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991.
The effect of inert helium and argon gases on the tissue respiration has been studied on lymphocyte suspensions of white rats. It is shown that normoxic helium-oxygen mixture induces almost a two-fold increase of the O2 uptake by lymphocytes as compared with the control (air). No deviations in the value of the studied parameter are revealed in case of replacement of nitrogen from air by argon. Significance of the membrane structure in realization of effects of inert gases is under discussion. 相似文献
992.
A total of 626 patients undergoing a prostaglandin-induced abortion, the majority in the second trimester, have been analysed for complications occurring during inpatient treatment. Of the last 155 consecutive patients 143 were critically assessed six to eight weeks after abortion for morbidity occurring during their early recovery period.Blood loss of 250 ml or more occurred in 68 patients, pyrexia in 34, pelvic infection in three, and readmission in 14 of the 626 patients studied, and a transfusion was required in eight.Bleeding after abortion stopped within six weeks in all 143 of the 155 consecutive patients assessed but three required readmission for uterine curettage. Menstruation was re-established within six weeks of abortion in 106 patients.The incidence of operative morbidity was similar to that reported for first trimester abortion and better than that in most reported series of second trimester abortions. 相似文献
993.
Mild micrococcal nuclease treatment of rat and mouse nuclei and fractionation were based on the method of Tata and Baker. Three chromatin fractions, S, P1, P2, were separated, and for each of these fractions the sensitivity to the DNase 1 action was determined. The relative content in these fractions of non-transcribed DNA sequences was established by hydridization with a mouse satellite DNA, and the relative content of transcribed DNA sequences--by hydridization with DNA synthesised on the total poly (A) mRNA. None of the fractions displayed the properties characteristic of active chromatin. 相似文献
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996.
I H?nes 《Zeitschrift für allgemeine Mikrobiologie》1983,23(3):163-171
Comparative studies on the activities of isocitrate lyase (ICL) and malate synthase (MS) were carried out with Saccharomycopsis lipolytica incubating the yeast on media with different carbon sources. When cells were incubated in minimal medium with glucose, the activities of both enzymes were very low. In contrast, in minimal medium with acetate enhanced enzyme activities could be demonstrated. It is probably that the synthesis of ICL is repressed in presence of glucose. Furthermore the activity of ICL was inhibited by tricarboxylic acid cycle intermediates like succinic acid and oxalacetic acid. It was concluded that the syntheses of enzymes are derepressed. When cells of Sm. lipolytica were incubated in minimal medium with acetate, a high enzyme activity is evident. Synthesis of ICL on acetate was inhibited by cycloheximide and actinomycin D. The results were discussed comparing them with data obtained from other organisms. 相似文献
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Earlier we have revealed in Djungarian hamster DM-15 cells three chromosomal segments (2p22, 5p1, 7q23-25) that are specific for transposition of amplified mdr1 genes from the site of location of resident gene copy (it was mapped to 4q21-23). In situ hybridization revealed in wild type cells no mdr1 homologous sequences in all these three segments. In this work we studied distribution of chromosomal breakages induced in DM-15 cells by aphidicolin, 5-fluorodeoxyuridine or N-phosphonacetyl-L-aspartate. The data obtained indicate that two of above mentioned segments. 2p22 and 7q23-25, contain no fragile sites. So, specificity of these segments for the transposition of amplified mdr1 genes is not due to their particular instability or to the presence in them of sequences homologous to amplifiable selectable gene. 相似文献