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151.
用抑制性差减杂交构建新疆Kaposi肉瘤差异表达基因文库 总被引:11,自引:0,他引:11
目的:分离卡波氏肉瘤(Kaposi′s sarcoma,KS)差异表达基因,并建立相应的cDNA文库,为从分子水平揭示KS发病机制打下良好的基础。方法:采集KS肉瘤及来源于同一患者的正常皮肤组织,抽提总RNA,经逆转录酶合成dscDNA,并经RsaⅠ酶切,与2种不同的接头衔接,分别以正常组织和肿瘤组织作为tester和driver,进行双向抑制性差减杂交(suppression subtractive hybridization,SSH),初步筛选KS肉瘤与正常皮肤差异表达基因,将差异基因PCR扩增,产物与pGEM-Teasy克隆载体连接,转化DH5α大肠杆菌,采用蓝白斑筛选,获得白色阳性克隆菌落,并煮沸破菌,PCR扩增出未知基因片段。结果:差减得到差异基因片段多位于200~500bp,成功构建了2个分别代表在KS肿瘤组织中表达上调和下调的基因文库。结论:经双向抑制性差减杂交获得了KS差异表达基因文库。抑制性差减杂交是一种快速、方便、有效的建立差异基因文库的方法。 相似文献
152.
Qiuyue Ma Kai Feng Wanxu Yang Yingnan Chen Faxin Yu Tongming Yin 《Molecular biology reports》2014,41(5):3219-3223
In this study, single-nucleotide polymorphisms (SNPs) and insertions/deletions (InDels) in the genome of Ziziphus jujuba were identified using sequences generated by the Roche 454 GS-FLX sequencer. A total of, 573,141 reads were produced with an average read length of 360 bp. After quality control, 258,754 of the filtered reads were assembled into 23,864 contigs, and 293,458 remained as singletons. Using the contig assemblies as a reference, 17,160 SNPs and 478 InDels were identified. Among the SNPs, transitions occurred three times more frequently than transversions. In transitions, the number of C/T and G/A transitions was similar. Among the transversions, A/T was the most abundant, and C/G was much rarer than any of the other types of transversions, accounting for only about half the numbers of A/C, A/T and G/T transversions. For the InDels, mononucleotide changes amounted to 64.4 % of the total number of InDels. In general, the frequency of detected InDels decreased as the length of the InDels increased. This study provides valuable marker resources for future genetic studies of Ziziphus spp. 相似文献
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154.
Background
All modern rosids originated from a common hexapolyploid ancestor, and the genomes of some rosids have undergone one or more cycles of paleopolyploidy. After the duplication of the ancient genome, wholesale gene loss and gene subfunctionalization has occurred. Using the extensin super-gene family as an example, we tracked the differential retention and expansion of ancestral extensin genes in four modern rosids, Arabidopsis, Populus, Vitis and Carica, using several analytical methods.Results
The majority of extensin genes in each of the modern rosids were found to originate from different ancestral genes. In Arabidopsis and Populus, almost half of the extensins were paralogous duplicates within the genome of each species. By contrast, no paralogous extensins were detected in Vitis and Carica, which have only undergone the common γ-triplication event. It was noteworthy that a group of extensins containing the IPR006706 domain had actively duplicated in Arabidopsis, giving rise to a neo-extensin around every 3 million years. However, such extensins were absent from, or rare in, the other three rosids. A detailed examination revealed that this group of extensins had proliferated significantly in the genomes of a number of species in the Brassicaceae. We propose that this group of extensins might play important roles in the biology and in the evolution of the Brassicaceae. Our analyses also revealed that nearly all of the paralogous and orthologous extensin-pairs have been under strong purifying selection, leading to the strong conservation of the function of extensins duplicated from the same ancestral gene.Conclusions
Our analyses show that extensins originating from a common ancestor have been differentially retained and expanded among four modern rosids. Our findings suggest that, if Arabidopsis is used as the model plant, we can only learn a limited amount about the functions of a particular gene family. These results also provide an example of how it is essential to learn the origination of a gene when analyzing its function across different plant species.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-612) contains supplementary material, which is available to authorized users. 相似文献155.
目的:探讨孟鲁斯特钠对儿童阻塞性睡眠呼吸暂停低通气综合征(obstructive sleep apnea hypopnea syndrome,OSAHS)治疗疗效。方法:对经电子鼻咽喉镜检查腺样体III、IV级经多导睡眠监测为OSAHS的儿童96例,分成两组:药物治疗组48例,使用孟鲁斯特钠,连续使用1个月以上;未用药物组48例。对其家长进行相关临床表现的问卷调查。结果:两组患儿在年龄、病程、伴有鼻部疾病情况以及临床问卷分值间均无显著性差异(P0.05)。3个月后随访情况为,药物治疗组经治疗后在"响鼾"、"不安宁的睡眠或频繁醒觉"、"鼻阻塞而张口呼吸"以及"鼻腔很多鼻涕"4个症状的改善有统计学差异(P0.05)。未用药物组随访前、后问卷调查,差异均不具有显著性(P0.05)。结论:孟鲁斯特钠对儿童OSAHS治疗有一定疗效,可先行药物治疗。症状仍无明显改善的再考虑选择手术治疗。 相似文献
156.
[目的] 明确世界自然保护联盟公布的“世界100种恶性外来入侵物种”在我国大陆发生分布现状,为我国制定外来入侵物种管控对象和分级管理对策提供依据。[方法] 基于在线数据库系统、文献报道以及外来入侵物种本底调查结果,采用分类统计方法,对物种的分类地位、原产地、在我国的入侵状态及其所在的生态系统进行分析。[结果] 世界100种恶性外来入侵物种已有82种在我国发生分布,包括本地种33种、外来入侵种32种、外来非入侵种16种,以及未明确入侵状态1种。其中,32种外来入侵种包括陆生无脊椎动物8种、哺乳动物2种、鱼类2种、两栖动物1种、爬行动物1种、水生无脊椎动物2种、陆生植物9种、水生植物4种、真菌1种、卵菌1种和病毒1种。以上物种主要分布在东南沿海地区和西南地区,而较少分布在西北地区和东北地区;约75%物种分布在农田、城镇、森林和湿地4类生态系统。[结论] 建议外来入侵物种管理部门重点关注尚未在国内发生分布的18种潜在外来入侵物种,并列入国家外来入侵物种相关管理对象,严防其传入与扩散;严密监控国内已发生且具有潜在危险的外来物种,防止其向可能入侵的生态系统边缘扩散;继续对在国内已发生的外来入侵种实施区域性分级控制管理措施。 相似文献
157.
以广州地区常见的200种(含变种、变型和品种)可食用植物为材料,对植物不同部位呈现的颜色以及不同季节色彩分布情况进行统计分析,总结可食用植物在色彩方面的特点及局限。其中,可食用植物叶、茎色以绿色为主,花、果色丰富。以色彩理论为基础,对可食用植物进行种植搭配实验,归纳相应的植物色彩搭配策略。策略包括三个方面,针对可食用植物叶色特点,提出绿色调可食用植物搭配策略;针对可食用植物色彩丰富度的差异,提出多部位色彩组合策略;针对植物时间维度的色彩分布差异及衔接空缺,提出持续的色彩植物搭配建议。 相似文献
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Yingnan Huang Hao Wu Ruyi Xue Taotao Liu Ling Dong Jun Yao Yang Zhang Xizhong Shen 《PloS one》2013,8(10)