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571.
572.
Based on the analysis of the dielectric Maxwell's relaxation in a double-layer construction of protein and lavsan films an electrodeless method for measuring a. c. conductivity of protein films was developed. The conductivity of BSA films soaked in electrolyte solution was shown to retain its ionic character at subzero temperatures up to -50 degrees C in spite of an about 3-orders drop in the conductivity at 0 degrees C.  相似文献   
573.
Combined use of vaccine and immunomodulators such as ridostin, inosiplex and polyribonate against acute encephalomyelitis of humans (AEMHs) was studied. It was shown that low immunogenic doses of the vaccine did not provide a protective action against the virus of AEMHs while after administration of the vaccine in combination with the immunomodulators there was protection in all the groups of the animals exposed to the low immunogenic doses of the vaccine during the first immunization. It was noted in regard to all the combinations of the immunomodulators and vaccine used in the low immunogenic doses that the level of the increase in the titer of the virus-specific antibodies, the proliferative activity to the specific antigen and mitogens and of interferon induction depended on the immunomodulator type. At the same time, it was found that the marked production of interferon within the first 24 hours observed after the use of the combination of inosiplex, ridostin and the vaccine resulted in increased activity of natural killer cells and lower proliferative activity of cells and production of virus-specific antibodies. This was indicative of the necessity of choosing the immunomodulators, their doses and time of the administration in relation to the immunization.  相似文献   
574.
575.
It is shown that the average number of sister chromatid exchanges (SCE) per one cell in patients with tuberous sclerosis as well as in those with Recklinghausen's neurofibromatosis do not differ from the control. But the non-parametric methods of analysis have revealed differences in the spontaneous level of SCE is patients with tuberous sclerosis, while no such differences were revealed in patients with Recklinghausen's neurofibromatosis.  相似文献   
576.
577.
An expression for the partition function of the model including only two parameters-U (energy of hydrogen bond) and Q (the number of conformations of the repeating unit) with Hamiltonian is obtained. This expression has the form of algebraic series with the number of members approximately N3, N being the length of the chain. The results of calculations of the temperature relationship of helicity degree are presented for different values of N. The transition width and the parameter of cooperativity are calculated.  相似文献   
578.
mutation Y168H of the human phenylalanine hydroxylase (PAH) gene determining phenylketonuria was described only twice: in a patient from Catalonia (Spain) and by us in a patient from Western Siberia (Russia). The association of Y168H in these families with allelic variants of STR and VNTR repeats and a number of neutral point polymorphisms of the PHA gene (IVS3nt-22C > T, Q232Q, V245V, L385L) was studied in this work. The Y186H mutation in these families was found to be associated with different haplotypes. Strong linkage of the selected markers and the mutation region excludes recombination as a possible cause of association of Y168H with different haplotypes. It was concluded that Y168H occurred independently in different populations.  相似文献   
579.
580.
Proteoglycans were isolated from the extracellular matrix (ECM) of L6J1 rat myoblasts; their influence on myoblast adhesion has been studied. Proteoglycan digestion with chondroitinase AC and heparinase III, which degrade polysaccharide moieties, has revealed that chondroitin sulfate proteoglycans are a major class of myoblast extracellular matrix proteoglycans. Electrophoresis of enzymatically processed proteoglycans was used to examine their core proteins. Myoblast adhesion was suppressed by proteoglycans or a mixture of proteoglycans and a fibronectin-extracellular matrix. Myoblast adhesion to a substrate composed of fibronectin and proteoglycans is restored after the substrate was treated with chondroitinase AC. In conclusion, proteoglycans of L6J1 rat myoblast ECMs were isolated and purified. Chondroitin sulfate proteoglycans are a major class of proteoglycans. Isolated proteoglycans suppressed myoblast adhesion; the effect was mediated by polysaccharide moieties of proteoglycans.  相似文献   
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