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991.
To investigate the population densities of potential malaria vectors, Anopheles species were collected by light traps in malaria endemic areas, Paju and Gimpo, Gyeonggi-do of Korea. Five Anopheles Hyrcanus sibling species (An. sinensis, An. pullus, An. lesteri, An. kleini, and An. belenrae) were identified by PCR. The predominant species, An. pullus was collected during the late spring and mid-summer, while higher population consists of An. sinensis were collected from late summer to early autumn. These 2 species accounted for 92.1% of all Anopheles mosquitoes collected, while the other 3 species accounted for 7.9%. Taking into account of these population densities, late seasonal prevalence, and long-term incubation period (9-13 months) of the Korean Plasmodium vivax strain, An. sinensis s.s is thought to play an important role in the transmission of vivax malaria in the study areas. 相似文献
992.
Jun Zou Jiali Zhu Shunmou Huang Entang Tian Yong Xiao Donghui Fu Jinxing Tu Tingdong Fu Jinling Meng 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,120(2):283-290
Accumulated evidence has shown that each of the three basic Brassica genomes (A, B and C) has undergone profound changes in different species, and has led to the concept of the “subgenome”.
Significant intersubgenomic heterosis was observed in hybrids between traditional Brassica napus and first generation lines of new type B. napus. The latter were produced by the partial introgression of subgenomic components from different species into B. napus. To increase the proportion of exotic subgenomic components and thus achieve stronger heterosis, lines of first generation
new type B. napus were intercrossed with each other, and subjected to intensive marker-assisted selection to develop the second generation
of new type B. napus. The second generation showed better agronomic traits and a higher proportion of introgression of subgenomic components than
did the first generation. Compared with the commercial hybrid and the hybrids produced with the first generation new type
B. napus, the novel hybrids showed stronger heterosis for seed yield during the 2 years of field trials. The extent of heterosis showed
a significant positive correlation with the introgressed subgenomic components in the parental new type B. napus. To increase the content of the exotic subgenomic components further and to allow sustainable breeding of novel lines of
new type B. napus, we initiated the development of a gene pool for new type B. napus that contained a substantial amount of genetic variation in the Ar and Cc genome. We discuss new approaches to broaden the avenue of intersubgenomic heterosis in oilseed Brassica. 相似文献
993.
Liguang Sun Jianfei Guo Robert Brown Takashi Amagai Yong Zhao Dong‐Ming Su 《Aging cell》2010,9(3):347-357
Age‐related thymic involution may be triggered by gene expression changes in lymphohematopoietic and/or nonhematopoietic thymic epithelial cells (TECs). The role of epithelial cell‐autonomous gene FoxN1 may be involved in the process, but it is still a puzzle because of the shortage of evidence from gradual loss‐of‐function and exogenous gain‐of‐function studies. Using our recently generated loxP‐floxed‐FoxN1(fx) mouse carrying the ubiquitous CreERT (uCreERT) transgene with a low dose of spontaneous activation, which causes gradual FoxN1 deletion with age, we found that the uCreERT‐fx/fx mice showed an accelerated age‐related thymic involution owing to progressive loss of FoxN1+ TECs. The thymic aging phenotypes were clearly observable as early as at 3–6 months of age, resembling the naturally aged (18–22‐month‐old) murine thymus. By intrathymically supplying aged wild‐type mice with exogenous FoxN1‐cDNA, thymic involution and defective peripheral CD4+ T‐cell function could be partially rescued. The results support the notion that decline of a single epithelial cell‐autonomous gene FoxN1 levels with age causes primary deterioration in TECs followed by impairment of the total postnatal thymic microenvironment, and potentially triggers age‐related thymic involution in mice. 相似文献
994.
Xinxian Qiao Liyong Zhang Armin M Gamper Takeo Fujita Yong Wan 《Cell cycle (Georgetown, Tex.)》2010,9(19):3904-3912
Anaphase-promoting complex/cyclosome (APC/C) is a multifunctional ubiquitin-protein ligase that targets various substrates for proteolysis inside and outside of the cell cycle. The activation of APC/C is dependent on two WD-40 domain proteins, Cdc20 and Cdh1. While APC/Cdc20 principally regulates mitotic progression, APC/Cdh1 shows a broad spectrum of substrates in and beyond cell cycle. In the past several years, numerous biochemical and mouse genetic studies have greatly attracted our attention to the emerging role of APC/Cdh1 in genomic integrity, cellular differentiation and human diseases. This review will aim to summarize the recently expanded understanding of APC/Cdh1 in regulating biological function and how its dysfunction may lead to diseases.Key words: APC/C, Cdh1, proteolysis, genomic integrity, signal transduction, differentiation, tumorigenesis 相似文献
995.
996.
通过构建pVB4215植物双元表达载体,采用农杆菌介导法转化烟草,研究VviDREB1在植物体中的异源表达特性.结果显示,实验获得了25个Hyg抗性株系,经过PCR、RT-PCR和GUS组织化学染色检测及Hyg基因的PCR复检等多点验证,证实表达载体边界内序列完整地整合到2个烟草株系的基因组中.转基因烟草株系在4℃低温处理20 h后,恢复生长5 h,叶片光系统PSⅡ抗寒性分析结果表明,转基因植株的叶片快速叶绿素荧光曲线OJIP各点数值高于对照植株,VviDREB1基因能够显著提高烟草的荧光产量,最大光化学效率Fv/Fm和以吸收光能为基础的性能指数PIABS较对照高,说明VviDREB1对保护植物组织细胞内光合系统PSⅡ有明显的作用,转VviDREB1基因烟草对低温有一定的忍耐能力. 相似文献
997.
猕猴桃花粉原位生长过程中Ca2+的超微细胞化学定位 总被引:2,自引:0,他引:2
应用扫描电镜和荧光显微镜对软枣猕猴桃同种花粉在柱头上原位萌发及花粉管生长情况进行了观察,并用焦锑酸盐沉淀法对其授粉前后柱头及花柱中Ca2+进行超微细胞化学定位.结果显示:(1)猕猴桃柱头属于干性柱头,具有一道裂沟,乳突呈长圆柱形,授粉前后形态差异不明显.(2)授粉后3 h,花粉管生长穿过柱头表面,授粉后7 h,花粉管生长到达花柱底部;(3)授粉前后,柱头接受面靠近柱头外围细胞的角质层一侧细胞器内含有丰富的钙,而柱头非接受表面钙颗粒分布很少;(4)授粉前和授粉后3 h,花柱顶端钙颗粒较少,基部钙颗粒较多;授粉后7 h,花柱顶端和基部钙分布密度无明显差别;(5)授粉前后花柱顶端钙主要均匀分布在细胞质膜位置;在花柱基部授粉前钙主要分布在引导组织胞间隙中,授粉后3 h主要分布在细胞质内,授粉后7 h主要存在于细胞质、内质网上.研究表明,猕猴桃授粉前后,柱头和花柱组织中均含有钙,授粉前和授粉后3 h花柱中的钙呈现出梯度分布,授粉后7 h钙的梯度分布现象减弱甚至消失. 相似文献
998.
野生甜瓜'云甜-930'对白粉病抗性的遗传分析 总被引:2,自引:0,他引:2
以经过多代自交选育的高抗白粉病材料野生甜瓜'云甜-930'(P1)与感病栽培甜瓜'华莱士'(P2)组配,构建了P1、P2、F1、B1、B2和F2 6个世代,对大棚栽培条件下各世代材料的白粉病自然发病状况进行考察,用植物数量性状主基因+多基因混合遗传模型的多世代联合分析法,研究野生甜瓜'云甜-930'对白粉病的抗性遗传规律.结果显示:野生甜瓜'云甜-930'对白粉病的抗性遗传符合2对加性-显性-上位性主基因+加性-显性-上位性多基因混合遗传模型(E-0),2对主基因的加性效应相等,da和db均为-15.76,2对主基因的显性效应ha和hb分别为14.98和19.87,第2对主基因的显性效应大于第1对;2对主基因互作效应中除了显性×显性效应(l=-7.73)较小外,其它互作效应均较大,加性×加性效应i为31.46,加性×显性效应jab为-26.86,而显性×加性效应jba为-17.07.该组合的B1、B2和F2群体抗病性主基因遗传率分别为73.31%、69.15%和97.61%,多基因遗传率分别为18.83%、25.86%和0,环境变异在2.39%~7.86%之间.研究表明,野生甜瓜'云甜-930'对白粉病的抗性受2对加性-显性-上位性主基因+加性-显性-上位性多基因控制,同时还受到环境的影响.在甜瓜抗白粉病育种中,在F2代主基因的选择效率最高. 相似文献
999.
三亚市果蔬地重金属空间分布及其污染评价 总被引:2,自引:0,他引:2
通过野外调查采样,采用标准对比法和地累积指数法,评价了三亚市果蔬地表层土壤重金属的污染状况。结果表明:土壤中Hg、Cd、Cr、Pb和As5种重金属的积累不显著,其平均值均未超过国家环境质量二级标准(GB15618-1995);但Hg、Cd和Pb的平均值高于海南岛农用地的自然背景值,表明存在区域轻度污染;Cr、Hg、Pb和As4种重金属元素的变异系数均>1,表明土壤中Cr、Hg、Pb和As的分布极不均匀。同时,利用地理信息系统(GIS)Krging插值方法得到了5种重金属的空间分布图,显示出不同重金属元素的空间分异特征,为三亚市果蔬地的可持续开发利用提供指导。 相似文献
1000.