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运用差异显示PCR(DD-PCR)方法分析棉铃虫滞育解除蛹差异表达的基因,结果得到了56个差异片段.通过RT-PCR和Real-time PCR的方法,鉴定了滞育解除过程中有3个基因表达量在下调,有4个基因表达量在上调.这7个差异表达基因中有3个和已知的基因有较高的同源性:FKBP12,esr16和NADH dehydrogenase 1 alpha subcomplex subunit 6.这些差异基因为今后研究滞育解除的分子机制提供了新的线索.  相似文献   

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通过对开洞砖砌体进行的拟静力试验,以泥浆砌筑的北京地区典型农宅的前纵墙作为研究对象,设计了3片采用不同加固措施的开洞墙体.从破坏情况、极限荷载与开裂位移等方面对3片墙体进行了对比分析,得出开洞墙体抗震的薄弱环节.并对钢丝网水泥砂浆加固和钢窗框加固两种方法的加固和增加效果及破坏特征进行了分析,提出了两种加固方式的加固建议.  相似文献   

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To identify the genes associated with cellular rejection in pig-to-human xenotransplantation, the suppression subtractive hybridization (SSH) was used in screening the up-regulated genes from a co-culture of human peripheral blood mononuclear cells (PBMCs) and porcine vascular endothelial cell line PIEC. The up-regulated cDNAs were cloned into pGEM-T Easy vector and then sequenced. Nucleic acid homology searches were performed using the BLAST program. A subtracted cDNA library including about 300 clones with the expected up-regulated genes was obtained. Twenty-four of these clones were analyzed by sequencing and homology comparison was made. These clones represent the genes of human perforin (PRF1), proteasome, lymphocyte specific interferon regulatory factor/interferon regulatory factor 4 (LSIRF/IRF 4), muscleblind-like (MBNL) protein and a porcine expressed sequence tag (EST) which has 81% homology with human oxidative-stress responsive 1 (OSR 1). These genes might be the candidate genes which are associated with cellular rejection in pig-to-human xenotransplantation.  相似文献   

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目的:筛选与乳腺癌发病相关的关键基因,为研究乳腺癌的诊疗提供新的潜在分子靶标.方法:使用GEO2R在线工具比较乳腺癌与正常乳腺组织基因表达情况,进行差异显著性分析,利用基因功能注释工具DA-VID对差异基因进行GO和KEGG富集分析.通过STRING数据库构建差异基因的蛋白互作网络,基于最大团中心性(maximal c...  相似文献   

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对比研究了普通低碳钢筋(LC)和2种耐蚀钢筋(1%Cr和6%Cr)在未碳化(p H=12.6)与碳化(p H=10.6)模拟混凝土孔溶液中加入氯离子后的腐蚀行为.采用线性极化电阻(LPR)和电化学阻抗谱(EIS)表征钢筋的电化学行为,并通过扫描电子显微镜(SEM)和X射线能谱仪(EDS)对腐蚀产物进行微观形貌观察和元素分析.结果表明:在点蚀阶段,与LC钢筋相比,1%Cr钢筋的临界氯离子值未提高,而6%Cr钢筋则提高5~10倍;在腐蚀扩展阶段,1%Cr的耐蚀性能与LC钢筋相比有小幅提升,可能的原因是1%Cr钢筋中的Cr促使生成致密锈层.  相似文献   

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Leaf senescence in plants is an essential develop- mental phase, and an understanding of senescence is important not only for pure scientific reasons, but also for practical purposes. During the last decade, a number of senescence-associated genes (SAGs) …  相似文献   

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M P Lefranc  A Forster  T H Rabbitts 《Nature》1986,319(6052):420-422
Selective cloning procedures for T-cell-specific complementary DNAs have revealed the existence of a gene designated gamma as well as the main antigen receptor alpha- and beta-chain genes. The gamma-chain genes undergo rearrangement during T-cell differentiation but the patterns and complexity of such rearrangements differ markedly in mouse and human. In mouse, a panel of cytotoxic T-lymphocyte clones exhibit the same rearrangement pattern with a gamma-chain gene probe and a set of three gamma-chain variable (V) genes have been identified in the DNA. Clonal diversity in mouse seems to be confined to V-J (joining) regions. In contrast, human T-cell lines exhibit diverse rearrangements suggestive of a family of differing V gamma genes variously rearranging to the two gamma-chain constant (C) region genes. Here we report the cloning of two very different V gamma genes rearranged to J segments upstream of the two human C gamma genes. Both V gamma genes are rearranged productively but nucleotide sequence comparison shows that they possess very little homology with each other. This shows that human T-cell V gamma genes exist which differ significantly from each other at the nucleotide level and that such diverse genes can be usefully rearranged in different T cells.  相似文献   

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海边月见草茎提取物经X-5大孔树脂吸附,用体积分数为10%、30%、50%、70%的乙醇溶液进行洗脱,得到4种洗脱级分.采用二苯代苦肼自由基(DPPH·)体系、羟自由基体系、超氧阴离子自由基体系及抗卵黄脂蛋白脂质过氧化体系对4个级分的抗氧化活性进行了测定.结果表明,海边月见草茎提取物4种洗脱级分具有不同程度的清除自由基能力,其中30%乙醇级分的抗氧化活性最强.该级分对DPPH自由基的清除率为82.60%,对H2O2/Fe2 产生羟自由基的清除率为65.43%,对邻苯三酚自氧化产生超氧阴离子自由基的抑制率为26.16%,对卵黄脂蛋白PUFA过氧化的抑制率为80.97%.综合评价其抗氧化活性比芦丁好或相当,但比槲皮素略差.同时显示抗氧化活性与其黄酮体积分数有一定的相关性.  相似文献   

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The composition of ices in comets may reflect that of the molecular cloud in which the Sun formed, or it may show evidence of chemical processing in the pre-planetary accretion disk around the proto-Sun. As carbon monoxide (CO) is ubiquitous in molecular clouds, its abundance with respect to water could help to determine the degree to which pre-cometary material was processed, although variations in CO abundance may also be influenced by the distance from the Sun at which comets formed. Observations have not hitherto provided an unambiguous measure of CO in the cometary ice (native CO). Evidence for an extended source of CO associated with comet Halley was provided by the Giotto spacecraft, but alternative interpretations exist. Here we report observations of comet Hale-Bopp which show that about half of the CO in the comet comes directly from ice stored in the nucleus. The abundance of this CO with respect to water (12 per cent) is smaller than in quiescent regions of molecular clouds, but is consistent with that measured in proto-stellar envelopes, suggesting that the ices underwent some processing before their inclusion into Hale-Bopp. The remaining CO arises in the coma, probably through thermal destruction of more complex molecules.  相似文献   

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In this study, we selected 10 susceptible SNPs loci to investigate their contribution to susceptibility to type 2 diabetes in Han Chinese among Hubei population. We genotyped SNPs rs5219, rs1801282, rs1470579, rs1111875, rs1081661, rs7754840, rs4506565, rs13266634, rs4402960, and rs5643981 by using the method of polymerase chain reaction-ligase detection reaction (PCR-LDR). In a case-control study, we have genotyped the 10 candidate susceptibility SNP loci, and here, we reported that the SNP rs5219 in KCNJ1...  相似文献   

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通过对两种不同配钢形式的6个钢骨混凝土异形柱双向偏心受压破坏试验,研究分析了这两种配钢形式异形柱的工作机理、破坏形态和极限承载力.  相似文献   

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