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91.
Ia I Serkiz A I Lipskaia L B Pinchuk V V Trishin Iu F Kataevski? G N Koval' 《Radiobiologiia》1991,31(5):629-634
Irradiation conditions in which laboratory animals were kept in experimental laboratories of Chernobyl and Kiev after the accident at the Chernobyl A.P.S. are described. The data are presented on the spectral structural and activity of radionuclides in the diet as well as in the organs and tissues of the animals. The radiation loads have been estimated with regard to an external gamma component and the internal one contributed by the incorporated radionuclides. It has been shown that radiation doses received by the animals during their lifetime due to these contributions do not exceed units of cGy. 相似文献
92.
V Ia Gotlib I I Pelevina E F Konoplia A A Al'ferovich A A Konradov 《Radiobiologiia》1991,31(3):318-325
On the basis of their own data and the literature the authors have analyzed the mechanism of biological action of low-level radiation on cells. In studying the harmful effect of gamma-radiation (10-40 cGy) on HeLa cells it was shown that damages occurred in 12 postirradiation generations. Analysis of cell distribution within the colonies has demonstrated that the share of colonies with low cell content and the number of giant cell increase. These data indicate that low-level radiation causes reproductive cell death that can occur not immediately but in later generations. 相似文献
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Blood smears of both male and female chicken Gallus domesticus were analysed by using the following topochemical methods: a) Periodic acid-Schiff (PAS) for glycogen. b) Mercury-bromophenol blue for protein. c) O-Toluidine for myeloperoxidase. d) Sudan black B for lipid. The PAS reaction revealed glycogen in the cytoplasm of all thrombocytes and in a few heterophils. The presence of proteins was evidenced in all types of cells. However variation in the intensity of staining of protein granules was observed in the fusiform structures of the heterophils. A negative reaction for myeloperoxidase was found in all cells. Although some evidence of myeloperoxidase activity was show in the polymorphonuclears it was not enough to ascertain a positive reaction. Lipids were detected in the cytoplasm of few heterophils, eosinophils and monocytes. 相似文献
95.
The potent rat-liver mitogen 4-acetylaminofluorene (4AAF) is shown here to provide an effective replacement for the surgical procedure of 2/3 partial hepatectomy (2/3PH) in the in vivo rat-liver micronucleus assay described by Tates and his colleagues. This protocol modification enables the assay to be conducted on a routine basis. Control observations for both 2/3PH and 4AAF-treated rats are presented, together with evidence indicating 4AAF itself to be without activity in the assay, irrespective of the mitogenic stimulus. The activities of the rat carcinogens DMN, 2AAF, DMH and 6BT, and of the non-carcinogens 4AAF and 4N are demonstrated. Recommendations for the conduct of the modified assay are made. 相似文献
96.
X-IRRADIATION of mammalian cells in culture yields a survival curve of the threshold type (for review see ref. 1). It isjnter-esting to ask how one can enhance the radiation response by small changes of the physical environment of the cells, as can be done chemically, for example, by incorporation of 5-bromo-deoxyuridine into DNA1,2. Elevation of the temperature is a likely prospect for enhancement of radiosensitivity for the following reasons. It is known that proteins are heat labile and that temperature sensitive mutants of bacteria and phage can be obtained for many different enzymes3 which are operative at 37° C but not at 42° or 43°C. For example4, DNA polymerase is reversibly temperature sensitive; it is rendered inoperative above 42°C, but will be functional again when the temperature is lowered. It is not unreasonable to expect that temperature sensitive mutations for many enzymes occur frequently and that the use of temperatures somewhat higher than the normal range at which the cells grow might disclose sensitivities for specific enzymes in normal cells of higher organisms. 相似文献
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