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991.
The study of the effect of gamma globulin introduced in different doses (0.5 and 0.25 ml/mg) in combination with Fermi rabies vaccine (observations on humans were made) and with cerebral rabies vaccine inactivated by UV irradiation (in animal experiments) demonstrated that the injection of the higher doses of gamma globulin resulted in lower geometrical mean of antibody titers. Therefore, in combined administration of rabies vaccine and gamma globulin for postexposure rabies prevention it is advisable to reduce the dose of gamma globulin by one-half.  相似文献   
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A method is proposed for assessing the biocidal efficacy of water-dispersed nanoparticles of silver. It is based on negative chemotaxis of the plasmodia of the slime mold Physarum polycephalum. Biocidal and repellent effects were compared for silver nanoparticles, Ag+ ions, and AOT in solution and in the agar gel. In such characteristics as increasing the period of auto-oscillations of contractile activity, decreasing the area of spreading on substrate, and substrate preference in spatial tests, silver nanoparticles proved to be substantially more effective than Ag+ and AOT. The lethal concentrations of the nanoparticles were close to those found earlier for bacteria and viruses. The chemotactic tests allow quantitative assessment of the biological reaction and monitoring its dynamics; in resolution, they are superior to the tests based on the lethal action of biocidal agents.  相似文献   
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Abstract— The Nucleic acids were measured in developing retinae of normal (DBA) mice and those afflicted with an inherited degenerative disease (C3H). The content of RNA in normal and C3H retinae increased to a maximum at 5 days of postnatal age. Thereafter, that of C3H retinae declined to a value lower than the normal. The content of DNA in normal and C3H retinae was maximal at 10 and 5 days of postnatal age, respectively. By 20 days, it declined in both retinae to nearly adult values. The DNA/RNA ratio of normal adult retinae was about 3, while that of C3H adult retinae was nearly 1–5. It is proposed that the photoreceptor cells possess a smaller cytoplasmic volume and a larger DNA/RNA ratio than the cells of the inner retina. The loss of DNA in developing normal and C3H retinae appears to result from cellular death. It was calculated that approximately 1 million cells in normal and 6 million cells in C3H retinae disappear during development. Cellular death in C3H retinae may not be restricted to the photoreceptor population.  相似文献   
998.
During an ultrastructural study of small-intestinal mucosa from a patient suffering from alpha-chain disease organisms were identified within the epithelial cytoplasm which showed the fine structural features of the coccidian group. Though coccidiosis is well recognized as causing a diarrhoeal and often lethal illness in animals it has been neglected as a cause of disease in man. Thus this finding may be significant and warrants further investigation into its possible role in the pathogenesis of alpha-chain disease.  相似文献   
999.
Toluidine blue, applied to frog sperm under appropriate conditions, inactivates specifically the sperm nucleus, leaving the extranuclear parts of the cell undamaged. Thus, the dye-treated spermatozoa stimulate eggs to cleave normally, but contribute no chromosomes to the resulting embryos, which develop as typical gynogenetic haploids. The concentration of dye required to produce this inactivation varies with pH. Measurements made over the entire pH range which can be tolerated by sperm cells showed that in the lower part of the range (5 to 7) the effective dye concentration was about 5 x 10(-6)M; in the intermediate range (7 to 8.5) it was 1 x (-6) to 1 x (-7)M; and for the higher pH values (8.5 to 10.0) it was about 5 x (-8)M. Using sperm suspensions containing 1500 cells per c. mm. these concentrations of dye produced specific inactivation of the sperm nuclei within 7 to 60 minutes at 18 degrees C. Tests of the reversibility of the inactivation were made by transferring the sperm from the dye to a dilute Ringer's solution after a known degree of inactivation had been produced. Following removal of the dye the sperm cells were tested on eggs over a period of 2 hours. During this time there was no indication of a reversal of the inactivation. Microscopic observations of sperm treated with (-5)M or 5 X (-5)M dye show that the dye is taken up by the sperm nucleus, which is faintly but definitely stained. The dye appears to be uniformly distributed in the nucleus, while extranuclear structures remain unstained. Measurements of the amount of dye bound per sperm nucleus indicate that the minimal quantity required for complete inactivation is about 6.7 x (-18) mole, while the maximal amount which can be bound without injury to extranuclear structures is about 1.5 x (-16) mole. The value obtained for the minimal requirement (6.7 X (16) mole = 4 X (6) molecules) suggests that there are roughly 4 million binding sites in the nucleus which, when blocked by dye molecules, somehow prevent the sperm chromosomes from participating in the development of the egg.  相似文献   
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