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951.
The identification of hereditary variants of cutaneous melanoma and analysis of the role of hereditary factors and syndromes predisposing to cutaneous melanoma were carried out. The involvement of individual nevus phenotypes in the development of this disease was determined. Based on a survey of recent molecular biological data and our studies, the etiological and genetic heterogeneity of cutaneous melanoma is reported. In relatives of patients with cutaneous melanoma and persons with multiple pigmented nevi, the malignant tumors proved to be differentiated in the direction of the neural crist tissues and/or derivatives of cutaneous mesenchyma. Based on the evidence obtained, the approaches have been developed to formation of risk groups for the purpose of early diagnostics of cutaneous melanoma.  相似文献   
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Effect of 4,4-dyisotiocyanostilben-2,2-disulfonate (DIDS) and 1-ftor-2,4-dinitrobenzol (NDFB) on the rate of phosphate ion transport in erythrocytes, filtrability and thermal stability of erythrocytes and on the structural state of the erythrocyte membrane estimated by UV-fluorescence, PAAG--electrophoresis and measuring of the activity of membrane-bound acetylcholinesterase (AChE) has been studied. Unpenetrating anion transport inhibitor DIDS is shown to induce structural modifications of bands 3 of protein and AChE, while DNFB penetrating the membrane causes a significant reorganization of many membrane proteins (including spectrin) resulting in changes of transport and mechanical properties of erythrocytes.  相似文献   
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The effect of hexylresorcinol (HR), a chemical analogue of microbial anabiosis autoinducers of the alkylhydroxybenzene (AHB) group, on the stability of biological membranes and monolamellar liposomes formed of egg phosphatidylcholine (ePC) was studied. According to spectrophotometry and electron microscopy studies of HR-loaded liposomes in the presence of a surfactant Tween 20, the critical ratio between HR and ePC for liposome preservation was found to be close to equimolar. The trends in HR influence on membrane structural organization and stability of liposomes were also confirmed in experiments on intact bacterial cells explaining non-species-specific effect of AHBs. The demonstrated high efficiency of AHB biocides may be used in material and equipment protection against biocorrosion.  相似文献   
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The hummock-hollow relief is typical of the Angara region, which determines mottling of the soil cover, its complexity. We examined how microelements (elementary composition), exchangeable Ca and Mg, and biogenic parameters (humus composition, biological activity) behave in soils. The topical problems concerning the studied object are discussed.  相似文献   
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Nisin synthesis by Streptococcus lactis, strain MGU, grown as a combined culture together with Proteus vulgaris and Bacillus mesentericus under stationary conditions or with stirring does not depend on the quantity of inoculated associated cells. Nisin synthesis in the combined culture drops down by 10-20% at the initial pH 7.5 of the growth medium which is unfavourable for S. lactis producing nisin. The level of nisin biosynthesis does not rise when the pH of the medium is adjusted (either naturally or artificially) to 6.6-6.8 in the presence of glucose and yeast autolysate. S. lactis inhibits the growth of B. mesentericus when grown together with it whereas P. vulgaris inhibits the growth of S. lactis in their combined culture.  相似文献   
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