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Summary Sera from 21 cases of prolonged apnoea which showed normal phenotype (UU) on the basis of dibucaine and fluoride inhibition were re-examined by replacing the substrate benzoylcholine with succinylcholine (suxamethonium). 9 samples had normal enzyme activity but low dibucaine number (DN=<20) indicating the atypical variant; 6 sera showed no detectable enzyme activity. The remaining 6 samples had enzyme activity and DN comparable with healthy controls. The occurence of new variants of serum cholinesterase sensitive only to succinylcholine is suggested.Dedicated to Prof. Dr. med. J. Kühnau on his 75th birthday. 相似文献
43.
Cycling populations of Aedes aegypti were set up in cages and managed in such a way that the populations had a maximum of threefold recovery potential in response to control measures. Into three such populations daily releases were made of males which had been chemosterilised, or were double translocation heterozygotes (T1T3) or T1T3 with sex ration distortion (DT1T3). Eradication of the populations was achieved with all cases, but the rate of suppression was markedly slower with T1T3 than the other two systems, with which the rates were similar. T1T3 and DT1T3 releases introduced considerable inherited genetic loads into the target populations. The results were in general agreement with computer predictions. 相似文献
44.
Identification and properties of renal mineralocorticoid receptors in relation to glucocorticoid binders in rat liver and kidney. 下载免费PDF全文
M K Agarwal 《The Biochemical journal》1976,154(3):567-575
The binding of the natural mineralocorticoid aldosterone and the glucocorticoid corticosterone to macromolecules in rat liver and kidney cytoplasmic fractions was compared by various chromatographic procedures. Equilibration of kidney cytosol with 10nM-aldosterone, either alone or in the presence of a competing steroid, was ideal for ionexchange chromatography of DEAE-cellulose DE-52, and revealed the presence of four sorts of binding components. One of these, eluted in the 0.001M-phosphate pre-wash, and another, less abundant, forming a peak at 0.006M-phosphate, did not bind corticosterone at equimolar concentrations, and appear to constitute the mineralocorticoid-specific 'MR' receptor in rat kidney. They could not be detected in the liver. Radioactivity eluted in the 0.02 and 0.06M-phosphate regions on DEAE-cellulose DE-52 appears to be due to [3H]aldosterone binding to glucocorticoid-specific 'GR' receptors and to transcortin respectively, since labelling was greater with corticosterone even at 10 nM than with the mineralocorticoid at 100nM and since [14C]corticosterone bound to blood serum transcortin was always co-chromatographed in the 0.06M-phosphate region. These two components appear to be identical with those in the liver and could be labelled maximally only by 100nM-corticosterone. The separation between specific mineralo- and glucocorticoid-binding species was less clear when chromatography was attempted on DEAE-Sephadex A-50 columns, possibly because of disaggregation into subunits in the presence of the high KC1 concentrations required for elution. Competitive binding followed by filtration through Sephadex G-200 gel indicated that cellular MR binders, unlike GR receptors, exist mostly as high-molecular-weight aggregates, although both appear to exhibit a comparable monomeric molecular weight of approx. 67000. 相似文献
45.
Summary A micromodification of the method of HGPRT and APRT assay is described, which measures the incorporation of 14C hypoxanthine and 14C adenine into cultured skin fibroblasts and amniotic cells grown on microtiter plates. Only about 10 000 cells are needed per assay. By this method HGPRT deficient cells can be easily distinguished from normal cells. Investigations with respect to the effect of substrate concentrations and time of incubation have been carried out on some normal fibroblast cell lines, amniotic cell lines and 3 Lesch-Nyhan cell lines.Another modified method is described for quantitative determination of HGPRT activity by means of radio thin-layer chromatography.Supported by the Deutsche Forschungsgemeinschaft, Bonn-Bad Godesberg. 相似文献
46.
Three pathogenic strains of Pseudomonas phaseolicola (strain 1 and 3 virulent and strain 5 weakly virulent) were tested for their toxic activity. All three strains produced detectable amounts of toxin in vitro. Cultural conditions and length of incubation greatly influenced toxin production. Maximum amount of toxin was produced at 20°C and pH 6.5. Glycerol served as the best carbon source and 1-cysteine as the best amino acid for toxin production. 相似文献
47.
As part of the development of carbon-coated prosthetic devices, the adhesion of thin carbon films to metallic substrates has been studied. The bond strength of carbon films about 5000 A thick on Ti-6A1-4V and stainless steel was measured in a pull test and found to be greater than 4700 psi. Auger electron spectroscopy showed a reactive film/substrate interface. The ultimate bond strength was found to be dependent on the substrate and the deposition parameters. 相似文献
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