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181.
高粱九个性状遗传参数的分析   总被引:1,自引:0,他引:1  
1991─1992连续两年,在水、旱地两种环境条件下,对20个品杂种,9个性状进行了3个遗传参数的分析。从遗传进度的估算中确定了较高增量的性状。在遗传相关的分析中,又得出14对性状遗传相关系数较高,表现型相关系数水、旱地都达到显著水准。但在相关遗传进度的估算中,其增量幅度旱地明显地小于水地,这说明旱地培育高产品种的困难较大。通过对12 4个指数项目的分析,提出了水、旱地育种各自应采用的较好的选择方案。  相似文献   
182.
云南苗族人红细胞EsD、PGM1和GLOI分布的调查   总被引:1,自引:0,他引:1  
采用EsD-PGM1-GLOI同步电泳分型法,对云南省屏边苗族自治县138例苗族人红细胞EsD、PGM1和GLOI作了分型调查,计算出这3种红细胞同功酶的基因频率是:EsD1 0.6014、PGM11 0.6304(PGM61 0.0109),GLO1 0.1123;根据这3种同功酶的表型频率计算出DP值分别为EsD 0.6206 ,PGM1 0.6315,GLOI 0.3377,累积DP值0.9074。  相似文献   
183.
诱发小麦花药愈伤组织及其再生植株抗盐性变异的研究   总被引:30,自引:3,他引:27  
不同基因型小麦花药愈伤组织对化学诱变剂的敏感性不同。选用对诱变剂敏感的类型,经EMS(甲基磺酸乙酯)诱变可以产生耐盐变异。实验获得的耐盐变异株, 离开盐胁迫3代后,经盐池鉴定后代中有52.9%的品系达到一级耐盐,表现了一定的遗传稳定性。耐盐品系的结实率也逐渐得到恢复,达到92.4%。利用其高代材料进行耐盐性的遗传分析结果表明,小麦的耐盐性不仅受核基因的控制,也受细胞质因子的影响。经酸性聚丙烯酰胺凝胶电泳分析,发现耐盐突变体特有的Rf值为0.19的醇溶蛋白能稳定遗传。 Abstract:The study discovered that the sensibilities of anther calli in different wheat genetypes to chemical mutagenic agent were different.The mutation-sensitive type might generate salt-tolerant variation after mutagenizing with EMS.The fourth generation of salt-tolerant plants which were planted for three generations in usual soil expressed tolerance stability after planting in the salt pond of a 0.45% salt concentration,52.9% of the lines in the offspring belonged to first grade of salt-tolerance,showing that the salt-tolerant variant had a certain stability.The fertility of salt-tolerant lines was gradually recovered and reached 92.4%.The high generation materials were used for genetic analysis of the salt-tolerance.The results indicated that the wheat salt-tolerant trait is not only controlled by nuclear gene,but also effected by cytoplasmic factor.In addition,A-PAGE(Acid-Polyacrylamide gel electrophoresis)discovered that the salt-resistant mutant had a unique gliadin band with a Rf value of 0.19,and that this unique band was stable inherited.  相似文献   
184.
云南汉族人群D17S30位点扩增片段长度多态性A   总被引:4,自引:0,他引:4  
应用PCR技术和小型聚丙烯酰胺凝胶电泳银染法, 对云南汉族人群D17S30位点扩增片段长度多态性进行了分析。在被检的105名无关个体中,共检出12个等位基因,41种基因型。等位基因频率范围在0.0048-0.2190之间,杂合度为83.81%,DP值为0.9647。观察的基因型分布符合Hardy-Weinber g定律。 Abstract:A study on amplified fragment length polymorphism(Amp-FLP)at locus D17S30 in Han nationality of Yunnan was carried out by using PCR followed by a high-resolution PAGE technique and silver staining.In a sample of 105 unrelated individuals,a total 12 different alleles and 41 genotypes were detected.The heterozygosity was 83.81% and the probability of discrimination(DP) was 0.9647.The distribution of observed genotypes obeyed the Hardy-Weinberg equilibrium.  相似文献   
185.
186.
为了研究对烟草中烟碱与绿原酸的快速生物降解,筛选了能有效降解烟草中烟碱与绿原酸的链霉菌Z6菌株与Z8菌株,考察了Z6和Z8菌株在不同培养基上的培养特征,探讨了所选菌株对烟碱与绿原酸的降解特性。实验结果表明,Z8链霉菌在烟草固体培养基中培养48h后,对培养基中烟碱的降解率达到83.9%;培养72h后,对烟碱的降解率可达到93.7%,此时烟草中的烟碱含量降低到0.38mg/g,达到了欧盟条例的无害化标准。Z6菌对绿原酸的降解程度较高,培养48h后,对绿原酸的降解率为57.1%;培养72h后,降解率可达到67.5%.  相似文献   
187.
李雪梅  马德花  赵淑萍 《生物磁学》2008,(12):2442-2444
目的:研究转化生长因子(TGF-β1)及其Ⅰ型受体(TβRI)在子宫内膜癌组织中的表达及其临床意义。方法:采用RT-PCR方法检测36例子宫内膜癌及31例正常子宫内膜组织中TGF-β1及TβRI基因的表达水平,分析其与临床病理参数之间的关系。结果:子宫内膜癌组织中TGF-β1mRNA的表达明显高于正常组织(P〈0.05),而TβRI mRNA的表达水平明显低于正常内膜组织(P〈0.05)。TGF-β1mRNA及TβRImRNA在子宫内膜癌中的表达均与肿瘤的临床分期、组织学分级、肌层浸润深度、淋巴结转移呈显著性相关(P〈0.05),差别有统计学意义。结论:TGF-β1及其Ⅰ型受体TβRI在子宫内膜癌的发生、发展中可能起重要作用,检测TGF-β1及TβRI对评价子宫内膜癌的转移及预后有重要价值。  相似文献   
188.
Although previous studies showed that the principal oncoprotein encoded by Epstein-Barr virus, latentmembrane protein 1 (LMP1) 5 could induce the nasopharyngeal carcinoma cells in G_2/M phase increased, littleis known about the target molecules and mechanisms. The present study demonstrated that LMP1 couldinduce the accumulation of p53 protein and upregulate its transactivity in a dose dependent manner, whichresulted in the decrease of the kinase activity of cdc2/cyclin B complex and inducing arrest at G2/M phasethrough the activation of NF-κB and AP-1 signaling pathways, and the effect of NF-κB was more obviousthan that of AP-1. This study provided some significant evidence for further elucidating the molecularmechanisms that LMP1 had effects on the surveillance mechanism of cell cycle and promoting the survivalof transformed cells and tumorigenesis.  相似文献   
189.
Well-spread meiotic pachytene bivalents were obtained by using the prolonged hypotonic treatment combined with high chloroform Carnory's fixative solution from cells of the testes of domestic pigs. Comparison in the division index and length of pachytene bivalents with metaphase chromosomes showed that those of the former are 5 times higher and 3.42(1.87-5.98) times longer than those of the latter. Comparative studies on chromomere maps of bivalents and mitotic chromosomal G-bands were conducted by using the chromosome 12 as a example. Sex vesicle and various shapes of synaptic sex chromosomes have been observed. Two-color PRimed IN Situ (PRINS) labeling has been conducted successfully on pachytene bivalents of pigs.  相似文献   
190.
p28, a 28kD protein from toad (Bufo bufo gargarizans) oocytes, was identified by using p13sucl-agarose affinity chromatography. Sequence homology analysis of the full-length cDNA of p28 (Gene Bank accession number: AF 314091) indicated that it encodes a protein containing 224 amino-acids with about 55% identities and more than 70% positives to human, rat or mouse UCH-L1, and contains homological functional domains of UCH family. Anti-p28 monoclonal antibody, on injecting into the oocytes, could inhibit the progesterone-induced resumption of meiotic division in a dose-dependent manner. The recombinant protein p28 showed similar SDS/PAGE behaviors to the native one, and promoted ubiquitin ethyl ester hydrolysis, a classical catalytic reaction for ubiquitin carboxyl terminal hydrolases (UCHs). The results in this paper reveal that a novel protein, p28, exists in the toad oocytes, is a UCH L1 homolog, was engaged in the process of progesterone-induced oocyte maturation possibly through an involvement in prot  相似文献   
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