrosines and iodothyroinines has been studied in poorly iodinated 19 S thyroglobulins isolated by sucrose gradient centrifugation from five human thyroid tissue. The 19 S thyroglobulins have been fractionated by isopycnic centrifugation and 34.5% rubidium chloride gradient. The distribution of iodoamino acids depends on the total iodine ...
Yonezawa H - - 1978
The decapeptide corresponding to the amino acid sequence of porcine luteinizing hormone-releasing hormone (LH-RH) which involves 1 mol of tryptophan was synthesized via solid phase synthesis with two different deblocking procedures which used hydrogen chloride in formic acid and hydrogen chloride in acetic acid containing 1% 2-mercaptoethanol. After some fundamental ...
Alberti K G - - 1978
The main hormones involved in ketone-body metabolism are the anabolic hormone insulin and the primarily catabolic hormones, glucagon, cortisol, catecholamines and growth hormone. These hormones may regulate ketone-body metabolism at three sites: adipose tissue, by regulating fatty acid supply to the liver; the liver itself, by determining the relative activities ...
Fuhr J E - - 1978
Marmoset reticulocytes and bone marrow provide a valuable tissue resource for the study of primate hemoglobin structure and synthesis. The amino acid sequence of the marmoset hemoglobin has been determined, and the close homology between it and that of the human suggest it may be a valuable model for study ...
Silbermann M - - 1978
Immature female mice were treated with daily doses of triamcinolone diacetate. Using histochemical and fluorescent methods, the mineralization pattern of the proximal epiphyseal plate of the humerus was studied at various intervals. Following 1 injection, a noticeable decrease was noted in the oxytetracycline incorporation at the mineralizing zone of the ...
Naudé R J - - 1977
1. Avian corticotropin (ACTH) was purified from both fresh and aged pituitary glands of the ostrich Struthio camelus. 2. The isolation of corticotropin in pure form involved acid/acetone extraction, NaCl fractionation, CM-cellulose chromatography and Sephadex G-50 chromatography. 3. The hormone preparations from fresh and aged glands behaved as single substances ...
Visser T J - - 1977
Radioimmunoassays for the measurement of the 1--34 human parathyroid hormone fragment (1--34 hPTH) were developed using antisera raised in rabbits against synthetic 1--34 hPTH-N (amino acid sequence proposed by Niall). Binding of 125I-labelled 1--34 hPTH-N to these antisera was optimal at pH 5-5. Limits of detection varied between 25 and ...
Gerulath A H - - 1977
Nucleic acid synthesis was studied in 26 tumor specimens, during a one-hour in vitro incubation with the addition of progesterone and estradiol-17beta. On the response scale used, deoxyribonucleic acid and ribonucleic acid synthesis decreased linearly as the logarithmic concentration of either hormone increased. Inhibition of nucleic acid synthesis was highly ...
Kanke Y - - 1977
Male mice were treated with 10 microng of oestradiol for 5 days in order to study the effect of the hormone on both the distribution and the rate of synthesis of glycosaminoglycans and glycoproteins in the skin. Oestradiol exerts a very specific effect on glycosaminoglycans by increasing hyaluronic acid concentration ...
Harvey S - - 1977
Chicken growth hormone has been isolated from adenohypophysial tissue from which the glycoprotein hormones had been removed. The procedure entailed alkali extraction, ammonium sulphate precipitation and ion-exchange chromatography on DEAE-cellulose. The resulting fraction was homogeneous, active in the rat tibia bioassay and had a similar isoelectric point, molecular weight and ...
Tamura-Takahashi H - - 1977
Four biologically active components of luteinizing hormone (LH), designated as LH I, II, III, and IV, were isolated from whale pituitary glands. These components migrated as single bands with different mobilities in disc electrophoresis, and their isoeletric points were at pH 8.1, 8.3, 8.5, and 8.7, respectively. Their amino acid ...
Ammirato P V - - 1977
The effects of abscisic acid, zeatin, and gibberellic acid on the development of somatic embryos from cultured cells of caraway (Carum carvi L.) were observed.Somatic embryos complete development on a basal medium without exogenous hormones, but some are subject to developmental abnormalities including malformed cotyledons and accessory embryos. Both zeatin ...
Pollard J W - - 1977
Newly synthesized non-histone proteins (NHP) labelled with [35S] methionine were isolated from uterine epithelium and stroma after different hormone treatments and examined by isoelectric focusing in polyacrylamide gels. Progesterone increased the proportion of basic NHP in the epithelium. This effect was detectable within 4 h and was maintained unchanged after ...
Malejka-Giganti D - - 1977
This work confirms the previous observation that a single application of N-hydroxy-2-fluorenylacetamide or N-hydroxy-3-fluorenylacetamide to the mammary gland of the rat induced a high incidence of tumors, whereas the corresponding arylamides, N-2-fluorenylacetamide (2-FAA) and N-3-fluorenylacetamide, were only weakly active. The results suggested N-hydroxylation of the arylamides as a prerequisite for ...
Marche P - - 1976
The luminescence properties (fluorescence and phosphorescence) of luliberin have been investigated at liquid-nitrogen temperature (77 K) in 50% ethylene glycolaqueous buffer at various pH's. Calculation of the energy-transfer efficiency between Trp and Tyr residues leads to an evaluation of the distance separating these residues. In alkaline medium, when tyrosine is ...
Chang T M - - 1976
Semipermeable microcapsules were prepared using biodegradable material as the enclosing membranes. For instance, polylactic acid was used as membrane material to microencapsulate biologically active materials. Asparaginase microencapsulated within polylactic acids functions effectively in converting external asparagine into aspartic acid and ammonium. By variations in permeability characteristics, insulin microencapsulated within polylactic ...
Li C H - - 1976
The recombinant hormone obtained by non-covalent interaction of the NH2-terminal 134 amino acid fragment with the COOH-terminal 51 amino acid fragment of the reduced-carbamidomethylated human somatotropin molecule is found to exhibit nearly full biological activity of the native hormone, as evidenced by the stimulation of hepatic ornithine decarboxylase (L-ornithine carboxy-lyase, ...
Walter R - - 1976
In a continued effort to relate the three-dimensional structure of a peptide hormone to its biological activity, the dose-response relationships of [3-phenylalanine] oxytocin (oxypressin), with an aromatic amino acid residue in position 3, and [3-beta-cyclohexylalanine]oxytocin, with an aliphatic amino acid residue to position 3, were determined in the rat uterine ...
Wildenthal K - - 1976
Prolonged starvation is known to induce significant alterations in several cardiac lysosomal enzymes, particularly the acid proteinase cathepsin D. To determine what specific factors might mediate these changes, fetal mouse hearts in organ culture were maintained in media designed to simulate selected hormonal or nutritional substrate changes that accompany starvation. ...
Martínez-Honduvilla C J - - 1976
The effects of exogenous growth factors (indolacetic acid, gibberellic acid and kinetin and steroidal hormones (estrone, estradiol and testosterone on the germination pattern of Pinus pinea seeds were studied. Nucleic acids metabolism during the stages before germination, has also been investigated. Seeds sown in the presence of all these substances, ...
Quamme G A - - 1976
Previous studies have indicated the existence of natriuretic factors of hormonal nature with the posterior pituitary gland as a possible site of origin. It was in this light that a series of experiments was designed to examine the posterior pituitary for such factors. Acetic acid extracts of porcine and bovine ...
Habener J F - - 1976
Pre-proparathyroid hormone, discovered previously by the translation of messenger RNA from parathyroid glands in heterologous cell-free systems, is a polypeptide of 115 amino acids consisting of 25 amino acids added to the NH2 terminus of proparathyroid hormone (90 amino acids), the immediate biosynthetic precursor of parathyroid hormone (84 amino acids). ...
Smith G - - 1976
A new peptide having both lipolytic and melanotropic properties has been isolated from human pituitary glands. It has a molecular weight around 11,000, an amino acid composition different from the known lipolytic-melanotropic hormones, and an isoelectric point of 8.5. Although it is not entirely pure, there is no doubt that ...
Li C H - - 1976
The NH2-terminal 134 amino-acid fragment of the reduced-carbamidomethylated human somatropin molecule is found to react noncovalently with the COOH-terminal 51 amino-acid fragment in solutions of pH 8.4 at 2 degrees to restore full biological activity as evidenced by the rat tibia and pigeon crop-sac assays. In addition, circular dichroism spectra ...
Alvim R - - 1976
Changes in levels of abscisic acid (ABA) and cytokinin activity in the xylem sap of willow (Salix viminalis, L.) were followed throughout two growth cycles.Growth in spring was preceded by decreasing levels of ABA and an increase in cytokinin activity. The onset of dormancy was associated with low levels of ...
Kondo Y - - 1976
The sonicate of microsomal fraction of hog thyroid was found to contain two species of proteins which reacted with anti-thyroglobulin antiserum and corresponded to 2 to 3% of total protein of the fraction. The two species were purified by ammonium sulfate precipitation, repeated sucrose density gradient centrifugations and separated from ...
Jacobs M M - - 1976
Porcine follicle-stimulating hormone (pFSH) has been prepared from acetone dried pituitary glands. The acetone powder was initially extracted in pH 5 ethanol-acetate buffer (40% ethanol and acetate at 0.5 ionic strength) containing 0.02% PMSF. The gonadotropin rich fraction, obtained in the 80% ethanol precipitate, was dissolved in 0.12 M NH4HCO3, ...
Baker B I - - 1976
Various agents were tested for their ability to oppose the stimulatory effect of dibutyryl cyclic AMP on the release of the melanocyte-stimulating hormone from the rat neuro intermediate lobe in vitro. Only dopamine exhibited an inhibitory effect; serotonin, gamma-amino-butyric acid, tocinoic acid, tocinamide, the tripeptide Pro-Leu-Gly-NH2 and dibutyryl cyclic GMP ...
Reaven G M - - 1976
Hypercalcemia, which occurs 4 hr after bilateral nephrectomy in normal rats, is not seen 4 hr after either bilateral ureterotomy or sham surgery. These results indicate that it is loss of renal mass per se, not the uremic syndrome, which is responsible for the hypercalcemia. Citric acid levels also increase ...
Kemper B - - 1976
The amino acid sequence of bovine pre-proparathyroid hormone has been partially determined by analysis of the polypeptide labeled selectively with radioactive amino acids. Analysis of tryptic peptides containing methionine or lysine indicated that parathyroid hormone, proparathyroid hormone, and pre-proparathyroid hormone had several common peptides. Two lysine-containing peptides present in proparathyroid ...
Faerch T - - 1976
The use of [125I] thyroxine in the determination of dialysable thyroxine (free T4) places very high demands on the purity of the reagent. Less than 5% dissociated radioactive iodine (as iodide) is enough to influence the results [1]. For this reason several workers have developed methods for the purification of ...
Mutt V - - 1976
Attempts are described to identify additional polypeptides of hormonal nature in a concentrate of intestinal polypeptides shown previously to contain secretin, cholecystokinin-pancreozymin (CCK), motilin, gastric inhibitory polypeptide (GIP), vasoactive intestinal polypeptide (VIP), enteroglucagon and chymodenin. The probable amino acid sequence of a variant form of CCK is disclosed. The possibility ...
Visser T J - - 1976
The inactivation of the hypothalamic hormone by rat liver and kidney homogenates was studied, using specific radioimmunoassays for the measurement of thyrotropin releasing hormone, pGlu-His-Pro-NH2 (TRH), and for an analogous peptide, pGlu-His-Pro-OH(TRH-OH), which has been proposed as a major metabolite of TRH [NAIR et al., 1971]. The inactivation of TRH ...
Ondo J G - - 1976
Several neurally excitant amino acids were injected into the third ventricle of anesthetized male rats, and plasma levels of luteinizing hormone (LH) and follicle stimulating hormone (FSH) were measured. LH levels increased following injections of 2.0 mum glutamate, lysine, or beta-alanine. Glycine (2.0 mum), alpha-alanine (2.0 mum), and 0.9% saline ...
Bujatti M - - 1976
The highly significant increase of 5-HIAA (5-hydroxyindole-3-acetic acid) in Transcendental Meditation technique suggests systemic serotonin as "rest and fulfillment hormone" of deactivation-relaxation. Furthermore 5-HT (5-hydroxytryptamine, serotonin) is considered to be the EC-cell (enterochromaffine-cell) hormone requested by Fujita and Kobayashi and its role for EEG synchronisation via area postrema chemoreceptor as ...
Ebel H - - 1975
The in vitro effect of various diuretics on rat kidney adenylate cyclase was investigated in crude homogenates of the cortex, the outer and inner medulla. 10-3 M furosemide inhibited adenylate cyclase by 40% in the cortex, by 16% in the outer medulla and by 43% in the inner medulla. 10-3 ...
Beattie C W - - 1975
Ten analogs of luteinizing hormone-releasing hormone (LH-RH) substituted in position 2 with D-amino acids and at 6 with either a D-amino acid or a nonasymmetric amino acid were synthesized by solid-phase methodology and assayed for antiovulatory activity. [D-Phe2]-LH-RH substituted in the 6 position with D-Ala, D-Leu, D-Arg, D-(Ph)Gly, D-Phe, or ...
Adams P A - - 1975
Extensibility characteristics of Avena stem segments treated with gibberellic acid (GA) were investigated in living internodes using a microgrowth method and in partially extracted cell walls subjected to Instron extensometer analysis. Both techniques showed that treatment with GA greatly increases internodal plasticity, but has virtually no effect on internodal elasticity. ...
Ma G Y - - 1975
1. Vasopressin (anti-diuretic hormone, [8-arginine]vasopressin) inhibited the synthesis de novo of fatty acids (measured with (3)H(2)O and U-(14)C-labelled lactate or U-(14)C-labelled glucose) and stimulated glycogen breakdown in the perfused liver of fed mice. 2. The concentration dependence of these effects (range 200-1000muunits/ml, i.e. 0.5-2.5ng/ml) resembled that for the action on ...
Walter R - - 1975
Neurohypophyseal hormones and several of their analogs, as well as N-terminal and C-terminal fragments, have been studied for their ability to attenuate puromycin-induced amnesia in mice. [8-Lysine]vasopressin, [8-arginine]vasopressin, and the analogs des-9-glycinamide-[8-lysine]vasopressin, [1-beta-mercaptopropionic acid, 8-lysine]vasopressin, [1,6-aminosuberic acid, 8-lysine]vasopressin, [4-leucine, 8-lysine]vasopressin, glycyl-glycyl-glycyl-[8-lysine]vasopressin, [1-beta-mercaptopropionic acid, 8-D-arginine]vasopressin, and [1,6-aminosuberic acid, 8-arginine]vasopressin are active. ...
Gee J D - - 1975
The rate of secretion of the Malpighian tubules of Glossina austeni is controlled by a diuretic hormone. This hormone is present in the nervous tissue of the fly together with a degradative enzyme that can be activated by boiling. It is demonstrated that the Malpighian tubules are able to destroy ...
Neuman W F - - 1975
Further studies on the preparation of 125I-labeled, biologically active parathyroid hormone have resulted in improvements in the procedure, in the storage of the labeled product, and in the establisment of the location of the label in the polypeptide chain. Approximately 95% of the label is on the single tyrosyl residue, ...
Diaz-Buxo J A - - 1975
Parathyroid hormone has been recognized as an important factor in the regulation of renal function since the 1920s. Early investigations mainly characterized the role of the hormone in calcium and phosphorus metabolism. Subsequently, significant contributions have been made to the understanding of the influence of parathyroid hormone on acid-base balance ...
Kennedy T G - - 1975
Hypophysectomized-ovariectomized mice receiving oestrogen and progesterone were treated with and without bovine prolactin and growth hormone (GH). Prolactin significantly increased vaginal weight and vaginal sialic acid content, but had no effect on vaginal sialic acid concentration, an indicator of vaginal mucification. Growth hormone significantly increased all three vaginal parameters. For ...
Kjeld J M - - 1975
High specific activity [125-I] triiodothyronine and [125-I] thyroxine have been produced regularly by the chloramine T radioiodination method. Simultaneous production of [125-I] triiodothyronine and [125-I] thyroxine is usual when diiodothyronine or triiodothyronine are employed as the starting materials. Specific activities reached vary with the starting compound (diiodothyronine, triiodothyronine, thyroxine) used, ...
Tobe S S - - 1975
1. Radiochemical in vitro assays show that there are large and rapid changes in the spontaneous rate of juvenile hormone synthesis and release during the course of sexual maturation in the locust. 2. Parallel observations on glands incubated with farnesenic acid show that the rate-limiting step is always prior to ...
Symons C - - 1975
Severe cardiac hypertrophy has been produced experimentally in rats by long-term, low-dose treatment with tri-iodothyroacetic acid. The dose used was insufficient to cause any apparent systemic or metabolic effect. It is suggested that similar iodinated substances in the blood in man, resulting from normal or abnormal thyroid hormone catabolism, may ...
< 5 6 7 8 9 10 11 12 13 14 15 >