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1.
Summary Axillary 5-androst-16-en-3-one (5-androstenone) levels were found to be significantly higher in men than in women but do not vary between left and right axillae, are not related to age, handedness or degree of hirsutism (in women) nor to anosmia to this steroid. In men (but not in women), levels are related linearly to axillary cholesterol concentrations but not to squalene. Olfactory thresholds for 5-androstenone varied widely, the lowest recorded being 0.2 ppb, but there was no difference in thresholds between men and women. Women (70%) found the smell repellant but anosmia did not differ greatly between men and women (9–20%). Anosmia to the smell of 5-androst-16-en-3-ol was most marked in women (90%) rather than in men (45%). Axillary 5-androstenone values were generally consistent with the musky or strong smells of male axillary extracts, compared with the sweet smell of those from female subjects.Supported by the Herbert Dunhill Trust.  相似文献   

2.
Differences in the tissue content of prothymosin during the early postnatal development of male and female rats are reported. Thymus and spleen have been found to contain significantly higher amounts of prothymosin in the newborn and prepubertal animals, as compared to adults, whereas liver has been found to contain low levels of prothymosin throughout development. These findings indicate a functional association of prothymosin with the proliferating lymphoid tissues of the young rat.  相似文献   

3.
Summary The levels of rat plasma -macroglobulins, -cysteine proteinase inhibitor, haptoglobin and antipapain activity were studied during the acute-phase reaction after an injection of -pinen. An increase in concentration of all the compounds examined was observed.  相似文献   

4.
Summary Enzymatic hydrolysis of several racemic N-phenylacetyl--methyl--amino acids containing an additinal aliphatic, aromatic or polar substitutent on the chiral carbon atom, has been studied by using benzylpenicillincylase fromEscherichia coli A.T.C.C. 9637. Both the rate of hydrolysis and the stereoselectivity were found to be considerably lower than in the case of natural -amino acids. Steric and electronic factors in the side chains influencing the stereoselectivity are discussed.  相似文献   

5.
Summary We have determined that the porcine thyroidal TSH receptor is a glycoprotein heterotetramer composed of two Mr 35,000 () covalently linked subunits which interact noncovalently with two copies of (Mr 66,000) chains.Acknowledgments. This work was supported by grants from the Medical Research Council of Canada.  相似文献   

6.
Summary Ascorbic acid and glutathione concentrations increase in brown fat of cold-exposed rats. This phenomenon can be reproduced by noradrenaline or isoproterenol administration, and thus seems to be under sympathetic control. Histological study shows ascorbic acid storage in brown adipocyte nuclei.  相似文献   

7.
Information on the bioactivities of non-mammalian cytokines is scant due to the lack of the recombinant molecules and specific antibodies. We produced the mature predicted peptide of tumor necrosis factor (TNF) from the bony fish gilthead seabream (Sparus aurata L.) (sbTNF), and its biological role was determined in vitro and in vivo. We first demonstrated by analytical size-exclusion chromatography that sbTNF is an oligomeric protein but the dimer appears to predominate over the trimeric form, in contrast to mammalian TNF. Intraperitoneal injection of native sbTNF resulted in (i) priming of the respiratory burst of the peritoneal exudate and head-kidney (HK) leukocytes, the latter being the bone marrow equivalent in fish; (ii) rapid recruitment of phagocytic granulocytes to the injection site, and (iii) induction of granulopoiesis in the HK. Interestingly, sbTNF was able to induce a strong proliferation of HK cells in vitro, whereas human TNF did not. Conversely, sbTNF was not cytotoxic for murine L929 fibroblasts.Received 12 February 2004; received after revision 15 March 2004; accepted 29 March 2004  相似文献   

8.
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10.
Summary A sensitive radioimmunoassay showed that circulating -interferon in the plasma of healthy individuals was low in children and reached the highest level in the young adult, then declined gradually with age. Circulating -interferon was 0.201±0.059 ng/ml in males (n=19) and 0.184±0.076 ng/ml in females (n=14) at ages 30–39 years old. It was noted that circulating -interferon was maintained up to a certain level even in elderly individuals.  相似文献   

11.
Summary In the normal Wistar rat, the plasma -MSH level was raised by hypertonic saline injection (as compared with control rats injected with isotonic saline). No such rise in -MSH followed hypertonic saline administration in the Brattleboro (hereditary diabetes insipidus) animal (compared to isotonic saline injected controls). It is suggested that, in the rat, endogenous antidiuretic hormone is involved in the secretory response of the pars intermedia to osmotic stimuli.  相似文献   

12.
Summary Removal of the ventral prostate gland in adult male rats causes an increase in adrenal weight, and stimulation of adrenal 5-3-hydroxysteroid dehydrogenase activity along with elevation of serum levels of corticosterone and prolactin.  相似文献   

13.
Angiogenesis activation mediated by vascular endothelial growth factor (VEGF) is one of the factors that can cause antiestrogen treatment failure in estrogen receptor (ER)?positive breast cancer patients. Since VEGF synthesis is modulated not only by hypoxia but also by steroid hormones, we investigated the relationship between hypoxic and estrogenic/antiestrogenic stimuli in two human breast cancer cell lines expressing both ER6α and ERβ (MCF7) or only ERβ (MDA-MB231). In both cell lines, the VEGF level was significantly influenced by hypoxic conditions and in antiestrogen-responsive MCF7 cells, this effect was not counteracted by tamoxifen or ICI 182,780, thus providing an experimental explanation for the resistance to endocrine treatment observed in patients with ER-positive tumors. In MDA-MB231 cells, estradiol significantly reduced the VEGF level, suggesting that through the ERβ isoform it may function as a negative modulator of VEGF synthesis under hypoxia, and providing evidence for a complex interplay of the estrogen-dependent and hypoxia-dependent pathways.  相似文献   

14.
Summary In the rabbit isolated aorta, hymenin (10–6 M) a novel marine alkaloid, caused a parallel rightward shift of the dose-response curve for norepinephrine without affecting that for histamine or KCl, suggesting that hymenin is a competitive antagonist of -adrenoceptors in vascular smooth muscles.Acknowledgments. We thank Ms A. Kajiwara and Ms M. Hamashima of this institute for their technical assistance, and Prof. Y. Hirata of Meijo University for his encouragement.  相似文献   

15.
Summary Two components of the venom of the predatory waspPhilanthus triangulum F. significantly reduce — to a greater or less extent — the high affinity uptake of glutamate in rat hippocampus. A concentration of 10 M -PTX caused a reduction of 74%, while the other component, -PTX, at the same concentration, caused a reduction of 18%. Hence the effect of -PTX on high affinity glutamate uptake in the hippocampus is comparable with its effect on high affinity glutamate uptake in insect neuromuscular junctions. Contrary to our previous findings that -PTX has no effect on high affinity glutamate uptake in insect glutamatergic terminal axons, however, -PTX significantly reduces high affinity glutamate uptake in the hippocampus, albeit less effectively than -PTX.  相似文献   

16.
Summary -MSH (0.1, 1, 10 g) was administered intracerebroventricularly and its action on pain sensitivity was investigated by the hot-plate method in mice. -MSH produced dose-dependent analgesia and this analgesic effect was prevented by naloxone (1 mg/kg, s.c.). It is possible that -MSH may play a role in the mechanism of pain through endogeneous opioid systems.  相似文献   

17.
Summary Ethanol may modulate endogenous opioid systems by disrupting opioid receptor signalling. Low concentrations of ethanol slightly potentiate -opioid receptor binding by increasing receptor Bmax, and, in some cases, chronic ethanol exposure decreases the density or affinity of the -opioid receptors. By contrast, high concentrations of ethanol acutely decrease -opioid receptor binding by decreasing receptor affinity, whereas chronic exposure of animals and neuronal cell lines to lower concentrations of ethanol leads to possibly adaptive increases in the density or affinity of the -opioid receptors. In the neuronal cell line NG108-15, ethanol does not up-regulate the -opioid receptor by blocking receptor degradation or endocytosis, but protein synthesis is required for this response. Up-regulation of the -opioid receptor renders ethanol-treated NG108-15 cells 3.5-fold more sensitive to opioid inhibition of adenylyl cyclase. Long-term treatment with ethanol also increases maximal opioid inhibition in NG108-15 cells, possibly by decreasing levels of Gs and its mRNA. Ethanol differentially modulates signal transduction proteins in three additional neuronal cell lines, N18TG2, N4TG1, and N1E-115. Ethanol-treated N18TG2 cells show the least up-regulation of the -opioid receptor, little heterologous desensitization of adenylyl cyclase, and no changes in Gs or Gi. By contrast, ethanol-treated N1E-115 cells show the largest up-regulation of the -opioid receptor, the most heterologous desensitization of adenylyl cyclase, and concentration-dependent decreases in Gs and increases in Gi. Further analysis of these related neuronal cell lines may help to identify the molecular elements that endow some, but not all, neuronal cells with the capacity to adapt to ethanol.  相似文献   

18.
Summary Glutathione S-transferase activity in rat intestinal mucosa was increased by the injection of -unsaturated carbonyl compounds such as phorone and diethylmaleate, but that in the liver and kidney was not. Since the administration of cycloheximide completely blocked the increase of the enzyme activity by phorone, the increase of the activity may be due to de novo synthesis rather than enzyme activation.  相似文献   

19.
A new radioimmunoassay has been developed for thymosin 4 by generating rabbit polyclonal antibodies against the synthetic N-terminal peptide fragment 1–15 coupled to KLH. The synthetic analogue [Tyr12]-thymosin 4 (1–15) was used as tracer. This radioimmunoassay, with a useful range of 10–1000 pmoles, showed cross-reactivity with the second homologous -thymosin of man and rat (thymosin 10) but not of calf (thymosin 9). This radioimmunoassay, together with an improved radioimmunoassay for the N-terminus of parathymosin , was employed for the measurement of the levels of thymosin 4 and parathymosin in nuclear and extranuclear extracts of calf thymus. The bulk of these polypeptides was found in the extranuclear material whereas only traces were observed in the nuclear environment, which indicates the extranuclear localisation of - and -thymosins.  相似文献   

20.
Summary We describe here a further Japanese family with pyrimidine 5-nucleotidase (P5N) deficiency diagnosed using a nuclear magnetic resonance (NMR) spectrum, in Kumamoto prefecture where two families having the disease have been reported before. The specific spectra in1H-NMR of P5N deficient erythrocytes were due to three methyl protons of CDP-choline at 3.22 ppm and to H-2, H-8 and ribose-1 of pyrimidine nucleotide phosphate(s) in the lower fields (at 5.82 and 8.00 ppm). The other specificities in31P-NMR spectra were due to CDP-choline, CDP-ethanolamine and UDP-glucose. Those spectra were not detected in other types of hemolytic anemia.  相似文献   

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