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41.
Variants of the anti-Müllerian hormone gene in a compound heterozygote with the persistent Müllerian duct syndrome and his family 总被引:25,自引:0,他引:25
Danièle Carré-Eusèbe Sandrine Imbeaud Madeleine Harbison Maria I. New Nathalie Josso Jean-Yves Picard 《Human genetics》1992,89(4):389-394
Summary The human genome contains a large number of interspersed simple repeat sequences that are variable in length and can therefore serve as highly informative, polymorphic markers. Typing procedures include conventional multilocus and single locus probing, and polymerase chain reaction aided analysis. We have identified simple sequences in a cosmid clone stemming from the human Y chromosome and consisting of (gata)n repeats. We have compared these with two equivalent simple repeat loci from chromosome 12. After amplifying the tandemly repeated motifs, we detected between four and eight different alleles at each of the three loci. Codominant inheritance of the alleles was established in family studies and the informativity of the simple repeat loci was determined by typing unrelated individuals. The polymorphisms are suitable for application in linkage studies, practical forensic case work, deficiency cases in paternity determination, and for studying ethnological questions. The mutational mechanisms that bring about changes in simple repeats located both on the autosomes and on the sex chromosomes, are discussed.Professor Dr. Otto Prokop (Humboldt-Universität Berlin) on the occasion of his 70th birthday 相似文献
42.
孤离大鼠左侧颈动脉窦,采用侧脑室(LCV)注射α_1受体阻断剂酚苄明(phenoxybenzam-ine PBZ,2μg/20μl)或α_2受体阻断剂育亨宾(yohimbine Y,2μg/20μl),以颈动脉窦内压(ISP)-平均动脉压(MAP)关系曲线及其有关参数为指标,研究和分析了中枢α受体对颈动脉窦反射的影响。将所得ISP和MAP经Logistic方程拟合,建立ISP-MAP关系曲线。结果如下:PBZ组,ISP-MAP关系曲线在高窦内压区明显上移;峰斜率、MAP变动范围明显减小;ISP-斜率关系曲线在15.96kPa处明显下移。Y组,ISP-MAP关系曲线在高窦内压区明显上移;峰斜率、MAP变动范围明显减小,阈压明显增大,ISP-斜率关系曲线在10.64、15.96kPa处明显下移。与PBZ组相比,Y组的峰斜率、MAP变动范围减小更明显。结果表明:中枢α_1或α_2受体阻断后,窦反射的敏感性明显降低,其中阻断α_2受体的作用尤为明显。 相似文献
43.
44.
桑树叶肉原生质体培养再生植株 总被引:11,自引:0,他引:11
近年来,木本植物原生质作诱导再生植株的研究越来越受到国内外学者关注。但在林木树种中,迄今成功的种类仍然不多,在文 相似文献
45.
S Lyonnet A Pelet G Royer O Delrieu F Serville B le Marec A Gruensteudel R A Pfeiffer M L Briard C Dubay 《Genomics》1992,14(2):508-510
We report the study of five independent X-linked hydrocephalus (HSAS1) families with polymorphic DNA markers of the Xq28 region. A total of 58 individuals, including 7 living affected males and 22 obligate carriers, have been studied. Maximum lod score was 7.21 at theta = 2.40% for DXS52 (St14-1). A single recombination event was observed between this marker and the HSAS1 locus. Other markers studied were DXS296 (Z = 2.02 at theta = 2.5%), DXS304 (Z = 4.37 at theta = 7.8%), DXS74 (Z = 3.50 at theta = 0%), DXS15 (Z = 1.96 at theta = 5.7%), DXS134 (Z = 3.31 at theta = 0%), and F8C (Z = 5.79 at theta = 0%). These data confirm the localization of the HSAS1 gene to Xq28 and provide evidence for genetic homogeneity of this syndrome. In addition, examination of two obligate recombinant meioses along with multipoint linkage analysis supports the distal localization of the HSAS1 locus with respect to the DXS52 cluster. These observations are of potential interest for future studies aimed at HSAS1 gene characterization. 相似文献
46.
The results of a previous pharmacokinetic study of disopyramide (DP) enantiomers in humans suggested that DP and/or mono-N-desisopropyldisopyramide (MND) may show stereoselective extrarenal elimination. Thus, the present study investigates the biliary elimination of DP and MND enantiomers in three patients who had undergone cholecystectomy for cholelithiasis. DP and MND enantiomers displayed biliary elimination. In both subjects, this elimination pathway showed the same characteristics: (1) biliary elimination of DP and MND was stereoselective, (2) the stereoselectivity was opposite to that observed for the metabolic and renal elimination pathways, i.e., the elimination of the (-)-(R)-enantiomer was higher than that of the (+)-(S)-enantiomer, and (3) biliary elimination of MND was higher than that of DP, for both enantiomers. Estimates of the relative contribution of the biliary clearance in the total clearance of DP and MND indicated that this elimination pathway was secondary, especially for DP. The biliary clearance (expressed as % of total clearance) was 1.9 to 4.0% for (-)-(R)-DP, 1.2 to 1.7% for (+)-(S)-DP, 7.8 to 22.9% for (-)-(R)-MND, and 5.2 to 10.5% for (+)-(S)-MND. 相似文献
47.
1-Aminocyclopropane-l-carboxylate (ACC) synthase from applefruits was purified over 5,000-fold by conventional column chromatography.By immunizing mice with this partially purified enzyme preparation,8 hybridoma lines producing monoclonal antibodies against appleACC synthase were isolated. While all 8 clones immunoprecipitatednative ACC synthase, only two clones recognized the putative(48 kDa) ACC synthase on Western blots. When a partially purifiedACC synthase preparation was incubated with S-adenosyl-L-[carboxyl-14C]methionine(AdoMet), only one radioactive protein of 48 kDa was detectedon sodium dodecyl sulfate-poly-acrylamide gel electrophoresis.This radioactive protein was specifically immunoprecipitatedby the monoclonal antibodies, indicating that apple ACC synthaseis specifically radiolabeled by its substrate AdoMet, as istomato ACC synthase. Thus, the monoclonal antibodies recognizedboth native and AdoMet-inactivated forms of ACC synthase. Whilethese antibodies failed to im-munoprecipitate ACC synthase isolatedfrom ripe tomato fruits, ripe avocado fruits or auxin-treatedmungbean hypocotyls, they were effective in immunoprecipitatingthe enzyme isolated from ripe pear fruits. (Received August 11, 1990; Accepted October 17, 1990) 相似文献
48.
Cell proliferation and cellular differentiation are often thought of as opposing phenomena. The molecular mechanisms by which steroid, retinoid and thyroid hormones inhibit cellular proliferation and by which growth factors stimulate this process are poorly understood. We discuss recent evidence suggesting that these two signal transduction pathways converge through a process referred to as 'cross-coupling', which involves a possible interaction between steroid hormone receptors and the c-Jun oncoprotein. 相似文献
49.
50.
用免疫细胞化学技术观察了单眼剥夺后金黄地鼠视觉中枢GABA神经元分布的变化。结果表明:单眼剥夺后,金黄地鼠视皮层和上丘的GABA阳性神经元暂时性增多,但剥夺后六个月,其数目显著减少。在单眼剥夺前和剥夺后侧膝体中GABA阳性神经元数目没有明显差异。剥夺眼对侧视皮层GABA阳性神经元数比剥夺眼同侧视皮层GABA神经元数目少。单眼剥夺后视觉中枢GABA神经元类型及形态与剥夺前没有差别。晚期单眼剥夺也能引起视觉中枢GABA神经元数量和分布的变化。以上结果表明,单眼剥夺后视觉中枢抑制神经元的结构发生了变化。 相似文献