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皖南汉族的趾纹研究 总被引:3,自引:0,他引:3
本文对皖南地区520例汉族大学生的趾纹进行了调查分析,计算出了各型趾纹频率、趾纹组合、趾嵴纹计数等项参数。比较了不同性别、不同侧别和不同人种间的差异,分析了趾纹类型和趾嵴纹计数在各趾的分布特点,并对差异的原因进行了讨论。Abstract: The authors inverstigated and analysed the toe prints of 520 cases of good healthy students in Wannan area of Aahui, and calculated the frequency of various toe patterns, combinations of toe patterns, toe ridge counts (TRC) and so on. The differences between sexes, sides and reces were compared. The distributive character of toe patterns and toe ridge count on every toe were analysed. The different cause were discussed. 相似文献
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Largepterosaurwithamaximumwingspanofmorethan5metres.Theskullislowerandlonger,withoutmiddlecrestorsupraoccipita1crest.ThenasaIandpre-orbita1fenestraareconfluentcompletely,andoccupyaboutha1foftheskulI1ength.Thetoothlessbeakisslenderandpointed.The1ongneckiscomposedbyse-venslendercervicalvertebrae.Thenotariumconsistsofsixco-ossifiedanteriordorsalvertebrae-ThetaiIisextremlyshort.lthassixpairsof"A"shapegastralia.Theanteriorlimbsarestrong;thehumerusarethickandshort;thewing-metacarpalbonearelongert… 相似文献
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本文提出“中国人体细胞G式显带染色体的鉴别及模式图”。 (一)显带方法 1.湖南医学院医学遗传研究室所用的方法(1973):用外周血和骨髓标本按常规方法培养和滴制染色体玻片标本后,立即置70一80℃烤箱内烤2一3小时,关闭烤箱,让其自然冷却后,按下列程序进行显带:(1)在无菌条件下,用0.8,%NaCI溶液配制0.25多胰蛋白酶溶液,玻璃滤菌器过滤,冰箱保存。(2)将上述0.25铸胰蛋白酶溶液倒人染色缸中,用1 MNaOH调pH至7.0左右,用水浴加温至37℃。(3)将玻片标本投人胰蛋白酶溶液中,不断轻轻地摆动2一3分钟左右。(D取出玻片标本,直立于吸水纸上数秒钟,… 相似文献
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There is a growing interest in developing experimental methods for tracking the developmental cell lineages of a complex organism.The recently developed CRISPR/Cas9-based barcoding method is,although highly promising,difficult to scale up because it relies on exogenous barcoding sequences that are engineered into the genome.In this study,we characterized 78 high-quality endogenous sites in the zebrafish genome that can be used as CRISPR/Cas9-based barcoding sites.The 78 sites are all highly expressed in most of the cell types according to single-cell RNA sequencing(scRNA-seq)data.Hence,the barcoding information of the 78 endogenous sites is recovered by the available scRNA-seq platforms,enabling simultaneous characterization of cell type and cell lineage information. 相似文献
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During the differentiation and maturation of erythrocytes, the surface molecules of erythrocytes are gradually expressed and stabilized. These molecules are to be antigenic in addition to their functions of maintaining cell membrane structural stability, material transport and exchange of cells and signal transmission between cells. The antigenic molecules on the erythrocyte surface are called erythrocyte blood group antigens. The blood group antigens and their corresponding blood group antibodies in vivo are important indicators for clinical blood transfusion and organ transplantation, and also form the basis for research on blood group related diseases. Three hundred and sixty-eight erythrocyte blood group antigens have been confirmed so far, which are classified into 39 blood group systems, 5 blood group collections and 2 blood group series. Based on the diversity of blood group antigens and their composition of glycolipids, glycoproteins and other molecules, this study mainly reviews the classification, molecular structure, antibody response and gene regulation of blood group antigens, and explains the main reasons for the diversity of blood group antigens. 相似文献