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K202A突变对扩展青霉脂肪酶热稳定性的影响 被引量:7
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作者 邹有土 吴义真 +1 位作者 施文芳 林琳 《中国生物工程杂志》 CAS CSCD 北大核心 2007年第12期52-56,共5页
利用易错PCR定向进化扩展青霉脂肪酶(PEL),获得了一株热稳定性有所提高的随机突变体(ep8),ep8包含有一个氨基酸的改变。为进一步提高其热稳定性,利用重叠延伸PCR法,以ep8基因为模板,将第202位赖氨酸突变为丙氨酸(K202A),构建表达质粒pAO... 利用易错PCR定向进化扩展青霉脂肪酶(PEL),获得了一株热稳定性有所提高的随机突变体(ep8),ep8包含有一个氨基酸的改变。为进一步提高其热稳定性,利用重叠延伸PCR法,以ep8基因为模板,将第202位赖氨酸突变为丙氨酸(K202A),构建表达质粒pAO815-ep8-K202A。并将其引入毕赤酵母GS115构建叠加突变体(PEL-ep8-K202A)。同时以野生型lip07为模板构建单点突变体:PEL-lip07-K202A。15%SDS-PAGE结果分析表明突变体分子量与野生型一致,约为28kDa。表达产物热稳定性分析结果表明:野生型(PEL)的Tm值为39.03℃,而以野生型为模板进行定点突变得到的单点突变酶(PEL-lip07-K202A),其Tm却降低了2℃,为37.08℃。叠加突变酶(PEL-ep8-K202A)的Tm为41.66℃,比野生型酶提高2.63℃,比随机突变体ep8生产的酶(PEL-ep8)的Tm提高了1.21℃。 展开更多
关键词 扩展青霉脂肪酶 定点突变稳定性
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拟南芥热敏感突变体的研究进展
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作者 张燕 刘箭 冯玉芹 《山东师范大学学报(自然科学版)》 CAS 2010年第1期136-140,共5页
在自然界中,植物经常会遭受多种恶劣环境的胁迫,高温胁迫就是其中之一.由于温室效应导致全球气温不断升高,高温胁迫频发且强度也愈来愈大,因此,有关植物耐热分子机理和耐热相关基因研究的重要性也更加凸显.本文作者综合介绍了多... 在自然界中,植物经常会遭受多种恶劣环境的胁迫,高温胁迫就是其中之一.由于温室效应导致全球气温不断升高,高温胁迫频发且强度也愈来愈大,因此,有关植物耐热分子机理和耐热相关基因研究的重要性也更加凸显.本文作者综合介绍了多种拟南芥热敏感突变体的最新研究成果,及其耐热相关基因的生物学功能,以期为今后研究植物耐热提供借鉴. 展开更多
关键词 拟南芥 敏感突变
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人热休克因子1突变体的应用研究进展
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作者 黄运洪 龚守芳 邹江英 《生物工程学报》 CAS CSCD 北大核心 2007年第6期971-975,共5页
热休克因子1是调节应激反应的主要转录因子,它在应激条件下可被活化。通过基因突变得到正显性和负显性热休克因子1,它们不需要外界条件刺激就分别具有启动热休克蛋白的表达或竞争抑制内源热休克因子1活性的能力。目前,已有多个热休克因... 热休克因子1是调节应激反应的主要转录因子,它在应激条件下可被活化。通过基因突变得到正显性和负显性热休克因子1,它们不需要外界条件刺激就分别具有启动热休克蛋白的表达或竞争抑制内源热休克因子1活性的能力。目前,已有多个热休克因子1的突变体应用于疾病研究。介绍了热休克因子1的结构和活化途径,以及热休克因子1突变体在肿瘤、神经系统及心血管系统等方面的应用进展。 展开更多
关键词 休克因子 休克因子1突变 休克蛋白 应激反应
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人热激因子-1突变体hHSF190/2在大肠杆菌和毕赤酵母中的表达及其活性研究
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作者 林锦梅 龚守芳 +6 位作者 鄂顺梅 黄运洪 赖坤 朱海燕 赵远波 侯永辉 邹江英 《生物技术通讯》 CAS 2008年第4期483-487,共5页
目的:在大肠杆菌和毕赤酵母中表达人热激因子(hHSF)-1突变体hHSF190/2,并对其活性进行研究。方法:利用分子克隆技术分别构建了hHSF190/2的原核表达质粒pET45b-hHSF190/2和真核表达质粒pPICZaA-hHSF190/2,分别转入大肠杆菌BL21(DE3)pLys... 目的:在大肠杆菌和毕赤酵母中表达人热激因子(hHSF)-1突变体hHSF190/2,并对其活性进行研究。方法:利用分子克隆技术分别构建了hHSF190/2的原核表达质粒pET45b-hHSF190/2和真核表达质粒pPICZaA-hHSF190/2,分别转入大肠杆菌BL21(DE3)pLysS和毕赤酵母GS115进行诱导表达;经纯化除去杂蛋白后,采用蛋白免疫印迹、电泳迁移率变动分析和蛋白转导等方法研究表达产物的功能和活性。结果:hHSF190/2在2个系统中均得到有效表达,都具有与热激元件(HSE)结合的活性,但真核表达产物与HSE的结合能力明显高于原核表达产物;原核及真核系统表达的hHSF190/2都能激发热激蛋白(HSP)70的表达,但真核表达的hHSF190/2活性更高。结论:hHSF190/2有望成为有治疗作用的蛋白药物。 展开更多
关键词 激因子-1突变 大肠杆菌 毕赤酵母 表达 活性
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THDS-A热靶电压突变导致误报及漏报热轴的探析
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作者 王显红 姚波 《设备管理与维修》 2022年第13期58-60,共3页
针对THDS-A设备热靶电压突变误报铁路车辆轴承热轴问题,结合实际案例分析热靶电压突变的原因及热靶电压突变引起设备误报、漏报热轴的原理,实施改进措施并取得了良好效果。
关键词 THDS-A设备 靶电压突变 铁路车辆轴承温度
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高海拔地区冬季室内外辐射强度突变对人体热反应的影响
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作者 宋聪 王薇娜 +2 位作者 刘艳峰 桑豪伟 赵东雪 《建筑科学》 CSCD 北大核心 2024年第8期150-158,共9页
青藏高原太阳辐射较强,远高于同纬度低海拔地区。在室内外辐射突变环境下,高原人群对室内热环境的需求不同于室内稳态环境且没有准确描述。本文针对进藏和世居两种人群开展现场调研,并对高原室外辐射强度进行划分,获得两种人群的热反应... 青藏高原太阳辐射较强,远高于同纬度低海拔地区。在室内外辐射突变环境下,高原人群对室内热环境的需求不同于室内稳态环境且没有准确描述。本文针对进藏和世居两种人群开展现场调研,并对高原室外辐射强度进行划分,获得两种人群的热反应特征。结果表明:高原人群从室外不同辐射强度进入室内的热中性温度需求不同,且与稳态环境下室内人群热需求存在差异。进藏人群从室外不同辐射条件下进入室内的热中性温度分别为23.5℃(弱)、21℃(中)和17.9℃(强),其中强辐射组下的热中性温度要低于室内稳态环境(19.2℃),而弱和中辐射下热中性温度要高于室内稳态环境。因此,本研究结论可为青藏高原等强太阳辐射地区的建筑热环境调节策略提供参考。 展开更多
关键词 高海拔地区 辐射强度 突变环境 感觉 高原人群
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木聚糖酶XYNB分子中折叠股B1和B2间的疏水作用对酶热稳定性的影响 被引量:10
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作者 杨浩萌 姚斌 +6 位作者 罗会颖 张王照 王亚茹 袁铁铮 柏映国 伍宁丰 范云六 《生物工程学报》 CAS CSCD 北大核心 2005年第3期414-419,共6页
对来源于Streptomycesolivaceoviridis的高比活木聚糖酶XYNB进行同源建模,并结合嗜热木聚糖酶氮末端芳香族氨基酸疏水作用的结构分析,设计了XYNB的T11Y定点突变,观察XYNB分子中折叠股B1和B2的疏水作用对酶的热稳定性的影响。将突变酶XYN... 对来源于Streptomycesolivaceoviridis的高比活木聚糖酶XYNB进行同源建模,并结合嗜热木聚糖酶氮末端芳香族氨基酸疏水作用的结构分析,设计了XYNB的T11Y定点突变,观察XYNB分子中折叠股B1和B2的疏水作用对酶的热稳定性的影响。将突变酶XYNB′在毕赤酵母中表达,表达的XYNB′经纯化后与原酶XYNB(同样经毕赤酵母表达后纯化)进行酶学性质比较,结果表明,XYNB′的耐热性比XYNB有明显的提高,但最适温度与原酶一样为6 0℃。另外,XYNB′的最适pH、Km值及比活性均有一定的改变。实验证实了木聚糖酶XYNB的氮端芳香族氨基酸之间的疏水相互作用与其热稳定性相关,为进一步的结构与功能研究提供了优良的基因材料。 展开更多
关键词 木聚糖酶XYNB 定点突变 稳定性
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高性能印刷电路板用氰酸酯树脂研究进展 被引量:5
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作者 戴培邦 《绝缘材料》 CAS 北大核心 2010年第4期22-26,共5页
综述了国外高性能印刷电路板用氰酸酯树脂研究的新进展,包括催化剂对双氰酸酯单体发生环化三聚反应形成三嗪环的高度交联网络结构的大分子-三氮杂苯氰酸酯树脂的影响、氰酸酯树脂的增韧、氰酸酯树脂的湿/热性能、新型氰酸酯单体的合成... 综述了国外高性能印刷电路板用氰酸酯树脂研究的新进展,包括催化剂对双氰酸酯单体发生环化三聚反应形成三嗪环的高度交联网络结构的大分子-三氮杂苯氰酸酯树脂的影响、氰酸酯树脂的增韧、氰酸酯树脂的湿/热性能、新型氰酸酯单体的合成及其树脂的性能等。氰酸酯单体的固化受催化剂的影响,催化剂能促进固化反应,又能降低氰酸酯树脂的湿/热性能。氰酸酯树脂的增韧改性包括共混增韧改性和化学增韧改性。氰酸酯树脂表现出热突变效应和反转热效应的湿/热性能特征。新型氰酸酯单体的合成及其树脂的发展方向是进一步提高氰酸酯树脂的热性能和加工性能并降低其成本。 展开更多
关键词 氰酸酯树脂 三嗪环 增韧 反转效应 热突变
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理性设计盐桥构建伯克霍尔德菌脂肪酶热稳定突变体 被引量:1
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作者 刘艳如 赵丙春 +5 位作者 董盼盼 邱黎清 黄建忠 朱晓兰 王作镇 舒正玉 《微生物学报》 CAS CSCD 北大核心 2017年第7期1014-1025,共12页
【目的】借助蛋白质工程技术提高伯克霍尔德菌ZYB002脂肪酶LipA的热稳定性,以期更好地将其应用于工业生产中。【方法】利用YASARA、Fold X、Rosetta、Gromacs等生物信息学软件,构建1个脂肪酶Lip A的热稳定性提高的微型突变体电子文库;... 【目的】借助蛋白质工程技术提高伯克霍尔德菌ZYB002脂肪酶LipA的热稳定性,以期更好地将其应用于工业生产中。【方法】利用YASARA、Fold X、Rosetta、Gromacs等生物信息学软件,构建1个脂肪酶Lip A的热稳定性提高的微型突变体电子文库;通过对突变体的结构信息和自由能变化进行评估,筛选出潜在的有价值的突变体。继而利用基因定点突变技术,构建上述候选突变体的突变基因文库,通过实验筛选出热稳定性提高的脂肪酶LipA突变体。【结果】利用上述方法,从构建的20个脂肪酶LipA突变体中,筛选到热稳定性有显著提高的3个突变体LipA-Asn^(125)Asp、LipA-Asn^(125)Glu和LipA-Gln^(262)Glu。经55°C处理12 min后,上述3个突变体的T1250值较野生型分别提高4.0°C、5.5°C和4.4°C;在55°C下的半衰期较野生型分别提高了2.2倍、3.8倍和2.6倍。【结论】利用生物信息学软件,构建脂肪酶LipA突变体电子文库,结合蛋白质的结构信息,可以快速筛选到热稳定性提高的脂肪酶LipA突变体。 展开更多
关键词 伯克霍尔德菌 脂肪酶A 电子设计与筛选 盐桥 稳定性突变
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Expression and Thermal Stability Analysis of Peat1 and the 3 Deletion Mutants 被引量:2
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作者 李明勇 邱德文 +1 位作者 曾洪梅 杨秀芬 《Agricultural Science & Technology》 CAS 2008年第1期32-34,38,共4页
[Objective] The research aimed to reveal the functions of NAC and UBA domains in Peatl's thermal stability. [Method] Fusion expression vectors of Pearl protein and the 3 deletion mutants were constructed. The recombi... [Objective] The research aimed to reveal the functions of NAC and UBA domains in Peatl's thermal stability. [Method] Fusion expression vectors of Pearl protein and the 3 deletion mutants were constructed. The recombinant plasmids were induced by IPTG and the target proteins (Peatl, Peatl-△CD99,Peatl-△ND49 and Pearl-△ND108 )were expressed obtained by AKTA and its thermal stability was analyzed. [Result] The research found that 3 deletion mutants have good thermal stability like Pearl. [Conclusion] The research demonstrated that the coexistence of NAC or UBA domains is not necessary to thermal stability of Pearl protein , and they may give the protein particular stability structure seperately. 展开更多
关键词 Peatl Deletion mutant Thermal stability
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Analysis on the Variation Characteristics of Temperature in Anqing City and Urban Heat Island Effect 被引量:1
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作者 刘立群 朱月霞 顾卫 《Agricultural Science & Technology》 CAS 2011年第12期1913-1916,共4页
[Objective] The aim was to analyse the variation characteristics of temperature in Anqing City and urban heat island effect.[Method] Based on the observation data of temperature from Anqing Station,other surrounding m... [Objective] The aim was to analyse the variation characteristics of temperature in Anqing City and urban heat island effect.[Method] Based on the observation data of temperature from Anqing Station,other surrounding meteorological stations and local automatic meteorological stations in suburbs,the annual variation of temperature and regional consistency was analysed,then the abrupt change of annual average temperature was tested by Mann-Kendall test,finally the influences of urban heat island effect on temperature variation in Anqing Station were studied.[Result] Affected by station migration and urban construction,the annual average temperature increased significantly in Anqing Station from 1977 to 2009,and the rising was more prominent after the middle of the 1990s.Mann-Kendall test showed that the change of temperature in Anqing Station was obviously abrupt around 1993;because of the development of urbanization,average temperature in Anqing Station was 0.8 ℃ higher than that in suburbs,and the minimum temperature rose more remarkably.In addition,urban heat island effect was the strongest in spring,followed by summer and autumn,while it was the weakest in winter.[Conclusion] The effects of urbanization development on the temperature in Anqing City were understood through this research. 展开更多
关键词 TEMPERATURE Abrupt change Urban heat island effect
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Temperature Influences on the Expression of GFP Promoted by the Upstream Sequence of cpcB from Arthrospira platensis 被引量:1
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作者 LU Yongzhong ZHANG Xuecheng 《Journal of Ocean University of China》 SCIE CAS 2007年第3期244-248,共5页
In order to investigate the regulation mechanism of the phycocyanin gene,a series of functional analyses of the upstream sequence of cpcB gene from Arthrospira platensis were conducted in E. coli with green fluorescen... In order to investigate the regulation mechanism of the phycocyanin gene,a series of functional analyses of the upstream sequence of cpcB gene from Arthrospira platensis were conducted in E. coli with green fluorescent protein encoding gene(gfp) as the reporter. Results showed that the gfp gene could express at a high level under the promotion of the upstream sequence,suggesting the existence of some strong promoter elements in it. The expression of GFP was influenced by temperature. Higher temperature led to higher expression level. The bioinformatics analyses followed by mutation analyses on the secondary structure of translation ini-tiation region(TIR) revealed that RNA thermosensor might account for the temperature regulation. 展开更多
关键词 CYANOBACTERIUM flow cytometry mutation PHYCOCYANIN PROMOTER RNA thermosensor
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正显性热休克因子1突变体抑制6-OHDA诱导细胞死亡的研究
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作者 徐亮亮 侯永辉 邹江英 《中国生物工程杂志》 CAS CSCD 北大核心 2010年第1期25-28,共4页
热休克因子1是真核细胞应激反应时热休克蛋白表达的主要转录调控因子。它在非应激条件下被抑制性复合体抑制以非活化形式存在,只有在受到应激时才会暂时活化。通过基因突变得到的正显性突变体在不需要外界环境刺激的条件下就能激活细胞... 热休克因子1是真核细胞应激反应时热休克蛋白表达的主要转录调控因子。它在非应激条件下被抑制性复合体抑制以非活化形式存在,只有在受到应激时才会暂时活化。通过基因突变得到的正显性突变体在不需要外界环境刺激的条件下就能激活细胞内源性热休克蛋白的表达。环境神经毒素是引起帕金森病的一个重要因素,它们能够氧化损伤多巴胺能神经元,最终引起细胞死亡。Western blot和双荧光素酶检测证明,在SH-SY5Y细胞中转染正显性热休克因子1突变体能够明显上调HSP70的表达。并且通过检测细胞培养基中的乳酸脱氢酶的含量证明正显性热休克因子1突变体能够显著抑制神经毒素6-羟基多巴胺诱导的细胞死亡。这些结果表明,正显性热休克因子1突变体在帕金森病的防治方面可能具有潜在的应用前景。 展开更多
关键词 休克因子1 正显性休克因子1突变 休克蛋白 6-羟基多巴胺
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Specific VpU Codon Changes were Significantly associated with gp120 V3 Tropic Signatures in HIV-1 B-subtype
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作者 Salvatore Dimonte Muhammed Babakir-Mina +1 位作者 Stefano Aquaro Carlo-Federico Perno 《Virologica Sinica》 CAS CSCD 2012年第6期360-368,共9页
After infection and integration steps, HIV-1 transcriptions increase sharply and singly-spliced mRNAs are produced. These encode Env (gpl20 and gp41) and auxiliary proteins Vif, Vpr and VpU. The same localization wi... After infection and integration steps, HIV-1 transcriptions increase sharply and singly-spliced mRNAs are produced. These encode Env (gpl20 and gp41) and auxiliary proteins Vif, Vpr and VpU. The same localization within the unique structure of the mRNAs suggests that the VpU sequence prior to the Env could affect the Env polyprotein expression.The HIV-I infection process begins when the gpl20 subunit of the envelope glycoprotein complex interacts with its receptor(s) on the target cell. The V3 domain of gpl20 is the major determinant of cellular co-receptor binding. According to phenotypic information of HIVol isolates, sequences from the VpU to V3 regions (119 in R5- and 120 X4-tropic viruses; one per patient) were analysed. The binomial correlation phi coefficient was used to assess covariation among VpU and gpl20v3 signatures. Subsequently, average linkage hierarchical agglomerative clustering was performed. Beyond the classical V3 signatures (R5-viruses: SI1, E25D; X4-viruses: SllKR, E25KRQ), other specific V3 and novel VpU signatures were found to be statistically associated with co-receptor usage. Several statistically significant associations between V3 and VpU mutations were also observed. The dendrogram showed two distinct large clusters: one associated with R5-tropic sequences (bootstrap=0.94), involving: (a) H13NPv3, E25Dv3, Sllv3, T22Av3 and Q61Hvpu, (b) E25Av3 and L12Fvpu, (c) D44Evpu, R18Qv3 and D80Nvpu; and another associated with X4-tropic sequences (bootstrap=0.97), involving: (i) E25Iv3 and V10Avpu, (ii) 0-1insVvpc, H13Rv3, I46Lvpc, I30Mv3 and 60-62delvpu, (iii) SllKRv3 and E25KRQv3. Some of these pairs of mutations were encoded always by one specific codon. These data indicate the possible VpU mutational patterns contributing to regulation of HIV-I tropism. 展开更多
关键词 HIV VPU gpl20 V3 Mutations TROPISM Cluster analysis
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我国科学家率先发现儿童白内障致病基因
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《生物学教学》 北大核心 2003年第1期51-51,共1页
关键词 休克转录因子-4突变基因 发现 儿童 白内障 致病基因
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A THEORETICAL STUDY ON THE MULTIPLE EQUILIBRIA OF TROPICAL ATMOSPHERE AND THEIR RELATION TO THE ONSET OF THE SUMMER MONSOON
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作者 赵南 丁一汇 +1 位作者 Masaaki Takahashi 沈新勇 《Journal of Tropical Meteorology》 SCIE 2006年第2期130-138,共9页
Multiple equilibria and their stability in tropical atmosphere are investigated through β-plane barotropic models with consideration of heating and dissipation. We have derived the solutions of the model equations co... Multiple equilibria and their stability in tropical atmosphere are investigated through β-plane barotropic models with consideration of heating and dissipation. We have derived the solutions of the model equations corresponding to the multiple equilibria or the steady flows first, and then establish the criteria for the stability of steady flow by use of the Liapunov direct Method. When these criteria are applied to the solutions of equilibria obtained, stable flows, which are closely related to the different patterns of quasi-stationary circulation in the tropical region, are lbund. The configurations of these stable flows and the shift between two of them as season changes provide quite reasonable explanations to many fundarnental problems of tropical circulation features such as the catastrophe mechanism of the onset and the break-active cycle of the Asian summer monsoon. It fbllows that the onset or the abrupt transition of the Asian summer monsoon could be attributed to the multiple equilibrium property of the tropical circulation resulted from the advcetive nonlinearity, which provide another explanation among others. 展开更多
关键词 tropical atmosphere multiple equilibria abrupt transition Asian summer monsoon
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Weakening of the biennial relationship between Central American and equatorial South American rainfall in recent decades 被引量:1
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作者 WANG Lei WU Min-Min 《Atmospheric and Oceanic Science Letters》 CSCD 2017年第6期427-434,共8页
There is a rainfall variability biennial relationship between Central America (CA) and equatorial South America (ESA) over the tropical western hemisphere, which is known to have arisen due to the combined effects... There is a rainfall variability biennial relationship between Central America (CA) and equatorial South America (ESA) over the tropical western hemisphere, which is known to have arisen due to the combined effects of ENSO and tropical North Atlantic (TNA) SST. Here, the authors report that this biennial rainfall relationship between CA and ESA has weakened remarkably since 2000, with weakening in both in-phase and out-of-phase rainfall transitions. The observed decadal changes in the biennial relationship between CA and ESA rainfall can be attributed to changes in the effects of ENSO and TNA SST since 2000, which may be associated with more frequent occurrences of the central Pacific or'Modoki' type El Ni^o. The weakening of the association with ENSO for CA rainfall since 2000 might have given rise to the weakening of the in-phase rain transition from CA rainfall to the following ESA rainfall. The weakened linkage between boreal-winter ESA rainfall and the subsequent boreal-summer TNA SST since 2000 may have resulted in the weakening of the out- of-phase rainfall transition from boreal-winter ESA rainfall to the subsequent boreal-summer CA rainfall. 展开更多
关键词 Biennial variability tropicalrainfall ENSO tropicalNorth Atlantic twenty-firstcentury climate shift CentraAmerica equatorial SouthAmerica
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Difference in DNA sequences in SSU rDNA variable regions among pathogens isolated from different epidemic foci of visceral leishmaniasis in China
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作者 胡孝素 卜玲毅 +3 位作者 马莹 王雅静 敬保迁 易桃林 《Chinese Medical Journal》 SCIE CAS CSCD 2002年第10期17-19,143,共4页
To confirm the existence of point mutations in the SSU rDNA variable regions of 5 Leishmania donovani (L d ) isolates from different epidemic foci in China Methods Specific SSU rDNA fragments from nuclear DNA of 7... To confirm the existence of point mutations in the SSU rDNA variable regions of 5 Leishmania donovani (L d ) isolates from different epidemic foci in China Methods Specific SSU rDNA fragments from nuclear DNA of 7 Leishmania species/isolates were amplified by PCR and then cloned into pGEM R T Easy Vectors After that, the specific fragments were sequenced by an automated DNA sequencer Results Sequence analysis showed that the amplified DNA fragments of 7 Leishmania species/isolates were all 392 bp in length All 5 point mutations were located in two unique sequence blocks (UQ Ⅰ and UQ Ⅱ), and no insertions or deletions were found The identities of comparison of Leishmania in GeneBank were more than 98% Conclusion Five point mutations exist in the SSU rDNA variable region of 5 L d isolates from different epidemic foci of visceral leishmaniasis (VL) in China Sequence differences of the SSU rDNA variable region exist among L d isolates from different foci 展开更多
关键词 visceral leishmaniasis · Leishmania · point mutation · small subunit ribosomal DNA · polymerase chain reaction · cloning · sequence analysis · epidemic foci
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BALB/c小鼠口服幽门螺杆菌裂解物配伍dmLT佐剂诱导黏膜局部及系统性免疫应答 被引量:2
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作者 钟佑秀 陈敬 +3 位作者 刘钰 汤重发 魏博 刘梅影 《中华微生物学和免疫学杂志》 CAS CSCD 北大核心 2019年第4期298-304,共7页
目的观察口服免疫幽门螺杆菌(Hp)裂解物配伍黏膜佐剂双突变大肠埃希菌热不稳定毒素(double mutant heat-labile toxin,dmLT)在BALB/c小鼠中诱导抗Hp免疫保护效果,分析相关免疫应答特点。方法将SS1(Sydney strain 1)株Hp裂解物配伍佐剂d... 目的观察口服免疫幽门螺杆菌(Hp)裂解物配伍黏膜佐剂双突变大肠埃希菌热不稳定毒素(double mutant heat-labile toxin,dmLT)在BALB/c小鼠中诱导抗Hp免疫保护效果,分析相关免疫应答特点。方法将SS1(Sydney strain 1)株Hp裂解物配伍佐剂dmLT经口服免疫BALB/c小鼠后,进行幽门螺杆菌胃部活菌接种。对照组小鼠给予口服生理盐水,每只200μl。感染后6周检测幽门螺杆菌胃部定植量,采集血清、脾脏、肠系膜淋巴结、小肠、盲肠、粪便等样本进行相关免疫应答分析。结果抗原配伍佐剂免疫组小鼠与对照组相比较胃部幽门螺杆菌定植量降低;血清中检测到比对照组更强的特异性IgG抗体反应,IgG亚型主要以IgG1为主,且IgG1/IgG2a比值显著高于对照组;小肠、盲肠、粪便中均检测到较高的sIgA,小肠中最为显著,而对照组中均未有明显sIgA反应;脾和肠系膜淋巴结中IL-17+CD4+T比例与对照组相比较显著升高。结论口服免疫Hp裂解物配伍佐剂dmLT诱导黏膜局部及系统性免疫应答,增强BALB/c小鼠抗幽门螺杆菌感染,与显著增强的Th17免疫应答,以及Th细胞中Th2的极化相关,该结果为进一步评价dmLT作为黏膜佐剂用于幽门螺杆菌重组蛋白疫苗提供了实验资料。 展开更多
关键词 SS1裂解物 突变大肠埃希菌不稳定毒素(dmLT) BALB/c小鼠 免疫应答 幽门螺杆菌蛋白疫苗
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重组血型抗原结合黏附素的免疫原性初步探讨
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作者 王平 陈敬 +3 位作者 钟佑秀 刘钰 张燕斌 刘梅影 《微生物学免疫学进展》 CAS 2022年第6期41-46,共6页
目的构建幽门螺杆菌(Helicobacter pylori,Hp)血型抗原结合黏附素(blood group antigen-binding adhesin,babA)基因,表达纯化重组BabA蛋白;初步探索口服免疫BabA配伍双突变大肠埃希菌(E.coli)热不稳定毒素(double mutant heat-labile to... 目的构建幽门螺杆菌(Helicobacter pylori,Hp)血型抗原结合黏附素(blood group antigen-binding adhesin,babA)基因,表达纯化重组BabA蛋白;初步探索口服免疫BabA配伍双突变大肠埃希菌(E.coli)热不稳定毒素(double mutant heat-labile toxin,dmLT)佐剂在BALB/c小鼠中的免疫保护作用。方法从Hp SS1株基因组DNA中扩增babA编码基因,构建原核表达质粒pET28a-babA,转化入E.coli BL21(DE3)感受态细胞,IPTG诱导表达,His标签纯化。将纯化的BabA蛋白配伍dmLT免疫佐剂口服免疫BALB/c小鼠,生理盐水对照;末次免疫后2周小鼠眼眶静脉采血分离血清,分析特异性体液免疫应答;然后进行Hp胃部活菌感染,感染27周采集脾淋巴细胞进行细胞免疫分析并对小鼠胃部细菌定植量进行检测。结果重组质粒pET28a-babA基因序列正确;重组蛋白BabA以包涵体形式表达,相对分子质量56000,纯度为95.9%;重组BabA蛋白配伍dmLT佐剂口服免疫小鼠可诱导产生针对BabA的血清IgG抗体,抗体水平明显高于对照组(P=0.0018,P<0.05)。活菌感染后27周检测到分泌IL-4和IL-17细胞因子的脾淋巴细胞数量明显高于对照组(P=0.0022和0.0043,P均<0.05),小鼠胃部Hp定植量有降低趋势。结论重组BabA蛋白经原核表达镍柱纯化,配伍dmLT佐剂口服免疫BALB/c小鼠,其体液免疫和细胞免疫应答效果明显,对小鼠胃部Hp定植量有降低作用,可作为Hp蛋白疫苗的潜在候选抗原。 展开更多
关键词 血型抗原结合黏附素 突变大肠埃希菌不稳定毒素 佐剂 口服免疫 体液免疫 细胞免疫 蛋白疫苗
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