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91.
92.
The influence of H2O2 at concentrations of 10(-8)--10(-2) mol/l on neutrophil ability to generate the reactive oxygen and chlorine species (ROCS) and secrete myeloperoxidase (MPO) was studied, and H202 injurious effect on neutrophils was also investigated in this work. It was revealed that H2O2 at concentrations of 2 x 10(-3)--2 x 10(-2) mol/l induced disturbance of the neutrophil membrane barrier properties and lactate dehydrogenase release. The incubation of the neutrophils with the addition of 10(-4)--10(-7) mol/l H2O2 led to an increase in the cell ability to generate ROCS during phagocytosis and decreased neutrophil ability to secrete MPO and ROCS in extracellular medium during adhesion. The mechanisms of H2O2 effect are coupled with arachidonic acid metabolism. Inhibition of metabolic pathways of 5-lipoxygenase or cyclooxygenase increased the destructive effect of H2O2 on the cells. Five-lipoxygenase way prohibition led to cancellation of H2O2 influence on MPO and ROCS secretion and to enhancement of H2O2 effect on neutrophil ability to generate ROCS during phagocytosis. The data obtained testify to the high neutrophil resistance to destructive effect of H2O2 and confirm the regulatory role of H2O2 with respect to the neutrophil functions. 相似文献
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94.
The regularities in the formation of different types of Anura coccygeosacral articulations have been determined. A review of factors that affect the form of this articulation is presented. It has been established that the determinant role in the formation of a moveable or immoveable articulation is played by the topography and time of the appearance of muscles in the coccygeosacral area. The proposed mechanisms explain not only the diversity of structural norms depending on this feature, but also options of individual variability. 相似文献
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96.
Materials are presented concerning the analysis of blood groups in the Yakutsk aboriginal cattle (n = 960) and its hybrids (n = 145) bred in Verkhoyansk and Yakutsk regions of Yakutskaya ASSR with respect to the problems of its origin. The genetic similarity of the Yakutsk cattle and its hybrids was evaluated; the cattle populations were studied in various years. The experiment also involved some hybrids bred in the northern part of the Soviet Union. The strongest similarity was found for the Yakutsk aboriginal breed and the cattle bred in Kalmytskaya and Buryatskaya Regions (0.841-0.839), i.e. those which are ascribed to the same group, according to their origin. Similarity with the Ashire and hybrids of Zebu and Black and White cattle was found to be less pronounced. The frequencies of antigens ranged from 0.2 (the antigen H") to 100% (the antigen F). The antigen frequencies were found to be higher in purebred animals, as compared to the hybrids almost within the whole antigen spectrum. 相似文献
97.
E. V. Popova N. S. Domnina N. M. Kovalenko S. V. Sokornova S. L. Tyuterev 《Applied Biochemistry and Microbiology》2018,54(5):535-539
The effect of immune modulators based on chitosan, vanillin, and salicylic acid on wheat resistance to brown rust (Puccinia recondita) and dark brown spot (Cochliobolus sativus) was studied. It has been established that chitosan and modified salicylic acid increases the resistance of wheat to both pathogens, whereas chitosan containing vanillin effectively induces resistance only to the hemibiotroph of C. sativus. The molar ratio of vanillin and salicylic acid (1: 1–1: 2) in hybrid immune modulators was determined to obtain high inducing activity with respect to the biotroph of P. recondita and the hemibiotroph of C. sativus. When a relationship between wheat and hemibiotroph C. sativus forms, a direct relationship is observed between the activity of antioxidant enzymes and the intensification of disease development. 相似文献
98.
E. V. Mashkina K. A. Kovalenko T. A. Marakhovskaya K. N. Saraev A. A. Belanova T. P. Shkurat 《Russian Journal of Genetics》2016,52(8):853-859
In the present study, the frequencies of genotypes and alleles of candidate genes with respect to polymorphisms associated with increased pregnancy loss in the first trimester of pregnancy, including MMP1–1607insG, MMP9 A–8202G, and TIMP1 С536T, were reported. The frequency of homozygotes for allele MMP9 A–8202 was increased by a factor of two among women with miscarriage in the first trimester compared to the control. Significant models of interaction of genes MMPs and TIMP1 were revealed. The genotypes of genes MMP1 (rs1799750), MMP9 (rs11697325), and TIMP1 (rs11551797) increasing the risk of pregnancy loss in the first trimester were determined. 相似文献
99.
Natural killer cells (NK cells) are traditionally attributed to the innate immune system. It is considered that previously received stimuli have little effect on the functioning of these immune cells. Indeed, NK cells even without prior sensitization provide a rapid effector response against tumor, virus-infected, or otherwise damaged cells. They have a limited repertoire of receptors, the expression of which does not require somatic recombination. However, recent data indicate that NK cells may acquire the properties specific to adaptive immune cells. In particular, NK cells have been shown to possess the features of immunological memory, namely, the ability to more quickly and effectively respond to a repeated stimulus. The mechanisms of memory acquisition in NK cells differ from those implemented in T and B lymphocytes and are still rather vague. Presumably, some of these mechanisms underlie the significant phenotypic and functional NK cell diversity emerging during their differentiation. The recent data accumulated in this area considerably change the existing immunology paradigm, which postulates a clear delineation of the adaptive and innate immune cells. The published data on phenotypic and functional characteristics of NK cells and particular changes in these characteristics during NK cell differentiation and generation of memory-like NK cells are reviewed. 相似文献
100.
The component composition and antiviral properties of the mannan-containing preparations were studied. These preparations were extracted from some laboratory and commercial specimens of the fodder yeast cultivated on different substrates. It was shown, that the main component of pure preparation was the mannan which had molecular mass near 13 kDa. The monosaccaride composition of mannan component was varied depending on the source, degree of purification, methods of purification of the preparations. However, the crude and pure mannan preparations activity relatively to VTV was approximately equal. 相似文献