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21.
Summary A kinetic study of hormonal inactivation in the presence of sodium thioglycolate was carried out using the rat uterus bioassay. In all cases we observed a total inactivation of the hormonal activities, whether the uterine horn is in the presence or not of magnesium. The hormones under consideration divide into 2 groups: the arginine-vasotocin group (rapidly inactivated), and the ichtyotocin and oxytocin group (more slowly inactivated). But, in all cases the rate of inactivation is linear.

Avec la collaboration technique de Mr.G. Hoeltzel.  相似文献   
22.
Bardet-Biedl syndrome (BBS) is a genetically heterogeneous ciliopathy. Although nine BBS genes have been cloned, they explain only 40-50% of the total mutational load. Here we report a major new BBS locus, BBS10, that encodes a previously unknown, rapidly evolving vertebrate-specific chaperonin-like protein. We found BBS10 to be mutated in about 20% of an unselected cohort of families of various ethnic origins, including some families with mutations in other BBS genes, consistent with oligogenic inheritance. In zebrafish, mild suppression of bbs10 exacerbated the phenotypes of other bbs morphants.  相似文献   
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基于藏文La格(??????)例句的自动分类在藏语自然语言处理领域的重要性,根据藏文La格的用法和添接规则,在对藏文La格例句进行分类并定义分类概念的基础上,提出一种融合双通道音节特征的藏文La格例句自动分类模型.该模型首先使用word2vec和Glove构建双通道藏文音节嵌入,分别在每路卷积中融合双通道音节特征,丰富...  相似文献   
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The human X and Y chromosomes evolved from an ordinary pair of autosomes during the past 200-300 million years. The human MSY (male-specific region of Y chromosome) retains only three percent of the ancestral autosomes' genes owing to genetic decay. This evolutionary decay was driven by a series of five 'stratification' events. Each event suppressed X-Y crossing over within a chromosome segment or 'stratum', incorporated that segment into the MSY and subjected its genes to the erosive forces that attend the absence of crossing over. The last of these events occurred 30 million years ago, 5 million years before the human and Old World monkey lineages diverged. Although speculation abounds regarding ongoing decay and looming extinction of the human Y chromosome, remarkably little is known about how many MSY genes were lost in the human lineage in the 25 million years that have followed its separation from the Old World monkey lineage. To investigate this question, we sequenced the MSY of the rhesus macaque, an Old World monkey, and compared it to the human MSY. We discovered that during the last 25 million years MSY gene loss in the human lineage was limited to the youngest stratum (stratum 5), which comprises three percent of the human MSY. In the older strata, which collectively comprise the bulk of the human MSY, gene loss evidently ceased more than 25 million years ago. Likewise, the rhesus MSY has not lost any older genes (from strata 1-4) during the past 25 million years, despite its major structural differences to the human MSY. The rhesus MSY is simpler, with few amplified gene families or palindromes that might enable intrachromosomal recombination and repair. We present an empirical reconstruction of human MSY evolution in which each stratum transitioned from rapid, exponential loss of ancestral genes to strict conservation through purifying selection.  相似文献   
25.
Summary The modification described allows the homogeneization of only one organ in a very small liquid medium amount. It permits 4 operations with the same tube, i.e. grinding, water bath, centrifugation and direct reinjection of the material treated in Pedersen micropipettes.  相似文献   
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佘堃  杨异 《实验科学与技术》2009,7(2):85-87,140
以计算机为核心的多媒体教学在我国高校已经蓬勃兴起。文章针对现在教育面临的新形式,进行了高校计算机课程的教学与改革探讨。针对电子科技大学已经开展的多媒体式、专周式教学,就如何培养学生技能、提高动手能力,为最后的就业打下坚实基础提出了一些想法和建议。并对一些教学方法的效果进行了统计分析,通过分析和探讨,结合教学实际,提出了一些措施与建议,希望对探讨高校计算机专业教学、学习、就业有所帮助。  相似文献   
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