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181.
LI DeSheng~ CUI HengMin~ WANG ChengDong~ LING ShanShan~ HUANG Zhi~ & ZHANG HeMin* China Research Conservation Center for the Giant P a Ya’an China Medical College of Animal Sichuan Agricultural University Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education State Conservation Center for Gene Re- sources of Endangered Wildlife Hangzhou 《科学通报(英文版)》2011,56(24):2559-2564
Captive populations provide a precious genetic resource for endangered animals and a source of individuals for reintroduction to depleted habitats. Therefore, accuracy in determining paternity is of vital importance for managing captive populations and in selecting representative individuals of known genetic characteristics for release. In this study, we established a fast and effective method to conduct paternity testing for captive giant pandas in the Wolong population. This technique uses two highly poly... 相似文献
182.
R/S构型标记法标记含手性碳原子的构型是有机化学教学中的重点和难点之一.作者在教学过程中,将自身作为模型,用自己的头和展开的左手、右手使它们互成120度夹角,头、左手和右手分别表示手性碳除最小基团外相应位置的其余三基团,然后再判断三基团大→中→小的顺序,顺时针为R构型,逆时针为S构型.这种方法可以简便、快捷、准确地标记手性碳的构型,学生也最容易接受和掌握,在教学中取得了很好的效果. 相似文献
183.
Feng Zongyun 《高技术通讯(英文版)》2005,11(3):320-324
106 aeeessions of Tibetan wild barley, including 50 accessions of the two-rowed wiht barley Hordeum vulgare ssp. sopntaneum (HS), 27 accessions of the six-rowed bottle-shaped wild barley H. lagunculiforme (HL) and 29 accessions of the six-rowed wiht barley H. agriocrithon (HA) that separately represent different agrigeographical regions of Tibet, were used to study the genetic diversity and genetie differentiation using SSR markers selected from seven barley linkage groups. 229 allelic variants were identified with an average of 7.6 alleles/locus. The average of total number of alleles per locus in HA (6.4) is much higher than that in HS (3.9) and HL (3.4). The genetie diversity and its standard deviation among the three subspecies were in the order of HS〉HL〉HA. Very significant genetic differentiation was observed among the three subspecies of wild barley. Comparisons of the results fiom this and previous studies showed a strong Oriental-Occidental differentiation of barley, and that Shannan region of Tibet might be the center of origin of the Tibetan two-rowed wild barley, thus supporting not only the hypothesis of a mono-phyletie origin of cultivated barley but also the proposition that the Tibetan two-rowed wild barley as ultimate progenitor of Chinese cultivated barley. 相似文献
184.
The genetic structure and variation of the artificial meio- gynogenetic population and common population of barfin flounder
(Verasper moseri) were analyzed using eight microsatellite markers. A total of 29 alleles were detected, of which 23 alleles were in the artificial
gynogenetic population while 29 alleles were in the control group. The average observed heterozygosity (H
O) of eight loci in the control group (0.526 8) was several times higher than that (0.185 8) in the gynogenetic population.
The results indicate that the genetic diversity of the control group was much higher than that of the gynogenetic population
of barfin flounder (Verasper moseri). Most loci significantly deviated from Hardy-Weinberg equilibrium (HWE) after Bonferroni correction (p < 0.005 56) in the gynogenetic population, while four loci deviated from HWE in the control group. The coefficient of gene
differentiation (G
ST) was 0.131 0, and the genetic distance was 0.171 8 between the two populations, suggesting a significant genetic differentiation
between the two populations.
Biography: MA Hongyu (1979–), male, Ph. D. candidate, research direction: marine biotechnology and molecular genetics. 相似文献
185.
【目的】确定通过杂交和突变选育出的条斑紫菜(Pyropia yezoensis)栽培品系的遗传多样性。【方法】采用简单重复序列区间(Inter simple sequence repeat,ISSR)、扩增片段长度多态性(Amplified fragment length polymorphism,AFLP)和随机扩增多态性DNA(Random amplified polymorphism DNA,RAPD)等3种分子标记对条斑紫菜不同栽培品系进行遗传多样性分析。【结果】3种分子标记的多态性比率分别为38.10%、38.95%和61.75%;所表现出来的不同栽培品系间遗传距离分别为0.1785,0.1029和0.2845;3种分子标记聚类结果并不完全一致,但可以看出Y-0602、Y-HA01和Y-H001总是聚类在一起,而Y-DL02倾向于单独聚为一支。【结论】通过诱变和杂交所选育的品系,在遗传角度上仍然属于条斑紫菜,但已形成不同栽培品系,具有一定的遗传多样性。 相似文献
186.
通过研究MDA、电解质渗出量和Q2^-这3个损伤性指标,初步探讨了通过生物标志物来管理生物除磷体系的可行性。结果表明,MDA、电解质渗出量和Q.^-这3个指标中,利用SOD电极在线检测Q.^-的变化来管理除磷体系最为简便。从Q.^-的变化规律得出当体系由好氧交替到厌氧时。前90min对释放磷尤为重要,即受氧胁迫时,系统产生O2.^-浓度不能高于0.025mmol/g,否则磷的释放不会增加,进而影响系统的除磷效果。因此,可以通过在线监测O2.^-的浓度变化来动态管理除磷体系。 相似文献
187.
C. Hanski T. Zimmer R. Gossrau W. Reutter 《Cellular and molecular life sciences : CMLS》1986,42(7):826-828
Summary The specific activity of dipeptidyl peptidase IV (DPPIV E.C. 3.4.14.-) in the plasma membrane of Morris hepatoma 9121 or hepatoma 7777 was 3.5% and 2.9%, respectively, of that in the plasma membrane of rat liver. The enzyme activity in the serum of hepatoma-bearing rats was 141% (hepatoma 91219) and 162% (hepatoma 7777) of the normal value. cytochemical investigation showed that the DPP IV activity was almost completely absent from the hepatoma cell plasma membrane and was not sequestered within these cells. Indirect immunofluorescence staining with a polyclonal antibody directed against DPP IV indicated that the loss of activity was due to the absence of DPP IV molecules in the plasma membrane. The possibility that the enzyme is transferred from the membrane into the serum as a result of structural alterations is discussed. 相似文献
188.
The genetic diversity of Gaozhou wild rice analyzed by SSR 总被引:5,自引:0,他引:5
LI Chen PAN Dajian MAO Xingxue TU Congyong ZHOU Hanqin FAN Zhilan LI Xiaofang 《科学通报(英文版)》2006,51(5):562-572
LOCATED AT 21°42′34″―22°18′48″N AND 110°36′48″― 111°22′45″E IN THE TRANSITION REGION FROM SOUTH SUB- TROPICS TO NORTH SUBTROPICS, GAOZHOU WILD RICE (GWR) IS COMMON WILD RICE (ORYZA RUFIPOGON GRIFF.) AND THE WIDEST WILD RICE POPULATION IN GUA 相似文献
189.
红麻微卫星DNA的分离 总被引:1,自引:0,他引:1
分别采用RAPD、锚定PCR和磁珠捕获等3种方法富集含微卫星序列的红麻基因组DNA片段,并连接到pMD18-T载体,构建基因组文库.然后以通用引物M13F,M13R和根据微卫星核心序列所设计的引物[VRV(CT)12或VRV(TG)12],用PCR方法直接对文库筛选,并将获得的阳性克隆进行测序.分别从RAPD,锚定PCR和磁珠捕获3种富集方法构建的基因组文库中获得6,23,19个微卫星位点. 相似文献
190.
提出了以区间分子标记定位QTL时,以分子标记各种类型的性状密度函数进行极大似然估计,进而获得LOD值的极大值,达到准确定位QTL的结果,并与原方法进行了比较。结果表明,新方法所得LOD的数字表达式更简单,并且可以看出样本客量n和分子标记的密度r对于maxELOD值的估计有很大影响。 相似文献