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排序方式: 共有2945条查询结果,搜索用时 93 毫秒
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Fei Mi Ying Zhang Dan Yang Xiaozhao Tang Pengfei Wang Xiaoxia He Yunrun Zhang Jianyong Dong Yang Cao Chunli Liu Ke-Qin Zhang Jianping Xu 《PloS one》2016,11(2)
During the past 40 years, more than 400 Sudden Unexplained Deaths (SUDs) have occurred in Yunnan, southwestern China. Epidemiological and toxicological analyses suggested that a newly discovered mushroom called Trogia venenata was the leading culprit for SUDs. At present, relatively little is known about the genetics and natural history of this mushroom. In this study, we analyzed the sequence variation at four DNA fragments among 232 fruiting bodies of T. venenata collected from seven locations. Our ITS sequence analyses confirmed that all the isolates belonged to the same species. The widespread presence of sequence heterozygosity within many strains at each of three protein-coding genes suggested that the fruiting bodies were diploid, dikaryotic or heterokaryotic. Within individual geographic populations, we found significant deviations of genotype frequencies from Hardy-Weinberg expectations, with the overall observed heterozygosity lower than that expected under random mating, consistent with prevalent inbreeding within local populations. The geographic populations were overall genetically differentiated. Interestingly, while a positive correlation was found between population genetic distance and geographic distance, there was little correlation between genetic distance and barium concentration difference for the geographic populations. Our results suggest frequent inbreeding, geographic structuring, and limited gene flow among geographic populations of T. venenata from southwestern China. 相似文献
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P J McAlpine N Van Cong C Boucheix A J Pakstis R C Doute T B Shows 《Cytogenetics and cell genetics》1987,46(1-4):29-101
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Nguyen van Cong G. Uzan M. S. Gross C. Jegou-Foubert P. Frachet C. Boucheix G. Marguerie J. Frézal 《Human genetics》1988,80(4):389-392
Summary The platelet GPIIb-IIIa complex functions as a receptor for fibrinogen, fibronectin, and von Willebrand factor on activated platelets. This glycoprotein is a member of a broadly distributed family of structurally and immunologically related membrane receptors involved in cell-cell contact and cell-matrices interactions. GPIIb-IIIa is a heterodimer complex composed of GPIIb (the subunit), which consists of two disulfide-linked heavy and light chains, and GPIIIa (the subunit), which is a single polypeptide chain. Congenital absence of platelet GPIIb-IIIa in Glanzmann's thrombasthenia results in a severe bleeding disorder characterized by defective platelet aggregation and failure of fibrinogen to bind to platelets. The gene coding for GPIIb was located on 17q21.1-17q21.3 as determined by in situ hybridization with a 2650-pb GP2B (GPIIb) cDNA probe prepared from human megakaryocytes. 相似文献
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ESR检测大鼠肺巨噬细胞释放的活性氧自由基 总被引:4,自引:0,他引:4
用ESR捕捉技术检测大鼠AM释放的活性氧自由基的性质表明:1.PMA和BCG均能刺激AM产生较强的OH·;能刺激人末稍血白细胞释放活性氧自由基的ConA和顺铂在本实验条件下未能使AM产生活性氧自由基信号。2.经膜活性剂PMA刺激的AM所释放活性氧自由基的高峰在刺激后2min,而经颗粒性物质BCG刺激,AM释放自由基的高峰时间明显后移。3.测试体系中的AM数过多或过少都不适合捕捉ESR信号。在本实验条件下,捕捉到最高自由基信号的AM终浓度为5×107AM/ml。4.测试体系中存在DETAPAC或EDTA,可使捕捉到的自由基信号明显增强。 相似文献
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酪氨酸羟化酶基因载体-pCMVTH 质粒的构建及在大鼠骨骼肌内的表达 总被引:4,自引:0,他引:4
为用转基因方法治疗巴金森氏病大鼠模型,本研究采用分子克隆技术,将合成多巴胺的关键酶-酪氨酸羟化酶(TH)的基因,克隆进入以巨细胞病毒CMV为启动子的载体质粒内,经限制性内切酶定位分析证实该重组的DNA质粒的可靠性。携带TH基因的PCMVTH质粒以LIPO-FECTIN介导,在培养的原代骨骼肌细胞中高效表达。本研究为进一步用转基因的细胞植入脑内以治疗巴金森氏病打下一定基础。 相似文献
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Artificial mosaic protein containing antigenic epitopes of hepatitis E virus. 总被引:2,自引:0,他引:2
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Y E Khudyakov M O Favorov N S Khudyakova M E Cong B P Holloway N Padhye S B Lambert D L Jue H A Fields 《Journal of virology》1994,68(11):7067-7074
A synthetic gene encoding an artificial polypeptide composed of antigenic epitopes of the hepatitis E virus (HEV) proteins was constructed from short oligodeoxyribonucleotides by using PCR. The polypeptide comprises a mosaic of three antigenically active dominant regions from the protein encoded by open reading frame 2 (ORF2), one antigenically active region from the protein encoded by ORF3 of the Burmese HEV strain, and one antigenically active region from the protein encoded by ORF3 of the Mexican HEV strain. The mosaic protein was expressed in Escherichia coli as a chimera with glutathione S-transferase or beta-galactosidase. Guinea pig sera containing antibodies to the corresponding HEV synthetic peptides were used to demonstrate by Western immunoblot analysis and enzyme immunoassay the presence and accessibility of all HEV-specific antigenic epitopes introduced into the mosaic protein. Both the glutathione S-transferase and beta-galactosidase hybrid proteins were analyzed by using a panel of human anti-HEV-positive and -negative sera. The data obtained strongly indicate a diagnostic potential for the mosaic protein. 相似文献
10.
水分胁迫对小麦光系统Ⅱ的影响 总被引:10,自引:0,他引:10
水分胁迫可降低小麦叶绿体的室温荧光产量和Mg2+ 在两个光系统间的调节能力、叶片的可变荧光产量、可变荧光猝灭速率以及荧光上升互补面积,表明光系统Ⅱ受到了伤害。光系统Ⅱ氧化侧的人工电子供体DPC能部分恢复受到抑制的叶绿体可变荧光,说明水分胁迫对光系统Ⅱ的损伤部位不仅位于氧化侧,也可能在反应中心上 相似文献