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Morphofunctional indices of pyracryl (phosphate poly-2-pyridylethylmethacrilate) effecting reproduction system of Wistar rats have been studied. It has been shown that monthly administration of pyracryl in doses 1 mg/kg and 5 mg/kg lead to infiltration of mast cells and their pronounced degranulation and impairment of blood and lymph microcirculation. As far as gonadotropic effect is concerned, its parametres depend on the administration of pyracryl. Pyracryl in doses of 1 mg/kg stimulates folliculogenesis in ovaries, a dose of 5 mg/kg may cause expressed atresia of growing follicules and changes of oestrous cycle. It is suggested that biologically active substances of mast cells in female reproduction system play an important role in realization of gonadotropic effects of pyracryl.  相似文献   
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This study seeks to explore whether neuroticism, agreeableness, and conscientiousness moderate the influence of relationship conflict experienced in groups on changes in group members'' evaluative cognitions related to teamwork quality (teamwork-related mental models). Data from 216 students, nested in 48 groups were analyzed using a multilevel modeling approach. Our results show that the experience of relationship conflict leads to a negative shift from the pre-task to the post-task teamwork-related mental models. Moreover, the results indicate that conscientiousness buffered the negative association between relationship conflict and the change in teamwork-related mental models. Our results did not support the hypothesized moderating effect of agreeableness and show that the detrimental effect of relationship conflict on the shift in teamwork-related mental models is accentuated for group members scoring low rather than high on neuroticism. These findings open new research venues for exploring the association between personality, coping styles and change in teamwork-related mental models.  相似文献   
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The biomechanical model of human coronary arteries was modified for improving the quality of diagnosis and surgical treatment for coronary heart disease. The problem of hemodynamics in the left coronary artery with multivessel bed disease – 45% stenosis of the anterior descending branch and 75% stenosis of the circumflex branch – was particularly considered. Numerical simulation of the coronary arterial bypass of the main trunk was carried out to estimate the functional condition of the coronary arteries after restoring myocardial blood supply by surgery.  相似文献   
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cGMP markedly increases the cationic conductance of the 'inside-out' patches of rod outer segment plasma membrane when applied to the inner side. The cGMP-activated conductance of some patches was shown to be time-dependent. The data obtained suggest that the change of cGMP concentration in the near membrane layer underlies this phenomenon rather than the change in the channel's activity. The hydrolysis and, probably, the desorption of the nucleotide are responsible for this.  相似文献   
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On the basis of chemical and NMR data the partial structure of lipid A from lipooligosaccharide (LOS) of Neisseria meningitidis group B, strain BC5S No 125 was established. Lipid A consisted of disaccharide 2-deoxy-6-O-[2-deoxy-2-(3-hydroxytetradecanoylamino)--gluco-pyranosyl]-2-(3-hydroxytetradecanoylamino)--glucopyranose carrying the -(2-aminoethyl)pyrophosphate residue at 0–4 and the pyrophosphate or phosphate residue at 0–1. On hydrolysis of the acidic form of LOS with 1% acetic acid the substituent at 0–1 was practically completely removed whereas that at 0–4 was stable. The analogous hydrolysis of the Mg-salt of LOS was accompanied by splitting off the pyrophosphate linkage in the substituent at 0–4. Hydrolysis of LOS at pH 4.5 in the presence of SDS led mainly to a lipid A preparation retaining both pyrophosphate residues.Abbreviations KDO 2-keto-3-deoxyoctulosonic acid - LA-I, LA-II preparations of lipid A - LOS lipooligosaccharide - LOS-H+ the acidic form of LOS - OS oligosaccharide - TLC thin-layer chromatography - GLC-MS gas-liquid chromatography/mass spectrometry  相似文献   
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Properties of odour-binding glycoproteins from rat olfactory epithelium   总被引:2,自引:0,他引:2  
The specific membrane glycoproteins with high affinity for camphor and decanal were isolated from rat olfactory epithelium. Antibodies to these glycoproteins inhibited both the electroolfactogram and the binding of odorants. The enzyme immunoassay has shown these glycoproteins to be present in the olfactory epithelium of rat, mouse, guinea-pig and hamster but not in that of frog and carp. The molecular mass of the odour-binding glycoproteins from rat olfactory epithelium solubilized by Triton X-100 was approx. 140 kDa. They consisted of two subunits (88 and 55 kDa). The 88 kDa subunit was capable of binding odorants. The data obtained suggest that the glycoproteins isolated have some properties that make them plausible candidates for olfactory receptor molecules.  相似文献   
9.
Summary A high-yield microbiological transformation of polyfunctional 5-3-acetoxy steroids, containing an additional ring E, by Corynebacterium mediolanum strain B-964 was carried out, resulting in the corresponding 4-3-ketones. It was shown that the type of transformation and the yield of the reaction depend on the degree of saturation of the ring E and on the position of the oxygen-containing substituents in it.  相似文献   
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