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During the recent 10 years, 1987-1997, syphilis morbidity was found to increase 60-fold in Omsk Province. In 1997 adolescents constituted 6.0% in the structure of persons who contacted the disease. In this year more than 500 adolescent using drugs were registered in the region. The introduction of drugs by injection was practiced by 9.6% of the adolescents. The program aimed mainly at changing the behavior of young people with orientation on the choice of a healthy mode of life and theirs information about risk factors associated with sex transmitted diseases particularly HIV infection is discussed.  相似文献   
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CBA and C57BL mice were immunized intraperitoneally with the conjugates 2,4-dinitrophenyl-bovine gamma-globulin, 2,4,6-trinitrophenyl-bovine serum albumin, diasotated p-aminobenzoic acid-bovine serum albumin, and sulfanylic acid-bovine serum albumin, whereupon migration of hemopoietic stem cells to the spleen was investigated. Immunization with the conjugates haptene--protein was shown in most cases to provoke an intensified migration of hemopoietic stem cells in mice highly responsive to the specific haptene, and at the same time to reduce, as a rule, the intensity of migration in mice of the poorly responsive genotype. It is concluded that the migration ability of stem cells seems likely to be connected with genetic determination of the immune response in mice of different genotypes.  相似文献   
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The cation dye acridine orange (AO) was shown to inhibit ATPase activity of myosin, DTNB-myosin and heavy meromyosin and not to influence that of EDTA-S-1 at low ionic force. The inhibiting effect is concerned with the presence of KCl in solution. The allosteric influence of AO on myosin ATPase activity is discussed and dependence of this effect on charge distribution on the surface of the protein molecule is considered.  相似文献   
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In experiments in vitro, the effects of polychromatic visible (VIS) light combined with polychromatic infrared light (VIS-IR, 480–3400 nm) and the effects of the entire spectrum of VIS radiation (385–750 nm) on viability and proliferative activity of the murine hepatoma cells MH22a were studied. In experiments in vivo, changes in the tumorigenic properties of cells MH22a were studied after the same kinds of light exposure. It was shown that irradiation of hepatoma cells with two kinds of polychromatic light at a wide range of doses (4.8–38.4 J/cm2) did not lead to an increase in the number of dead cells for 24–72 h of cultivation and did not cause deceleration of the hepatoma cell proliferation; moreover, the VIS-IR light at a dose of 4.8 J/cm2 and the VIS light at a dose 38.4 J/cm2 even promoted more intense cell proliferation after 24 h. In cells irradiated with VIS-IR and VIS light, the proliferation index rose by 1.6 and 1.4 times, respectively, and the time of the cells’ number doubling decreased as compared with control. Studying the tumorigenic properties of irradiated tumor cells has shown that, for 30 days after transplantation to syngenic mice C3HA of hepatoma cells 24 h after their irradiation with VIS-IR light at a dose of 4.8 J/cm2, the tumor volume decreased significantly (2.6–4.1 times) at all periods of observation, while the incidence of tumor formation decreased, whereas the survival of the tumor-bearing mice did not change. Transplantation of cells irradiated with the same light at a dose of 9.6 J/cm2 did not lead to significant changes in the tumor volume, the tumor formation incidence, and animal survival. The main contribution to the antitumor effect of VIS-IR light seems to be made by the VIS component, as transplantation into mice of cells irradiated with VIS light alone at a dose of 38.4 J/cm2 also stimulating proliferation of hepatoma cells in vitro resulted in a decrease of their tumorigenic properties. However, the IR component in the combined VIS-IR radiation enhanced the antitumor effect of the VIS light; as a result, it was manifested after use of doses eight times lower (4.8 J/cm2) than in the case of VIS light alone (38.4 J/cm2). Mechanisms of the decrease of tumorigenic properties of hepatoma cells after irradiation with polychromatic light at doses stimulating their proliferation in vitro are studied.  相似文献   
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Dependence of the rate of ATP hydrolysis with subfragment-I and temperature of SF-I, denaturation on the concentration of heavy water in solution was studied. The value of kinetic isotope effect V/Vx linearly increases with the rise of the volume portion of heavy water in solution and at X-1 it equals 1.9. The temperature of protein denaturacticn increases with X rise, the pattern of this relationship looking as an arched curve. The results differ from those earlier obtained on myosin which points to the absence of essential contribution of structural dynamic changes to enzymic hydrolysis of ATP by subfragment-I.  相似文献   
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