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991.
992.
2003~2005年进行了冬春小麦42个水旱地品种的比较试验,运用灰色关联综合评价方法,筛选出西吉县丰产抗条锈病品种:冬小麦水地品种静冬9717、静冬941、静冬9718,旱地品种8802、陇原935、陇原992综合性状较好且抗条锈病;春小麦水地品种宁春4号、802-15、定丰806;旱地品种93-163-6、陇春8139-2综合性状较优,除宁春4号较易感条锈病外,其它品种均抗锈病。抗病品种比感病品种提高产量15.40%~61.12%。建议今后在西吉县大面积推广种植这些品种时,水浇地要特别注意宁春4号品种的条锈病预测及防治工作。 相似文献
993.
Although the spatial genetic differentiation that occurs in animal populations has been extensively studied, information on temporal variations in genetic structure and diversity is still lacking, especially for animals with oscillating populations. In the present study, we used the mtDNA D‐loop sequence to assess the temporal genetic variation in samples from six successive years for the greater long‐tailed hamster, Tscherskia triton. Sampling was carried out between 1998 and 2003 in cropland on the North China Plain, China. A total of 108 individuals were analyzed. The temporal samples showed a high level of genetic diversity. Substantial genetic changes in haplotype frequencies over time were detected for the hamster population. Random genetic drift and migration are likely to be the major factors responsible for the observed temporal pattern. The genetic diversity of the hamster population was higher in years with higher population density, and lower in years with lower population density. The result supports our hypothesis that genetic diversity decreases when population density declines in animals whose population oscillates greatly between years. The combined effects of inbreeding and genetic drift caused by reproduction, dispersal and population size might play important roles in the observed changes in genetic structure and diversity between years. 相似文献
994.
995.
996.
LIU Mei-lian XU Xia XIE Ping LU Jin CHEN Shu-hua ZENG Wei-min SONG Hui-ping 《园艺学报》2006,22(9):1674-1679
AIM:To investigate the influence of ovariectomy and estrogen replacement treatment on profile of gene expression in myocardium by cDNA microarray,and to characterize the targeting genes of estrogen.METHODS:cDNA microarray containing 1 400 rat cDNAs was used to study the genes differentially expressed in myocardium between sham (Ⅰ),ovariectomy (Ⅱ,OVX) and estrogen replacement treatment (Ⅲ,OVX+E2) group.Then down-regulated genes in myocardium of OVX rats were further confirmed by RT-PCR.RESULTS:177 genes were differentially expressed in myocardium between sham and OVX rats,with 91 genes up-regulated and 86 genes down-regulated in OVX rats.164 genes were differentially expressed in myocardium between OVX and OVX+E2 rats,with 113 genes up-regulated and 54 genes down-regulated in OVX rats.There were 54 genes differentially expressed in OVX compared to sham and OVX+E2.They are involved in membrane channels and transporters (18),cell receptors (9),intracellular transducers/effectors/modulator (7) and metabolism (6).Most of the genes (45) were down-regulated in OVX rats and up-regulated in OVX+E2 rats.RT-PCR test confirmed the results of cDNA microarray.CONCLUSIONS:Long-term estrogen replacement may influence the expression of genes involved in membrane channels and transporters,cell receptors,intracellular transducers/effectors/ modulator and metabolism.Long-term estrogen replacement has some beneficial effects on ionic concentration and cardiac function which partially comes from the results of influence of expression on Na+,K+-ATPase and Na+/H+ exchanger.Estrogen has an inhibitory effect on the expression of dopamine receptor,which partially clarify the myocardial protection of estrogen. 相似文献
997.
XU Xian-min WANG Ting-jie CHEN Xian-jiu ZHANG Yue-hong CHENG Niu-liang CAI Da-yong XIE Jun NIU Bo 《园艺学报》2006,22(8):1623-1627
目的:研究[Gly14]-humanin对β淀粉样蛋白1-42引起的神经干细胞毒性的作用。方法:用[Gly14]-humanin和β淀粉样蛋白1-42处理神经干细胞,观察其对神经干细胞增殖、分化的影响。结果:较低浓度的[Gly14]-humanin加入有β淀粉样蛋白1-42处理的神经干细胞培养基,经过琼脂糖凝胶电泳分析及流式细胞测定DNA含量,神经干细胞显示出对β淀粉样蛋白1-42的耐受,而对照组则显示神经干细胞出现凋亡现象。高浓度的[Gly14]-humanin加入培养基,经台盼蓝拒染法计数细胞,神经干细胞死亡率明显低于对照组,对照组神经干细胞出现大量死亡。结论:[Gly14]-humanin 不但具有抑制β淀粉样蛋白1-42对神经干细胞的毒性作用,而且在低浓度的情况下,可以促进神经干细胞的增殖和分化为神经元。 相似文献
998.
转rolA、B、C基因枳橙快繁技术 总被引:5,自引:0,他引:5
通过对转rol基因枳橙B、D、E系及对照的高接植株春梢茎段进行萌芽诱导、增殖及试管苗生根成苗的试验,摸索出适宜枳橙快繁各种培养基配方及培养条件。结果表明,以MS+6-BA1mg/L的培养基适合于芽萌发,以MS+6-BA0.5mg/L+NAA0.05mg/L的培养基适合于芽增殖,生根则以1/2MS+NAA0.5mg/L+0.2%活性炭的组合最佳,转基因各系生根率均在93.3%以上,显著高于对照生根率(66.7%)。快繁苗移栽成活率可达90%,目前生长良好。 相似文献
999.
杨梅酸性转化酶基因cDNA分离及表达分析 总被引:1,自引:0,他引:1
杨梅果实富含蔗糖,酸性转化酶是蔗糖代谢关键酶,根据植物酸性转化酶基因保守区序列设计引物,提取杨梅叶片RNA,逆转录获得cDNA,以此为模板通过PCR技术扩增到长度为516bp的基因片段,克隆入pMD18-T载体中,命名为MrIVR1(GenBank:DQ339699)。测序及同源性检索表明,该基因推导氨基酸序列与君子兰、葡萄、草莓、胡萝卜等酸性转化酶基因氨基酸序列同源性为60%~69%。运用ClustalX软件对植物转化酶基因进行了系统树分析,结果显示,MrIVR1编码的蛋白质属于细胞壁酸性转化酶。半定量RT-PCR表达分析显示,MrIVR1基因在杨梅果实发育早期表达量最高,随着果实的发育表达量下降,在成熟果实中表达水平较低。 相似文献
1000.