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81.
本文采用EBV(Epstein?Barr Virus)上清液转化B淋巴细胞,并加入环胞霉素A(Cyclosporine A)抑制T淋巴细胞,成功地对中国东北地区鄂温克族、鄂伦春族及达斡尔族的部分个体建立了永生细胞系,其中鄂温克族49株,鄂伦春族40株,达斡尔族51株,总计140株。永久保存我国特有民族的基因组,为分析其遗传学差异奠定了基础。 Abstract:The immortal lymphoblastoid cell lines were established by EBV transformation of B cells and addition of cyclosporin A to inhabit the activity of T cells.In the present study ,140 immortal cell lines of the Ewenki,the Oroqen and the Daur ethnic groups in the Northeast China were established .This is an important part of the research of human genome diversity for the exploration of the origin and progression of different ethnic groups ,and also provide enough research materials for further studies.  相似文献   
82.
水稻是最重要的粮食作物之一,世界上大约有一半的人口以水稻为主要粮食.作为基因组研究的模式植物,水稻基因组的测序工作已在世界范围内展开.此项研究工作不仅能破译水稻全基因组序列,还将有助于了解其他禾本科植物的基因组信息.本文对水稻基因组测序工作进展作一综述。 Abstract:Because of the importamce of rice as the staple food source for over half of the world population and since rice is a leading model plant for genomic studies,an international effort has now begun to sequence the rice genome.This project eventually will reveal all of the genomic sequence information of rice and be an indispensable aid in understanding the genomics of other grass species.In this paper,the development and research progress in sequencing of rice genome are reviewed.  相似文献   
83.
84.
利用RNA原位杂交技术, 对水稻受精前后雌蕊组织切片进行磷酸化酶基因表达的定位。结果显示, 磷酸化酶mRNA在柱头、花柱、子房壁以及维管束中大量表达, 而胚珠中除合点部位外表达很弱。受精前后的胚囊中各细胞磷酸化酶mRNA表达也很弱, 并且没有明显的时空变化。在积累淀粉的胚乳细胞中磷酸化酶mRNA大量分布。原胚中的磷酸化酶mRNA表达较弱, 到分化胚积累过渡性淀粉时才显著增加。本文首次对磷酸化酶mRNA在植物雌性器官发育过程中的时空分布动态作了初步研究。 Abstract:Phosphorylase gene expression was localized in tissue sections of rice pistils before and after fertilization byin situRNA hybridization. Phosphorylase mRNA was substantially expressed in the stigma, style, ovary wall and vascular bundle, but weakly in ovular tissues except chalazal portion. It was weakly expressed and did not show temporal and spatial changes in embryo sacs before and after fertilization. A great quantity of phosphorylase mRNA was distributed in endosperm cells accumulating starch grains. Phosphorylase mRNA was less in proembryos, but significantly increased in differentiation embryos accumulating transition starch. This report is, for the first time, a tentative investigation on the temporal and spatial expression patterns of phosphorylase mRNA in plant female organ development.  相似文献   
85.
中国春小麦株高、育性近等基因系的建立及应用   总被引:4,自引:0,他引:4  
以矮败小麦和中国春小麦为材料,经过杂交和连续回交,得到了中国春小麦遗传背景的分别表现矮秆不育、矮秆可育、高秆不育、高秆可育的近等基因系。根据近等基因系各成员系的株高表现,计算出矮秆基因Rht10的降秆强度是69.8%。借助于赤霉酸处理,在幼芽期就可分出矮败中国春小麦后代的不育株与可育株。 Abstract: Use Dwarfing Male-sterile Wheat and cv. Chinese Spring as parents, after cross and continuously back cross, the isogenic lines with Chinese Spring background were developed. These lines include dwarfing male-sterile line, dwarfing fertile line, tall male-sterile line and tall fertile line. The dwarfing intensity of gene Rht10 was calculated to be 69.8% according the differences between the isogenic lines. Treated with GA3solution, the male-sterile and fertile plants in Chinese Spring Dwarfing Male-sterile Wheat can be identified clearly when they are seedlings.  相似文献   
86.
从土壤中筛选到一株能够拆分外消旋的硫辛酸中间体6-羟基-8-氯辛酸乙酯的微生物菌株T4,并对其拆分反应条件进行了优化,确定了最适反应温度为30℃,最适pH为7.0,最适摇床转速为170r/min,确定了有效表面活性剂为CTAB,在此优化条件下反应8h,得到(R)-6-羟基-8-氯辛酸乙酯的对映体过量值(e.e.)为92.8%,产率为26.3%。该研究为(R)-硫辛酸的制备提供了一条可行的途径。  相似文献   
87.
遗传参数不同估计方法的比较   总被引:6,自引:0,他引:6  
利用模拟方法比较了5种方差组分估计方法(ANOVA,Henderson-Ⅲ,MLMT,R EMLMT和MIVQUE)对遗传参数的估计效果。结果表明:REMLMT法在各种情况下均能得到较好的参数估值,估计的准确度相对较高;ANOVA方法在小群体和不均衡资料情况下估计效果最差。同时,群体含量和结构能影响各种方法的估计效果, 群体含量较小或资料来源的公畜数太少,将导致遗传参数的估计误差增大,准确性降低。 Abstract:Five methods for estimating components of (Co) variance,including ANOVA,Henderson-III,MLMT,REMLMT and MIVQUE were compared using computer simulation.The results showed that REMLMT could obtain more accurate estimates for all data sets,while the estimates obtained by ANOVA always had greater deviations from the true values,especial for small and well-unbalanced data sets.Also,the effects of estimation were dependent on structure of population size,accuracy of estimates would be decreased when number of sires was too few or data contained small number of animals.  相似文献   
88.
PCR方法用于奶牛早期胚胎的性别鉴定   总被引:8,自引:0,他引:8  
根据牛Y染色体上的特异DNA序列合成一对引物, 通过PCR反应对奶牛早期胚胎进行性别鉴定。预测性别与移植胚胎产犊的实际性别相符率为80%。 Abstract:We have obtained the specific DNA segment from the bovine Y-chromosome and used it to design a pair of primer.The sex of embryos at the preimplantation stage have determined by using the polymerase chain reaction.10 months after uterine transfer showed that the rate of accuracy is 80%.  相似文献   
89.
利用PCR技术和复合电泳银染技术检测奶牛和肉牛BM2113、BM1862、BMc701、BM2934、TGLA122、BM720等6个STR基因座的多态性分布,并计算该6个基因座的基因频率(Pi)、个体鉴别力(DP)、杂合度(H)、多态信息含量(PIC)、和非父排除概率(PE)。结果显示:6个STR基因座的基因型分布符合Hardy-Weinberg平衡,奶牛中6个STR基因座中BM2113 基因座的DP、H和PIC最高,TGLA122基因座的PE最高。 6个STR基因座的累积个体鉴别力 (CDP)为 0.99997 ,累积非父排除能力(CPE)为 0.98827 。肉牛中6个STR基因座中BM1862 基因座的DP、H、PIC、PE都是最高,6个STR基因座的累积个体鉴别力(CDP)为 0.99999,累积非父排除能力(CPE)为 0.99578 。结果表明,6个STR基因座可用于牛的遗传连锁分析、个体识别和亲子鉴定等研究领域。Abstract:The polymorphism distributions of six STR loci,BM2113,BM1862,BMc701,BM2934,TGLA122,and BM720 were detected in cattle by Polymerase Chain Reaction and multiplex gel electrophoresis followed by silver staining. Gene frequency (Pi),power of discrimination (DP), heterozygosity (H), polymorphism information content (PIC) and probability of paternity exclusion (PE) were calculated.All loci obey Hardy-Weinberg equilibrium. DP, H and PIC of BM2113 locus, and PE of TGLA122 locus are the biggest among six STR loci in Holstein Friesian. Cumulate DP of six STR loci is 0.99997, Cumulate PE of six STR loci is 0.98827. DP, H, PIC and PE of BM1862 loci are the biggest among six STR loci in beef. Cumulate DP of six STR loci is 0.99999, Cumulate PE of six STR loci is 0.99578. These results showed that the six STR loci could be used as linkage analysis, individual identification and paternity test in cattle.  相似文献   
90.
Human embryonic stem cells(hESCs)have been successfully differentiated into hematopoietic progenitor cells with colony formation capacity and further into various kinds of blood cells including erythrocytes,megakaryocytes,neutrophils,nature killer cells and T lymphocytes[1 7].Nevertheless,the differentiation efficiency is extremely low.  相似文献   
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