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71.
为了评估法医学DNA数据库建设中涉及的59个Y-STR基因座的遗传多态性和法医学应用效能,通过AGCU Y SUPP PLUS试剂盒和AGCU Y37试剂盒检测374个广东汉族无关男性个体,将检测出的59个Y-STR基因座按照突变率的高低进行分类组合和统计分析。结果显示,59个Y-STR基因座联合运用在374个无关男性个体中检出了374个单倍型,其中44个中低突变Y-STR组合、15个高快突变Y-STR组合分别检出373和372个单倍型。59个Y-STR的基因多态性数值分布在0.055 1 (DYS645)~0.958 0 (DYF387S1 a/b)之间。结果表明,这59个Y-STR在广东汉族群体中均具有良好的多态性,按中低突变Y-STR组合和高快突变Y-STR组合研发新的检测体系可更好地满足法医实践的不同需求。 相似文献
72.
Pepper seed quality is sensitive to variations in climatic conditions during seed development, which might be associated with accumulation, distribution and leakage of mineral elements from the seeds. This was examined in hybrid seeds of sweet pepper (Capsicum annuum L. cv.‘Hazera’ 1195) in two experiments during two growing seasons. The mean daily temperature (day/night) and daily total radiation receipt during seed development were 27.9/23.2°C and 8.63 kW m?2 in the summer and 18.3/ 14.9°C and 3.18 kW m?2 in the winter, respectively. Seeds developed in the summer had lower percentage of seedling emergence and leaked a larger portion (45%) of their K content into the water medium than in winter‐developed seeds. Summer seeds accumulated more K and Cl, but less P, Mg, Ca and the weight ratio of linoleic acid to oleic acid was lower than in the winter seeds. The season did not significantly affect N, S and total fatty acids. The most abundant element on the seed coat surface was K in the summer and Ca in the winter seeds. The cotyledon and endosperm of the summer seeds contained relatively higher ratios of K and Ca and lower ratios of P and Mg than the winter seeds. Transportation of mineral nutrients appeared to be involved in the effect of heat and moisture stresses on emergence quality of the pepper seeds. 相似文献
73.
The crystal structures of Streptomyces diastaticus No. 7 strain M1033 xylose isomerase (SDXyI) have been analysed and refined at 0.19nm. The crystal space group is I222, with unit cell dimensions of a=9.884 ran, b=9.393nm and c=8.798nm. Based on the coordinates of the Streptomyces rubiginosus xylose isomerase (SRXyI), the initial model of SDXyl was built up by the dose packing analysing and R-factor searching and refined by PROLSQ to a final R-factor of 0.177 with the rms deviations of bond lengths and bond angles of 0.001 9nm and 2.1°, respectively. No significant global conformation change existed between SRXyI and SDXyI except the local conformation in the active site. 相似文献
74.
ZENG WenbingZHANG Weicheng XU ShiyuanYANG ZhizhongLIU ChunZHU DepingWEN QibinSHEN QixiangWANG Xianbin 《中国科学:生命科学英文版》1996,39(1):87-98
The mechanism of 13C-methacetin breath test is set forth clearly with the analysis of pharmacokinetics mode, and the measuring method of 13C-methacetin breath test and its clinical applications in the diagnosis of liver diseases are reported in detail. On the basis of comprehensive analysis of the clinical test data, the advanced diagnostic parameter S is of important significance for the application and development of breath test. 相似文献
75.
The mechanism of 13C-methacetin breath test is set forth clearly with the analysis of pharmacokinetics mode, and the measuring method of 13C-methacetin breath test and its clinical applications in the diagnosis of liver diseases are reported in detail. On the basis of comprehensive analysis of the clinical test data, the advanced diagnostic parameter S is of important significance for the application and development of breath test. 相似文献
76.
单爪螯蜂属二新种:膜翅目:螯蜂科;单爪螯蜂亚科 总被引:2,自引:2,他引:0
本文记述单爪螯蜂属二新种;梳垫单瓜螯蜂Anteon pectinarolium,sp.nov。和滑盾单爪螯蜂Anteon blanduscutum,sp.nov。新种的模式标本保存在浙江农业大学植物保护系。 相似文献
77.
鸡胚完整脑的光子发射和光激发光研究 总被引:2,自引:0,他引:2
利用自制的单光子记录系统,对离体的浸于DMEM培养液中的鸡胚的完整脑所进行的光子发射测量显示出整脑与培养液相比有光子发射.完整脑的光子发射强度与胚龄,鸡胚的健康状况和离体后脑组织的新鲜程度有关.在对完整脑的光激发光测量中观察到一种短寿命的延迟发光,它的衰减过程不服从指数衰减规律而表现出双曲线衰减行为.从生物光子发射归因于生物体内的非定位的相干性电磁场及Frohlish的生命系统中存在着长距离的相干性的理论,讨论了利用生物光子发射研究细胞间通讯、生物的调节及生物与环境关系的意义,以及所检测的光子发射与生物系统自身的相干性电磁场的关系,并提出应从环境对生物系统自身场的影响来理解所测的生物光子发射. 相似文献
78.
79.
关于徐州白云洞与南京汤山第1地点的哺乳动物化石 总被引:12,自引:0,他引:12
白云洞位于江苏省徐州市九里区九里山的白云寺内,产有中国鬣狗,三门马,李氏野猪,葛氏斑鹿,肿骨鹿等9个种类,其地质时代大体上与汤山第一地点或北京人动物群同时,为中更新世晚期。 相似文献
80.
YANG Jianbo WU Lijun LI Li WU JiadaoYU Zengliang XU Zhihong 《中国科学:生命科学英文版》1997,40(1):107-112
While M13mp18 double-stranded DNA was irradiated with ion beam, and transfected intoE. coli JM103, a decrease of transfecting activity was discovered. The lacZ- mutation frequency at 20% survival could reach (3.6–16.8) × 104, about 2, 3–10 times that of unirradiated M13DNA. Altogether, 27 IacZ-mutants were selected, 10 of which were used for sequencing. 7 of the sequenced mutants show base changes in 250-bp region
examined (the remaining 3 mutants probably have base changes outside the regions sequenced). 5 of the base-changed mutants
contain more than one mutational base sites (some of them even have 5–6 mutational base sites in 250-bp region examined);
this dense distribution of base changes in polysites has seldom been seen in X-rays, Y-rays or UV induced DNA mutations. Our
experiments also showed that the types of base changes include transitions(50%), transversions (45%) and deletion (5%); no
addition or duplication was observed. The transitions were mainly C→T and A→G; the transversions were mainly C→A and C→G.
The mutations involving cytosine residue (in the template strand) constitute about 60% of all the base changes observed. In
comparison with the surrounding sequences of mutational base sites, the base located between TG and CT is found to be easily
substituted. 相似文献