排序方式： 共有67条查询结果，搜索用时 330 毫秒
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采用随机克隆、功能筛选、逐次排除和同源比较的基因克隆新策略进行克隆假单胞菌(Pseudomonas sp．cn4902)磷酸甘油磷酸酯酶基因的研究。结果表明，该结构基因长819bp，与铜绿假单胞菌的磷酸甘油磷酸酯酶基因的核苷酸一致性达61．5％，氨基酸同源性为56．2％。该基因已输入GenBank数据库，收录号AF348165。将该基因转化大肠杆菌，受体菌在含NaCl 1．0mol／L的培养基中甘油含量升高2．9倍，最终菌浓度提高3．6倍。可见这是一个与生物耐盐性相关的主基因，以其转化、培育耐盐农作物的前景十分光明。 相似文献
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A cDNA microarray technique applied for analysis of global gene expression profiles in tributyltin-exposed ascidians 总被引：2，自引：0，他引：2
To analyze global gene expressions, we constructed a cDNA microarray from a basal chordate, the ascidian Ciona intestinalis. Ciona is a cosmopolitan species and a genomic analysis of Ciona revealed that ascidians had approximately 15,500 protein-coding genes. Our "Ciona intestinalis cDNA chip version 1 (Ci cDNA chip ver. 1)" has arrayed 13,400 unique Ciona cDNAs. To establish a detection system for gene expression profiles in wild ascidians using a cDNA microarray, we analyzed gene expressions in the whole body of Ciona adults after exposure to 100 nM tributyltin (TBT) for 24 h. In our preliminary array data using Ci cDNA chip ver. 1, we found more than 200 genes that showed strong differential expressions. These genes encoded proteins that were concerned with stress response, detoxification, oxidoreduction reaction, biosynthesis, and catabolism. This, the first large cDNA microarray of this animal, should facilitate analyses of global gene expressions following exposure to TBT. 相似文献
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脊尾白虾(Exopalaemon carinicauda)组织蛋白酶D基因的克隆及其表达分析 总被引：2，自引：1，他引：1
采用RACE技术获得了总长为1853bp的脊尾白虾(Exopalaemon carinicauda)组织蛋白酶D基因全长cDNA序列。该基因5′和3′非编码区分别为120bp和572bp,开放阅读框为1161bp,推测编码386个氨基酸,预测分子量为42.36kDa,理论等电点为7.54,命名为EcCatD基因。同源性和系统进化分析表明,EcCatD基因与斑节对虾、美洲螯龙虾的相似性分别为86%和80%,与斑节对虾和美洲螯龙虾紧密聚为一支。荧光定量RT-PCR结果表明,EcCatD基因在血细胞中的相对表达量最高,其次为肝胰腺。该基因在鳗弧菌和WSSV感染后的脊尾白虾血细胞和肝胰腺中的表达量显著增加,并具有不同的时空表达趋势。结果表明EcCatD基因在脊尾白虾免疫反应中具有重要作用。 相似文献
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根据NCBI数据库中已发表的溶藻弧菌(Vibrio alginolyticus)全基因组序列合成一对特异性引物,应用聚合酶链式反应(PCR技术)扩增溶藻弧菌HY9001菌株dtd基因,将其定向克隆到原核表达载体pET-32a构建重组表达质粒pET-DTD,并对其进行诱导温度、诱导时间、诱导IPTG浓度等条件的优化,最后探究其纯化时最佳咪唑洗脱浓度。结果表明:DTD蛋白成功表达,且其以包涵体的形式存在,在诱导温度37℃、IPTG浓度0.1 mmol/L条件下诱导5 h表达量最高,纯化最佳咪唑洗脱浓度为150 mmol/L。 相似文献
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New empirical models were developed to predict the soil deformation moduli using gene expression programming (GEP). The principal soil deformation parameters formulated were secant (Es) and reloading (Er) moduli. The proposed models relate Es and Er obtained from plate load-settlement curves to the basic soil physical properties. The best GEP models were selected after developing and controlling several models with different combinations of the influencing parameters. The experimental database used for developing the models was established upon a series of plate load tests conducted on different soil types at depths of 1–24 m. To verify the applicability of the derived models, they were employed to estimate the soil moduli of a part of test results that were not included in the analysis. The external validation of the models was further verified using several statistical criteria recommended by researchers. A sensitivity analysis was carried out to determine the contributions of the parameters affecting Es and Er. The proposed models give precise estimates of the soil deformation moduli. The Es prediction model provides considerably better results in comparison with the model developed for Er. The simplified formulation for Es significantly outperforms the empirical equations found in the literature. The derived models can reliably be employed for pre-design purposes. 相似文献
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目的 探讨研究同型半胱氨酸（homocysteine,Hcy）水平与脑梗死患者亚甲基四氢叶酸还原酶（MTHFR）基因C677T的多态性之间的相关性。方法 选择2012年2月~2015年8月期间在笔者医院住院就诊的450例脑梗死患者作为研究组,其中糖尿病患者181例,非糖尿病患者269例,另外选择285例笔者医院门诊部健康的体检人员作为对照组,分别采用焦磷酸测序的方法检测分析MTHFR基因C677T的多态性,并分析各基因型与Hcy水平之间的相关性。结果 脑梗死组与健康对照组的MTHFR基因型分布之间的差异具有统计学意义（P<0.05）,脑梗死组T基因的频率明显比对照组高,差异有统计学意义（χ2=13.67,P=0.00）。脑梗死组患者的Hcy浓度明显高于健康对照组,差异有统计学意义（t=12.71,P=0.00）。脑梗死组患者各MTHFR基因型患者的Hcy水平之间比较,差异有统计学意义（F=17.68,P=0.00）。非糖尿病脑梗死患者的Hcy水平明显高于糖尿病脑梗死患者,差异有统计学意义（t=2.97,P=0.00）,非糖尿病组TT型的Hcy浓度明显高于糖尿病组,CC型的Hcy浓度明显低于糖尿病组,差异均有统计学意义（t=5.67,2.18;P=0.00,0.03）。糖尿病性脑梗死患者和非糖尿病脑梗死患者中,MTHFR基因为TT型的Hcy水平明显高于CC型和CT型,差异均有统计学意义（P<0.05）,而CC型和CT型的Hcy水平之间比较差异无统计学意义（P>0.05）。结论 脑梗死患者比健康人的MTHFR基因C677T的T等位基因频率高,且脑梗死患者的MTHFR基因C677T为TT基因型时血清中Hcy的水平更高,由此判断TT基因型可能是脑梗死发生的危险因素。 相似文献
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我国引种海带(Laminaria japonica)和长海带(L.longissima)配子体克隆的随机扩增多态性DNA分析 总被引：1，自引：0，他引：1
运用RAPD技术,对引种我国的海带(Laminaria japonica)和长海带(L.longissima)的22个配子体克隆进行分析。筛选的19条随机引物共获得252个位点.扩增片段大小在200～2000bp之间,多态性位点228个,占90.5%。配子体克隆遗传变异分析表明,长海带和海带的遗传多样性都比较高,两者之间的遗传分化较为明显,且种间变异大于种内变异。长海带和海带雄配子体克隆的遗传变异程度均低于雌配子体克隆。另外,两个种的雌、雄配子体之间均存在一定程度的分化,且长海带雌、雄配子体之间的遗传分化大于海带配子体。 相似文献
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