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91.
James F. Richards Kulgite Lit Roland Fuca Catherine Bourgeault 《Biochemical and biophysical research communications》1981,99(4):1461-1467
Several species of ornithine decarboxylase were separated by chromatography of rat thymus and kidney extracts on DEAE-Sepharose CL-6B. One major and one minor species were absent from thymus of rats two hours after hormone treatment but otherwise, the elution profile was identical to thymus from control animals. The elution patterns of ODC activity in kidneys of rats treated 2.5 or 5 hours before sacrifice with dexamethasone differ from that of control kidney and from each other. Enzyme from kidneys early after hormone treatment is eluted earlier than enzyme from control tissue, while at 5 hours, the enzyme is eluted much later than in the control. This suggests that the hormone-induced activity is subsequently modified. 相似文献
92.
A F Wright 《BMJ (Clinical research ed.)》1982,285(6342):609-611
93.
J F Searle 《BMJ (Clinical research ed.)》1984,288(6435):1998-1999
94.
F. CROUTE D. DUPOUY J. P. CHARLEY J. P. SOLEILHAVOUP H. PLANEL 《The Journal of eukaryotic microbiology》1980,27(1):132-135
SYNOPSIS Catalase activity of Paramecium tetraurelia decreased during autogamy and recovered to normal 5 days later. Autogamy also caused changes in the ciliate's sensitivity to natural ionizing radiations—the decrease in cell growth rate previously described in shielded cultures did not occur when autogamous cells were used. Maximum effect of shielding was observed in 11-day-old postautogamous cells. the role of the catalase in the mechanism of natural irradiation effect is discussed. 相似文献
95.
Based on experiments on agarose gels and tissue, a procedure has been developed which greatly improves the sensitivity and the specifity of the Kossa method for demonstrating calcium in tissue. Tissue calcium is immobilized by acetonic oxalic acid, which simultaneously removes the other sorts of anions capable of precipitating silver ions (e.g. phosphate, carbonate). The resulting submicroscopic grains of calcium oxalate are converted first into silver oxalate then into metallic silver by a treatment with silver nitrate followed by an ultra-violet irradiation (Kossa reaction). These submicroscopic metallic silver grains are enlarged up to microscopic visibility by means of physical development, which makes the staining highly sensitive. Co-staining of the argyrophil sites in the tissue is totally suppressed by various tricks, which render the silver staining selective for calcium. 相似文献
96.
E. Molina Grima J. A. Sánchez Pérez F. García Camacho F. G. Acién Fernández J. M. Fernández Sevilla F. Valdés Sanz 《Biotechnology letters》1994,16(10):1035-1040
Summary Eicosapentaenoic acid (EPA) volumetric productivity from an outdoor chemostat culture ofPhaeodactylum tricornutum UTEX 640 in a 50-l tubular photobioreactor varies with dilution rate, reaching a maximum of 47.8 mg l–1 d–1 at D=0.36 d–1. Continuous culture at high dilution rates' is proposed as the most adequate operating mode to maximize polyunsaturated fatty acid production. 相似文献
97.
98.
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
99.
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
100.