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61.
Stability characteristics of the laccases of the basidiomycetes Coriolus hirsutus and Coriolus zonatus were measured comparatively at temperatures of 25 and 40°C in the presence of various effectors (proteins, salts, polyalcohols, polyacids, and polyelectrolytes). Stabilization effects of cations on the laccases from C. hirsutus and C. zonatus decreased in the descending series Cu2+ > Mg2+ > Ca2+ and Ca2+ > Mg2+ > Mn2+, respectively. Tween 20 caused insignificant stabilization of the two enzymes. The C. zonatus laccase was also insignificantly stabilized as a result of treatment with bovine serum albumin. The enzymatic activity of the laccase preparations from C. hirsutus and C. zonatus was conserved virtually completely after vacuum drying (84 and 93%, respectively). The most effective stabilizer of the C. hirsutus laccase was found to be dextran (17 kDa). Dry preparations treated with this agent conserved up to 95% of the enzymatic activity. The most effective stabilizer of the C. zonatus laccase was polyacrylic acid (102% of the initial activity).  相似文献   
62.
Allelic polymorphism of five microsatellite loci of the human Y chromosome (DYS19, DYS390, DYS391, DYS392, and DYS393) was analyzed in samples of male populations from Ukraine, Russia, and Belarus (152 subjects in total). The allelic diversity indices (D g) were determined for all loci; they varied from 0.23 to 0.72. The mean values of this parameter in the Ukrainian, Russian, and Belarussian populations were 0.45, 0.47, and 0.52, respectively. A total of 53 different haplotypes were found in 152 subjects from three populations. The most frequent haplotype was found in 14.5% of the subjects, whereas 35 haplotypes (23%) were each found in only one person. The haplotypic diversity index (D hp) was 0.94. The genetic distances between the populations studied and some populations of Western and Central Europe were estimated. These data were used to construct a phylogram (tree) of genetic similarity between the populations, which demonstrated that the three Eastern Slavic populations are genetically close to one another and remote from Western European populations.  相似文献   
63.
Functional organization of lymphatic microvessels of the rat mesentery]   总被引:1,自引:0,他引:1  
Lymph flow as measured with biomicroscopic and speckle-interferometrical techniques was very unstable and its rate did not depend on lymphangion diameter in the rat mesentery. A correlation was found between amount of cells in the lymph flow and other indices of lymphangion functions. All microvessels with phasic contractions and/or working valve were revealed as having a lymph flow. The phasic activity and the valve work correlated with each other. The higher the amplitude and frequency of the phasic activity and the longer the contraction cycle, the higher was the rate of the valve work.  相似文献   
64.
The results of prolonged dynamic observations on the state of herd immunity against poliomyelitis virus in an industrial city are given. The survey covered 1304 children. The data thus obtained, when synchronized according to years, seasons, the age of the surveyed children and the methods used in the survey, indicated that in every age group 20-30% of children had no antibodies to group I poliomyelitis virus and 30% of children had no antibodies to group III poliomyelitis virus. The geometrical mean of antibody titers to different types of the virus fluctuated from 1.8 to 4.6 log2, the lowest value being obtained for the titer of antibodies to type III poliomyelitis virus. During the whole period of immunological control (1974-1978) no mass circulation of poliomyelitis virus and no outbreaks of poliomyelitis were registered despite the fact that a considerable proportion of children having no antibodies to one or several types of the virus was constantly present among the most susceptible part of children.  相似文献   
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Reactogenic property and immunological efficacy of the paratyphoid preparation containing a complex of O-, K- and H-antigens obtained by single-stage antigens extraction were studied in a limited group of volunteers (22 persons). The antigen gave no untoward reactions and proved to be safe when given orally in doses of 25 to 150 mg. Paratyphoid B antigen was characterized by a marked immunization activity and stimulated formation of specific paratyphoid O-, K- and H-agglutinins and antibodies of the IgA,- IgG,- and IgM-classes.  相似文献   
67.
Cationic proteins of brain lysosomes (LCP), myelin (MCP) and nuclear histone fractions from calf thymus (T) and rat brain (B) are shown to increase at different degree the permeability of brain lysosomes and neutrophiles for acid RNAase, acid phosphatase, catepsin D and beta-galactosidase. According to the effectivity, basic proteins can be listed in the following order: for lysosomes-f2aT, F3B, f3T greater than total histones B, f2bT greater than f2B greater than LCP, MCP greater than flT, flB; for neutriphiles-f3T larger than or equal to total histones B larger than or equal to f3b MCP larger than or equal to f2aT, f2bT greater than f2B greater than LCP greater than flB greater than flT. Fractions f2a and f3 considerably increased the release of acid RNAase from lysosomes in very low concentrations beginning from 0,2 mug/ml, while the release of catepsine and acid phosphatase took place beginning from 5-10 mug/ml. The effect of lysosome and myelin cationic proteins on the release of hydrolases occurred at concentrations ten to hundred times higher.  相似文献   
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Actinomycin D specifically quenches the fluorescence of acridine orange and quinacrine bound to deoxyribonucleic acid in cytologic preparations, but does not change the fluorescence of these fluorochromes bound to RNA. The following fluorescence-cytochemical applications of techniques based on these findings can be suggested: (a) distinction between deoxyribonucleic acid and ribonucleic acid; (b) detection of double-stranded virus ribonucleic acid; (c) approximate estimation of the lengths of A-T sequences in deoxyribonucleic acid molecules.  相似文献   
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