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小尾寒羊高繁殖力候选基因BMP15和GDF9的研究 被引量:95
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作者 储明星 桑林华 +2 位作者 王金玉 方丽 叶素成 《Acta Genetica Sinica》 SCIE CAS CSCD 北大核心 2005年第1期38-45,共8页
以控制Belclare和Cambridge绵羊高繁殖力的骨形态发生蛋白 15 (bonemorphogeneticprotein 15 ,BMP15 )基因和生长分化因子 9(growthdifferentiationfactor 9,GDF9)基因为候选基因 ,采用PCR RFLP技术检测BMP15基因和GDF9基因在高繁殖力... 以控制Belclare和Cambridge绵羊高繁殖力的骨形态发生蛋白 15 (bonemorphogeneticprotein 15 ,BMP15 )基因和生长分化因子 9(growthdifferentiationfactor 9,GDF9)基因为候选基因 ,采用PCR RFLP技术检测BMP15基因和GDF9基因在高繁殖力绵羊品种 (小尾寒羊、湖羊 )以及低繁殖力绵羊品种 (多赛特羊、特克塞尔羊、德国肉用美利奴羊 )中的单核苷酸多态性 ,同时研究这两个基因对小尾寒羊高繁殖力的影响。结果表明 :在 5个绵羊品种中都没有检测到GDF9基因的G8突变 (C→T) ,也没有检测到BMP15基因的B4突变 (G→T)。高繁殖力的小尾寒羊在BMP15基因编码序列第 718位碱基处发生了与Belclare绵羊和Cambridge绵羊相同的B2突变 (C→T) ,而其余 4个绵羊品种则没有发生这种突变。对于BMP15基因的B2突变 ,在小尾寒羊中检测到AA、AB两种基因型 ,A等位基因频率为 0 734,B等位基因频率为 0 2 6 6。小尾寒羊与其余 4个绵羊品种间B2突变基因型分布差异极显著 (P <0 0 0 1)。突变杂合基因型 (AB)小尾寒羊平均产羔数比野生纯合基因型 (AA)多 0 6 2只 (P <0 0 1)。研究结果表明 ,BMP15B2突变对小尾寒羊高繁殖力影响作用十分明显 。 展开更多
关键词 绵羊 高繁殖力 候选基因法 骨形态发生蛋白15基因 生长分化因子9基因 PCR—RFLP
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不同绵羊群体BMP15基因多态性检测及序列分析 被引量:2
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作者 任立坤 刘月琴 +3 位作者 张英杰 杨少华 王红娜 董李学 《黑龙江畜牧兽医》 CAS 北大核心 2012年第4期36-38,共3页
为了检测在小尾寒羊、无角陶赛特羊及陶×寒F1、F2代中骨形态发生蛋白15(BMP15)基因的单核苷酸多态性,试验采用PCR-RFLP、PCR-SSCP方法进行检测。结果表明:在小尾寒羊、无角陶赛特、陶×寒F1和F2代群体中均未检测到BMP15基因,... 为了检测在小尾寒羊、无角陶赛特羊及陶×寒F1、F2代中骨形态发生蛋白15(BMP15)基因的单核苷酸多态性,试验采用PCR-RFLP、PCR-SSCP方法进行检测。结果表明:在小尾寒羊、无角陶赛特、陶×寒F1和F2代群体中均未检测到BMP15基因,编码序列第718位碱基处发生了FecXG(B2)突变,与贝尔克莱绵羊和剑桥绵羊相同,说明BMP15 B2突变在这4个绵羊群体中的自然发生率非常低。 展开更多
关键词 繁殖力 候选基因法 骨形态发生蛋白15(BMP15)基因 PCR-SSCP PCR-RFLP
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高水热稳定有序介孔Al-SBA-15材料的优化合成及表征 被引量:4
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作者 徐倩 董朝阳 +4 位作者 石国亮 潘大海 于峰 陈树伟 李瑞丰 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2015年第12期2355-2363,共9页
借助无机铝盐自水解所产生的弱酸性环境,通过改变水热处理温度及无机铝盐的引入种类和引入量来调控合成体系中Al—OH及材料孔壁中Si—OH的相对含量,在不引入矿物质强酸的条件下,一步合成了具有高Al引入量且孔壁硅、铝物种达到原子水平... 借助无机铝盐自水解所产生的弱酸性环境,通过改变水热处理温度及无机铝盐的引入种类和引入量来调控合成体系中Al—OH及材料孔壁中Si—OH的相对含量,在不引入矿物质强酸的条件下,一步合成了具有高Al引入量且孔壁硅、铝物种达到原子水平均匀分散的Al-SBA-15介孔材料.表征结果表明,当以硝酸铝为铝源,水热处理温度和投料硅铝比分别为140℃和10时,所得样品具有高度有序的二维六方介孔结构及较高的水热稳定性,在经800℃高温水蒸气处理2 h后,其介孔比表面积和孔体积仅分别降低了18.82%和16.67%.此外,骨架Al的引入使所得样品同时具有B酸和L酸中心,且具有相对较强的酸性,在异丙苯催化裂化反应中表现出明显活性. 展开更多
关键词 介孔材料 Al-SBA-15 水热稳定性 水热嫁接
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An improved ion-exchange/diffusion method for ~(15)N isotope tracing analysis of nitrate in surface waters from watersheds 被引量:4
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作者 Weiqi Chen Weicai Chen Huanhuan Rao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第5期784-788,共5页
An improved method,suitable for collecting nitrate from surface waters in the watershed for 15 N isotope tracing analysis,was developed on the basis of the anion exchange coupled with diffusion through systematic simu... An improved method,suitable for collecting nitrate from surface waters in the watershed for 15 N isotope tracing analysis,was developed on the basis of the anion exchange coupled with diffusion through systematic simulation and comparison experiments.The results showed that the nitrate could be separated and enriched from the waters efficiently by using the improved method.Being simple and practical in operation principle and procedures,cost-economic,and highly efficient in nitrate separation/enrichment,the method met the requirements of δ 15 N mass spectrum analysis and would lay a foundation for the application of 15 N isotope tracing approach to the research on non-point source pollution in watershed. 展开更多
关键词 anion exchange and diffusion NITRATE 15N tracing approach surface water WATERSHED
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两种固体席夫碱^(15)N化学屏蔽研究中的分子内氢键作用(英文)
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作者 郑广 湛昌国 +2 位作者 沈联芳 叶朝辉 WebbG.A 《波谱学杂志》 CAS CSCD 北大核心 1998年第4期341-346,共6页
应用量子化学基本原理,对两种固体化合物席夫碱类的15N化学位移的分子内氢键效应进行了研究.为简化计算,本文在计算过程中采用一种简化模型.其分子几何结构参数采用优化值.本文结果表明:理论值成功地再现了两种固体化合物的1... 应用量子化学基本原理,对两种固体化合物席夫碱类的15N化学位移的分子内氢键效应进行了研究.为简化计算,本文在计算过程中采用一种简化模型.其分子几何结构参数采用优化值.本文结果表明:理论值成功地再现了两种固体化合物的15N化学屏蔽值,证实了15N在分子内氢键形成过程中的屏蔽行为.本文证实当有分子内氢键形成时(大约为0.2nm),15N化学位移向高频区大约移动50ppm.本文结果对理论上定量估计氢键强度可能会有重要作用. 展开更多
关键词 化学位移 席夫碱 氢键 15 量子化学
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陶庄矿区深井水位的发震信息
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作者 孟晓花 《防灾科技学院学报》 2011年第3期51-54,共4页
利用山东省枣庄市陶庄煤矿区鲁15井水位观测资料,采用多道Weiner滤波方法研究其中所隐含的孕震信息,结论是没有明显的矿震中期前兆异常,临震前兆异常明显,每次矿震前都有水位的短临变化。
关键词 矿震 15井水位资料 多道Weiner滤波方法 孕震信息
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Appraisal of the Production-Oriented Approach: An Introduction 被引量:4
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作者 濮实 《Chinese Journal of Applied Linguistics》 SCIE 2017年第4期452-453,共2页
The production-oriented approach (POA) has been developed over a decade. It is driven by the need to improve English classroom instruction for university students in China (Wen, 2016). It is also motivated by the ... The production-oriented approach (POA) has been developed over a decade. It is driven by the need to improve English classroom instruction for university students in China (Wen, 2016). It is also motivated by the aspiration to enhance the quality of foreign language education in other similar pedagogical contexts outside China. A volume of research has been done by Wen Qiufang and her research team, to formulate the theory of POA and to test its effectiveness in classroom pedagogy (e.g. Wen, 2016, 2015; Yang, 2015; Zhang, 2015). At the moment, the POA is still at an early stage of theory building and almost all empirical research is done in the Chinese context. In order to improve the quality of this theory and to make it intelligible to the international academic community, a one-day symposium was held in Beijing Foreign Studies University on May 15, 2017. The symposium was entitled 'The first international forum on innovative foreign language education in China: Appraisal of the POA'. In the forum, leading experts in applied linguistics were invited to discuss the strengths and weaknesses of the POA and the directions for its future development. The symposium was the first attempt for the POA research team to discuss its latest work with international scholars. This Viewpoint section collects the responses of four experts who participated in the symposium, listed in alphabetical order. The collection of articles covers three topics related to the POA: its pedagogical application, its use for teacher training, and its research. Alister Cumming is Professor Emeritus and the former Head of the Centre for Educational Research on Languages and Literacies, University of Toronto, Canada. His article focuses primarily on POA research as an exemplary case of design-based research. Rod Ellis is Research Professor in the School of Education at Curtin University, Australia. He discusses POA in terms of pedagogy, teacher training and research, with both critiques and constructive suggestions. Paul Kei Matsuda is Professor of English and Director of Second Language Writing at Arizona State University, the writed states. He responds to POA from the perspective of an expert researcher and teacher of L2 writing. Charlene Polio is Professor and Associate Chair in the Department of Linguistics & Germanic, Slavic, Asian & African Languages atMichigan State University, the writed states. She conceptualises POA as a useful method to address some issues in pre-service teacher development. Overall, the articles in this section are insightful and reader-friendly. They are not only useful for the development of POA in particular, but may also be valuable to a broad range of researchers as they touch upon pertaining issues, as well as emerging topics, in the field of applied linguistics. We therefore find it necessary to make them accessible to a wide readership. 展开更多
关键词 The production-oriented approach (POA) has been developed over a decade. It is driven by the need to improve English classroom instruction for university students in China (Wen 2016). It is also motivated by the aspiration to enhance the quality of foreign language education in other similar pedagogical contexts outside China. A volume of research has been done by Wen Qiufang and her research team to formulate the theory of POA and to test its effectiveness in classroom pedagogy (e.g. Wen 2016 2015 Yang 2015 Zhang 2015). At the moment the POA is still at an early stage of theory building and almost all empirical research is done in the Chinese context. In order to improve the quality of this theory and to make it intelligible to the international academic community a one-day symposium was held in Beijing Foreign Studies University on May 15 2017. The symposium was entitled 'The first international forum on innovative foreign language education in China: Appraisal of the POA'. In the forum leading experts in applied linguistics were invited to discuss the strengths and weaknesses of the POA and the directions for its future development. The symposium was the first attempt for the POA research team to discuss its latest work with international scholars. This Viewpoint section collects the responses of four experts who participated in the symposium listed in alphabetical order. The collection of articles covers three topics related to the POA: its pedagogical application its use for teacher training and its research. Alister Cumming is Professor Emeritus and the former Head of the Centre for Educational Research on Languages and Literacies University of Toronto Canada. His article focuses primarily on POA research as an exemplary case of design-based research. Rod Ellis is Research Professor in the School of Education at Curtin University Australia. He discusses POA in terms of pedagogy teacher training and research with both critiques and constructive suggestions. Paul Kei Matsuda is Professor of English and Director of Second Language Writing at Arizona State University the writed states. He responds to POA from the perspective of an expert researcher and teacher of L2 writing. Charlene Polio is Professor and Associate Chair in the Department of Linguistics Germanic Slavic Asian African Languages atMichigan State University the writed states. She conceptualises POA as a useful method to address some issues in pre-service teacher development. Overall the articles in this section are insightful and reader-friendly. They are not only useful for the development of POA in particular but may also be valuable to a broad range of researchers as they touch upon pertaining issues as well as emerging topics in the field of applied linguistics. We therefore find it necessary to make them accessible to a wide readership.
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