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51.
The antioxidant and peroxidase activities of mixed saliva have been investigated during test loads in control group and patients with caries and combination of caries with inflammatory periodontal diseases. Antioxidant activity of saliva was significantly decreased in the last two groups and so its was corrected by means of xidiphone.  相似文献   
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53.
Using the immunofluorescence approach, we have determined that the recently detected protein kinases, among which are RhoA-activated kinase, integrin-linked kinase, zipper interacting protein kinase, and death-associated protein kinase, which are capable of phosphorylating myosin, are localized in the Z-lines sarcomeres of human myocardium. Additionally, we studied the content of integrin-linked and zipper interacting protein kinases in human embryonic myocardium, as well as in normal and hypertrophic adult human heart. The content of these protein kinases in adult normal myocardium increases in comparison with the embryonic heart. The content of integrin-linked and zipper interacting protein kinases in hypertrophic myocardium is higher compared with the normal adult heart. The data obtained suggest the involvement of these protein kinases in the development and hypertrophy of human heart.  相似文献   
54.
A new strain producing extracellular laccase (Cerrena maxima 0275) was found by screening of isolates of Basidiomycetes, and the dynamics of laccase biosynthesis by this strain was studied. The enzyme was purified to homogeneity. The molecular weight of the enzyme is 57 kD, and its pI is 3.5. The activity is constant at pH values in the range 3.0-5.0. The temperature optimum for activity is 50°C. The thermal stability of the laccase was studied. The catalytic and Michaelis constants for catechol, hydroquinone, sinapinic acid, and K4 Fe(CN)6 were determined. The standard redox potential of type 1 copper in the enzyme is 750 ± 5 mV. Thus, the investigated laccase is a high redox potential laccase.  相似文献   
55.
Copper-containing sites of laccases isolated from the Basidiomycetes Coriolus hirsutus and Coriolus zonatus were characterized by optical methods and EPR spectroscopy. Methods for preparation of fungal laccase derivatives free from type 2 copper ions were compared. The data of EPR spectroscopy and spectrophotometric titration of copper sites showed that only a modified method based on the use of bathocuproine as a chelator for type 2 copper yielded laccase derivatives completely free from type 2 copper. The original enzymes can be reconstituted from the derivatives by dialysis under anaerobic conditions, resulting in complete recovery of native conformation of the protein molecule and the structure of the copper-containing site.  相似文献   
56.
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   
57.
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   
58.
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   
59.
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   
60.
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