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991.
The authors carried out a comparative analysis of the changes in the antibody synthesis and their immunological maturation in the immunization with various doses of the Vi-antigen of linear rats differing by the capacity to deposit this antigen. August rats with a high capacity to deposit the Vi-antigen (in comparison with Wistar rats in which this capacity was less) were characterized by an increased level of highly avid antibodies. The interlinear differences were found in the character of the changes in the antibody synthesis depending on the immunizing dose of the antigen. Genotypical peculiarities of the immunological maturation of the antibodies were demonstrated. The authors suppose that the described phenomenon was genetically determined and referred to the factors determining the individual immunological reactivity. In the choice of the optimal immunizing doses of the antigens the authors recommend complex determination of the antibody level and the degree of their avidity.  相似文献   
992.
A quantitative electron microscopical investigation of the sinus node of the atrioventricular His' bundle and of the perinodal working myocardium in intact rats and 7, 15 and 30 days after right-sided vagotomy has revealed variable character of changes in the neural elements of the zones mentioned. Certain ultrastructural rearrangements in the neural apparatus are described; they reflect a combination of destructive and regenerative processes in the heart under vagotomy. Thirty days after the operation, regeneration of the neural elements in the sinoauricular area is of restorative and in the atrioventricular area--of excess character. The data are presented on dynamics of changes in the diameter of the amyelinated neural fibers in the cardiac areas investigated. Participation of both nervi vagi in innervation of the main and additional pacemakers of the organ is discussed.  相似文献   
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996.
The alkaloid composition of mycelium and culture liquid filtrate of the fungus Penicillium roqueforti IBPM-F-141 was studied. The new metabolite--3,12-dihydroroquefortine, a derivative of roquefortine, the main component of the alkaloid fraction of this culture, has been isolated for the first time. The structure of 3,12-dihydroroquefortine was determined by chemical and physico-chemical methods. In addition to roquefortine and 3,12-dihydroroquefortine, representatives of a new alkaloid group, the clavine alkaloids, e. g. isofumigaclavine A, isofumigaclavine B and festuclavine, were also isolated and identified. The data on the content of these compounds in mycelium and culture medium are presented.  相似文献   
997.
Supplementary effect of high temperature (37 degrees C) an hour after the treatment of mature sperms of Drosophila with ethylene imine resulted in an increased level of the inactivation (the frequency of dominant lethal mutation). The frequency of complete mutations (recessive sex-linked lethal mutations) increased by the supplementary effect of high temperature at low doses of E1, and it did not change under a comparatively high dose of the mutagen. The frequency of mosaic mutations decreased under the effect of high temperature at both doses of E1. No effect of high temperature was observed in 4 and 24 h after the E1 treatment. The results obtained are discussed in connection with the proportion of inactivation and mutagenesis under the effect of chemical mutagens on Drosophila germ cells.  相似文献   
998.
A selective uptake of ethanol by presenting its 5% solution as the only source of fluid was elaborated in rats for 2 months. It was found that lithium chloride injected intravenously in a dose of 35 mg/kg twice per 24 hours for 14 days depressed the ethanol preference causing a motivation inversion whose mechanism was associated with the changes in the activity of the hypothalamic centres of the neuroendocrine regulation. A possibility of lithium salts in the therapy of chronic alcoholism is discussed.  相似文献   
999.
A parallel histological and electron microscopic study of the capillary network of interalveolar septa has shown that in this microstructure there is only one two-dimensional capillary network, common for adjacent alveoles. In septal spaces of interalveolar septa the collagenic fibrils form an even thin network and additional collagenic bundles. The latter are mainly found in intercapillary septal spaces. The elastic fibres in interalveolar septa are found rarely, no interstitial cells being found at all.  相似文献   
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