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Function and dysfunction of GEMIN5:understanding a novel neurodevelopmental disorder
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作者 Charles H.Nelson Udai B.Pandey 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第11期2377-2386,共10页
The recent identification of a neurodevelopmental disorder with cerebellar atrophy and motor dysfunction(NEDCAM)has resulted in an increased interest in GEMIN5,a multifunction RNA-binding protein.As the largest member... The recent identification of a neurodevelopmental disorder with cerebellar atrophy and motor dysfunction(NEDCAM)has resulted in an increased interest in GEMIN5,a multifunction RNA-binding protein.As the largest member of the survival motor neuron complex,GEMIN5 plays a key role in the biogenesis of small nuclear ribonucleoproteins while also exhibiting translational regulatory functions as an independent protein.Although many questions remain regarding both the pathogenesis and pathophysiology of this new disorder,considerable progress has been made in the brief time since its discovery.In this review,we examine GEMIN5 within the context of NEDCAM,focusing on the structure,function,and expression of the protein specifically in regard to the disorder itself.Additionally,we explore the current animal models of NEDCAM,as well as potential molecular pathways for treatment and future directions of study.This review provides a comprehensive overview of recent advances in our understanding of this unique member of the survival motor neuron complex. 展开更多
关键词 cerebellar atrophy gemin5 neurodevelopmental disorder neurological disease SMN complex
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MicroRNA生物合成通路中Gemin 3基因单核苷酸多态性与非霍奇金淋巴瘤风险及预后相关性 被引量:1
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作者 赵桂敏 刁兰萍 +3 位作者 刘丽宏 吴晓琳 高哲 高玉环 《中国实验血液学杂志》 CAS CSCD 北大核心 2017年第4期1053-1057,共5页
目的:评估miRNA生物合成过程中Gemin 3基因位点rs197412的单核苷酸多态性与患非霍奇金淋巴瘤(NHL)风险及预后的相关性。方法:在230名NHL患者组和120名健康对照者组中采用聚合酶链反应-连接酶检测反应进行MiR-SNP基因分型。利用Kaplan-Me... 目的:评估miRNA生物合成过程中Gemin 3基因位点rs197412的单核苷酸多态性与患非霍奇金淋巴瘤(NHL)风险及预后的相关性。方法:在230名NHL患者组和120名健康对照者组中采用聚合酶链反应-连接酶检测反应进行MiR-SNP基因分型。利用Kaplan-Meier法计算患者生存曲线,曲线之间的比较采用对数秩检验。多因素生存分析采用Cox比例风险模型进行。结果:rs197412基因分型在NHL组及对照组中分布无差异。患者携带rs197412 TT基因型比患者携带CC+CT基因型生存时间长(P=0.007)。此外,该rs197412 SNP也被确定为NHL预后的独立预测因子(相对危险度:2.138;95%可信区间:1.303-3.508;P=0.003)。结论:miRNA生物合成通路中Gemin 3基因位点rs197412的单核苷酸多态性与患NHL风险无关,但可能影响NHL的生存。 展开更多
关键词 MiR-SNP rs197412 gemin3 非霍奇金淋巴瘤
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EBNA3C与Gemin3两种蛋白形成复合物及相互作用的结构域
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作者 郭毅 唐艳君 赵楠 《微生物学杂志》 CAS CSCD 2014年第4期27-32,共6页
探讨EB病毒核抗原3C(EBNA3C)与Gemin3的相互结合及其作用区域。用Flag-EBAN3C与GFPGemin3共转染HEK 293细胞,采用免疫共沉淀、谷胱苷肽-S转移酶共沉淀及免疫荧光蛋白共存实验确定EBNA3C与Gemin3两种蛋白在体内、体外相互结合及相互作用... 探讨EB病毒核抗原3C(EBNA3C)与Gemin3的相互结合及其作用区域。用Flag-EBAN3C与GFPGemin3共转染HEK 293细胞,采用免疫共沉淀、谷胱苷肽-S转移酶共沉淀及免疫荧光蛋白共存实验确定EBNA3C与Gemin3两种蛋白在体内、体外相互结合及相互作用的结构域。EBNA3C与Gemin3两种蛋白在体内外相结合,二者通过各自的C端相互结合。EBNA3C与Gemin3两种蛋白形成稳定复合物。 展开更多
关键词 EBNa3C gemin3 结构域
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Simulation study of the losses and influences of geminate and bimolecular recombination on the performances of bulk heterojunction organic solar cells 被引量:1
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作者 朱键卓 祁令辉 +1 位作者 杜会静 柴莺春 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第10期584-590,共7页
We use the method of device simulation to study the losses and influences of geminate and bimolecular recombinations on the performances and properties of the bulk heterojunction organic solar cells. We find that a fr... We use the method of device simulation to study the losses and influences of geminate and bimolecular recombinations on the performances and properties of the bulk heterojunction organic solar cells. We find that a fraction of electrons(holes)in the device are collected by anode(cathode). The direction of the corresponding current is opposite to the direction of photocurrent. And the current density increases with the bias increasing but decreases as bimolecular recombination(BR)or geminate recombination(GR) intensity increases. The maximum power, short circuit current, and fill factor display a stronger dependence on GR than on BR. While the influences of GR and BR on open circuit voltage are about the same.Our studies shed a new light on the loss mechanism and may provide a new way of improving the efficiency of bulk heterojunction organic solar cells. 展开更多
关键词 bulk heterojunction organic solar cells LOSSES device simulation geminate recombination bi- molecular recombination
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EBNA3C combines with Gemin3 and up-regulates its expression
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作者 Qian Wang Dan Zhou Yi Guo 《中国现代医学杂志》 CAS CSCD 北大核心 2011年第6期697-708,共12页
Objective To investigate the combination of Epstein-Barr virus nuclear protein 3C (EBNA3C) with Gemin3 and its effect on Gemin3 expression. Methods Co-immunoprecipitation, GST pull-down and immunofluorescent assay wer... Objective To investigate the combination of Epstein-Barr virus nuclear protein 3C (EBNA3C) with Gemin3 and its effect on Gemin3 expression. Methods Co-immunoprecipitation, GST pull-down and immunofluorescent assay were used to determine the combination of EBNA3C and Gemin3 and their combining domain. Stable EBNA3C knockdown cell lines were made by lentivirus-delivered small hairpin RNA and then puromycin selection. Western blot was used to check the effect of EBNA3C on Gemin3 expression. Results EBNA3C and Gemin3 combined with each other in vivo and in vitro through their C-terminals. EBNA3C up-regulated Gemin3 gene expression. Conclusion EBNA3C forms complex with Gemin3 and up-regulates its expression. 展开更多
关键词 EBNa3C gemin3 gene expression regulation gene knock down
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The Behavior and Representation of Geminate Consonants in Moroccan Arabic
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作者 Ayoub Noamane 《宏观语言学》 2021年第1期53-83,共31页
The present paper explores the special behavior of geminate consonants in Moroccan Arabic vis-á-vis short consonants and consonant clusters.By way of comparison,it is shown that geminates exhibit properties that ... The present paper explores the special behavior of geminate consonants in Moroccan Arabic vis-á-vis short consonants and consonant clusters.By way of comparison,it is shown that geminates exhibit properties that are reminiscent of both unit structures and cluster structures.In particular,we reveal that geminates in MA demonstrate an inconsistent behavior in relation to the process of schwa epenthesis.In this context,we ask whether geminates get split up in MA,and when and how that happens.In order to characterize the patterning of geminates in MA,different phonological representations of geminates are examined against the variable behavior of geminates.On this basis,it is eventually suggested that geminates should be depicted as two root nodes that are underlyingly associated with a mora at the prosodic level. 展开更多
关键词 geminate behavior geminate representation Moraic Theory autosegmental phonology prosodic morphology Moroccan arabic
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连接基性质对松香基季铵盐Gemini表面活性剂的活性影响 被引量:8
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作者 韩世岩 李淑君 +2 位作者 赵颜颜 宋湛谦 方桂珍 《林产化学与工业》 EI CAS CSCD 北大核心 2012年第4期39-42,共4页
以四甲基乙二胺及三乙烯二胺为连接基制备了两种松香基季铵盐Gemini表面活性剂Ⅰ与Ⅱ,经表面活性分析:Ⅰ与Ⅱ的CMC值分别为1.42×10-4、9.7×10-4mol/L,γCMC为36.69、43.41 mN/m;乳化时间为16、10 min;降低表面张力的效率(pc20... 以四甲基乙二胺及三乙烯二胺为连接基制备了两种松香基季铵盐Gemini表面活性剂Ⅰ与Ⅱ,经表面活性分析:Ⅰ与Ⅱ的CMC值分别为1.42×10-4、9.7×10-4mol/L,γCMC为36.69、43.41 mN/m;乳化时间为16、10 min;降低表面张力的效率(pc20)计算值为4.2、3.2;HLB计算值皆约为14.45;Ⅰ与阴离子相溶性好,Ⅱ与阴离子相溶性较差。由实验分析结果探讨了连接基性质对松香基季铵盐Gem-ini表面活性剂的影响,结果表明:以柔性链为连接基的松香基季铵盐Gemini表面活性剂Ⅰ的活性优于以刚性链为连接基的松香基季铵盐Gemini表面活性剂Ⅱ。 展开更多
关键词 松香 季铵盐gemin表面活性剂 连接基团性质影响 活性
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MicroRNA生物合成相关基因在肝癌中的表达及其意义 被引量:1
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作者 闫兆伟 朱海涛 +5 位作者 董琼珠 周闯 张晓飞 任宁 叶青海 钦伦秀 《国际消化病杂志》 CAS 2013年第3期193-196,211,共5页
目的通过检测肝癌和癌旁组织中microRNA(miRNA)合成相关基因的mRNA表达,分析其与肝癌恶性行为的关系。方法运用实时荧光定量聚合酶链反应(RT-PCR)技术检测肝癌组织及其配对癌旁组织中miRNA生物合成相关基因的mRNA表达水平,比较分析其表... 目的通过检测肝癌和癌旁组织中microRNA(miRNA)合成相关基因的mRNA表达,分析其与肝癌恶性行为的关系。方法运用实时荧光定量聚合酶链反应(RT-PCR)技术检测肝癌组织及其配对癌旁组织中miRNA生物合成相关基因的mRNA表达水平,比较分析其表达水平差异及其与肝癌预后的关系。结果 RT-PCR结果显示,与相应的癌旁组织相比,肝癌组织中细胞核内miRNA生物合成相关基因Drosha、DGCR8、DBR1、ADAR、Exportin 5的mRNA表达水平显著升高(P<0.0001),而细胞质内miRNA生物合成相关基因Dicer、AGO2、GEMIN3、GEMIN4的mRNA表达水平显著下降(P<0.0001)。肝癌组织中DBR1和Exportin 5 mRNA高表达患者的总生存率高于低表达患者(P<0.05),癌旁组织中DGCR8mRNA高表达患者的总生存率高于低表达患者(P<0.05)。结论 Dicer的表达可能在肝癌发生发展过程中起重要作用。DBR1、Exportin 5和DGCR8可以作为肝癌治疗的潜在干预靶点。 展开更多
关键词 肝细胞癌 MICRORNa DROSHa DGCR8 EXPORTIN 5 DICER aGO2 gemin3 gemin4 DBR1 aDaR
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EB病毒核抗原3C提高Gemin3基因的表达 被引量:1
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作者 郭毅 孔繁明 赵楠 《中国医科大学学报》 CAS CSCD 北大核心 2012年第6期497-500,共4页
目的探讨EB病毒核抗原(EBNA)3C对Gemin3基因表达的影响。方法共转染EBNA3C和Gemin3基因至HEK293细胞。依靠慢病毒载体介导发卡RNA干涉敲减EBNA3C基因的表达,并经嘌呤霉素筛选获得稳定的EBNA3C低表达细胞系,采用Western blot检测EBNA3C对... 目的探讨EB病毒核抗原(EBNA)3C对Gemin3基因表达的影响。方法共转染EBNA3C和Gemin3基因至HEK293细胞。依靠慢病毒载体介导发卡RNA干涉敲减EBNA3C基因的表达,并经嘌呤霉素筛选获得稳定的EBNA3C低表达细胞系,采用Western blot检测EBNA3C对Gemin3蛋白表达的影响。结果 Gemin3基因的表达随着EBNA3C表达量的增加而增加,呈剂量依赖性,在EBNA3C基因敲减细胞中Gemin3的表达减少。结论 EBNA3C可提高Gemin3基因表达水平。 展开更多
关键词 EB病毒核抗原3C gemin3 基因表达调控 基因敲减
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Gemin3抑制p53介导的细胞凋亡(英文)
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作者 王倩 张晓光 +1 位作者 郭毅 尚红 《中国现代医学杂志》 CAS CSCD 北大核心 2013年第18期1-11,共11页
目的探讨Gemin3基因表达在细胞增殖中的作用及其途径。方法采用免疫共沉淀、谷胱苷肽-S转移酶共沉淀实验确定Gemin3与p53两种蛋白在体内、体外相互结合及相互作用的结构域。荧光素酶报告基因检测转染Gemin3基因对p53基因的影响,依靠慢... 目的探讨Gemin3基因表达在细胞增殖中的作用及其途径。方法采用免疫共沉淀、谷胱苷肽-S转移酶共沉淀实验确定Gemin3与p53两种蛋白在体内、体外相互结合及相互作用的结构域。荧光素酶报告基因检测转染Gemin3基因对p53基因的影响,依靠慢病毒载体介导发卡RNA干涉敲减Gemin3基因的表达并经嘌呤霉素筛选获得稳定的Gemin3低表达细胞系,实时PCR检测Gemin3敲减对p53及其下游基因在转录水平的影响,流式细胞检测Gemin3敲减对细胞增殖的影响。结果 Gemin3的C端与p53的中部DNA结合部位相互结合,Gemin3在转录水平抑制p53基因的表达,敲减Gemin3基因的表达导致细胞凋亡的增加。结论 Gemin3与p53相互结合并通过抑制p53的表达促进细胞的增殖。 展开更多
关键词 gemin3 P53 凋亡 基因敲减
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Bilateral double teeth—A case report
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作者 Sandip Kulkarni S. M. Meghana Monica Yadav 《Open Journal of Stomatology》 2012年第4期366-368,共3页
Developmental anomalies can occur as a result of conjoining or twinning defects. These include fusion, gemination and concrescence. Such anomalies occur more often in the deciduous than in the permanent dentition and ... Developmental anomalies can occur as a result of conjoining or twinning defects. These include fusion, gemination and concrescence. Such anomalies occur more often in the deciduous than in the permanent dentition and only a few cases involving molar and premolar teeth have been reported in the literature. Cases of bilateral double teeth are less frequent than unilateral and prevalence seems to be higher in the anterior region. The present article is a rare case report of simultaneous occurrence of double teeth in permanent dentition involving the mandibular premolar-molar teeth in a 45-year-old male patient. Clinical observation along with radiographic examination was used to arrive at a diagnosis. 展开更多
关键词 DEVELOPMENTaL aNOMaLY FUSION gemination ENDODONTIC Treatment
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二聚阳离子表面活性剂改性蒙脱土的制备和表征 被引量:5
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作者 陈海群 王海靖 +3 位作者 朱俊武 杨绪杰 陆路德 汪信 《精细化工》 EI CAS CSCD 北大核心 2004年第7期489-491,495,共4页
合成了二聚阳离子表面活性剂GeminiC12,用核磁共振氢谱(1HNMR)表征了它的结构,并用它作为有机插层剂应用于蒙脱土的改性处理。红外光谱(FTIR)、热重分析(TGA)表明,GeminiC12已插层到蒙脱土片层间。X射线粉末衍射(XRD)表明,插层后蒙脱土... 合成了二聚阳离子表面活性剂GeminiC12,用核磁共振氢谱(1HNMR)表征了它的结构,并用它作为有机插层剂应用于蒙脱土的改性处理。红外光谱(FTIR)、热重分析(TGA)表明,GeminiC12已插层到蒙脱土片层间。X射线粉末衍射(XRD)表明,插层后蒙脱土层间距从1 19nm增加到3 8nm,是十六烷基三甲基溴化铵(CTAB)处理效果的两倍。沉降实验表明,改性后蒙脱土在苯乙烯和石蜡中形成凝胶体系,表现出很好的相容性和分散性,这种改性效果优于目前常用的CTAB处理效果,更有利于聚合物或其单体进入蒙脱土层间形成纳米复合材料。 展开更多
关键词 二聚阳离子表面活性剂 有机蒙脱土 geminiC12 纳米复合材料
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Structure-Property Relationship Analysis of D-Penicillamine-Derivedβ-Polythioesters with Varied Alkyl Side Groups 被引量:1
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作者 Chun-Yan Lyu Wei Xiong +1 位作者 Er-Qiang Chen Hua Lu 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2023年第10期1555-1562,共8页
The ring-opening polymerization of heterocyclic monomers and the reversed ring-closing depolymerization of corresponding polymers with neutral thermodynamics are broadly explored to establish a circular economy of nex... The ring-opening polymerization of heterocyclic monomers and the reversed ring-closing depolymerization of corresponding polymers with neutral thermodynamics are broadly explored to establish a circular economy of next-generation plastics.Polythioesters(PTEs),analogues of polyesters,are emerging materials for this purpose due to their high refractive index,high crystallinity,dynamic property and responsiveness.In this work,we synthesize and polymerize a series of D-penicillamine-derivedβ-thiolactones(NRPenTL)with varied side chain alkyl groups,and study the structure-property relationship of the resulting polymers.The obtained PTEs exhibit tunable glass transition temperature in a wide range of 130–50℃,and melting temperature of 90–105℃.In addition,copolymerizations of monomers with different side chains are effective in modulating material properties.The obtained homo and copolymers can be fully depolymerized to recycle monomers.This work provides a robust molecular platform and detailed structure-property relationship of PTEs with potential of achieving sustainable plastics. 展开更多
关键词 β-Polythioesters geminal dimethyl Structure-property relationship Chemical recycling to monomers
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GX15-070进入临床试验
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作者 黄敏燕 《国外药讯》 2005年第2期19-19,共1页
位于加拿大蒙特利尔的Gemin X生物科技公司,已经开始了它的GX15-070(Ⅰ)的Ⅰ期临床试验。(Ⅰ)是一个BCL-2蛋白小分子抑制剂。在公开标签、剂量递增试验中将评估多种剂量(Ⅰ)对实体瘤患者的安全性和耐受性及(Ⅰ)的药效学和药代动力学特征。
关键词 GX15-070 临床试验 加拿大 gemin X生物科技公司 抗肿瘤药
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Off-diagonal long-range order of the wave function in terms of the alternate molecular bonding geminals
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作者 吕文彩 孙家钟 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2000年第4期467-474,共8页
It is shown that in the quantum structural approach to high-Tc superconductivity, the wave function in terms of the alternate molecular bonding geminals possesses off-diagonal long-range order (ODLRO).
关键词 alternate molecular bonding geminals quantum structural approach off-diagonal long-range order
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Gemin3基因通过抑制p53表达阻碍细胞凋亡 被引量:2
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作者 郭毅 张晓光 +2 位作者 赵楠 李天人 李慧 《中华肿瘤杂志》 CAS CSCD 北大核心 2011年第11期810-815,共6页
目的探讨Gemin3基因表达在细胞凋亡中的作用及途径。方法采用免疫共沉淀、谷胱甘肽-S转移酶共沉淀实验确定Gemin3与p53两种蛋白在体内、体外相互结合及相互作用的结构域。荧光素酶报告基因检测转染Gemin3基因对p53基因的影响,依靠慢病... 目的探讨Gemin3基因表达在细胞凋亡中的作用及途径。方法采用免疫共沉淀、谷胱甘肽-S转移酶共沉淀实验确定Gemin3与p53两种蛋白在体内、体外相互结合及相互作用的结构域。荧光素酶报告基因检测转染Gemin3基因对p53基因的影响,依靠慢病毒载体介导小干扰RNA敲低Gemin3基因的表达,并经嘌呤霉素筛选获得稳定的Gemin3低表达细胞系,实时定量PCR检测Gemin3敲低对p53及其下游基因在转录水平的影响,流式细胞术检测Gemin3敲低对细胞凋亡的影响。结果Gemin3的C端与p53的中部DNA部位相互结合。将p53报告基因、p53蛋白基因以及逐渐增量的Gemin3基因共转染Saos-2细胞,随着Gemin3质粒转染浓度的增高,p53介导的报告基因表达水平逐渐降低,Gemin3在转录水平抑制p53基因的表达。实时定量PCR结果显示,与对照细胞比较,Gemin3敲低细胞中,p53、p21和BaxmRNA的表达水平明显增高。Western blot检测结果显示,Gemin3敲低细胞中,p53的表达明显升高。流式细胞术检测结果显示,敲低Gemin3基因的表达导致细胞凋亡的增加。结论Gemin3与p53相互结合并通过抑制p53的表达阻碍细胞凋亡。 展开更多
关键词 基因 gemin3 基因 p53 细胞凋亡 RNa干扰
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MicroRNA生物合成相关蛋白基因SNP与结直肠癌患者预后关系 被引量:1
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作者 吴忱思 郭占军 +1 位作者 赵宇飞 赵乐 《中华肿瘤防治杂志》 CAS 北大核心 2020年第13期1070-1074,共5页
目的 MicroRNA (miRNA)生物合成相关蛋白基因单核苷酸多态性(single-nucleotide polymorphisms,SNPs与多种肿瘤发生及预后相关,其与结直肠癌预后的关系少有报道。本研究通过对其基因多态位点进行分型分析,结合临床因素,研究其与结直肠... 目的 MicroRNA (miRNA)生物合成相关蛋白基因单核苷酸多态性(single-nucleotide polymorphisms,SNPs与多种肿瘤发生及预后相关,其与结直肠癌预后的关系少有报道。本研究通过对其基因多态位点进行分型分析,结合临床因素,研究其与结直肠癌患者预后的关系。方法选取2007-01-29-2008-12-15河北医科大学第四医院普外科住院治疗的126例结直肠癌手术患者作为研究对象。采用聚合酶链反应-连接酶检测法(polymerase chain reaction-1igase detection reaction,PCR-LDR)对结直肠癌患者的6个miRNA生物合成相关蛋白的基因多态位点进行分型,并运用Kaplan-Meier法、Log-rank检验和Cox比例风险模型等分析其与结直肠癌预后的关系。结果 Kaplan-Meier法和Logrank检验结果显示,GEMIN4基因的rs2740348CC基因型(P=0.028)和rs3742330AA基因型(P=0.016)与结直肠癌患者术后生存时间有关。Cox比例风险模型结果显示,rs2740348多态位点SNP与结直肠癌患者预后密切相关(95%CI:1.022~7.525,RR=2.774,P=0.045)。结论 GEMIN4基因的rs2740348位点为与结直肠癌患者预后相关的独立危险因素。 展开更多
关键词 gemin4基因 结直肠癌 microRNa生物合成相关蛋白 预后
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Influence of steric and intramolecular inductive effects on the variable trends in R-X (R=Alkyl) bond dissociation energy 被引量:4
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作者 CAO ChenZhong School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China 《Science China Chemistry》 SCIE EI CAS 2009年第7期943-951,共9页
The question "why are the variation trends of R-X bond dissociation energy different?" is answered. The R-X bond dissociation energy (BDE) may be influenced by three main factors: the C-X intrinsic bond ener... The question "why are the variation trends of R-X bond dissociation energy different?" is answered. The R-X bond dissociation energy (BDE) may be influenced by three main factors: the C-X intrinsic bond energy, the 1,3 geminal repulsion, and the intramolecular charge-induced dipole. In the presence of atom X, the variation trend of BDE in R-X (R= Me, Et, i-Pr, t-Bu) is dominated by two factors, the 1,3 geminal repulsion and the intramolecular charge-induced dipole. The former decreases the R-X BDE, and the latter either increases or decreases the R-X BDE. For the series of R-X with the R-C bond (such as R-Me, R-CH == CH2, R-C≡CH, and R-CN), the 1,3 geminal repulsion decreases the R-X BDE, and the variation trends of R-C BDE decrease from Me to t-Bu. As regards the series of R-X (such as R-H, R-BH2, and R-SiH2) in which the electronegativity of atom X is smaller than that of the carbon atom, the above two factors decrease the R-X BDE, and the variation trends of the R-X BDE decrease from Me to t-Bu. As to the series of R-X (such as R-F, R-OH, R-Cl, R-Br, R-I, and R-NH2) in which the electronegativity of atom X is larger than that of the carbon atom, the 1,3 geminal repulsion decreases the R-X BDE, while the intramolecular charge-induced dipole increases the R-X BDE. In this case, the variation trends of R-X BDE depend on the competition of the two factors. As a result, some of them (e. g., R-F, R-OH) increase from Me to t-Bu, some (e. g., R-I) decrease from Me to t-Bu, and some (e. g., R-Br) change very little. 展开更多
关键词 bond DISSOCIaTION energy charge-induced DIPOLE geminal REPULSION ionic configuration
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An Efficient Synthesis of [1,2,4]Triazolo[3,2-d][1,5]benzoxazepin-2-thiones, a Kind of Novel Tricyclic O,N-Heterocycles
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作者 李诤 孟青青 +1 位作者 王全瑞 陶凤岗 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2004年第3期290-295,共6页
A series of novel tricyclic O,N-heterocycles, [1,2,4]triazolo[3,2-d][1,5]benzoxazepin-2-thiones 7 were achieved via acid-induced ring closure of the geminal arylazo isothiocyanate compounds 5 which were derived from s... A series of novel tricyclic O,N-heterocycles, [1,2,4]triazolo[3,2-d][1,5]benzoxazepin-2-thiones 7 were achieved via acid-induced ring closure of the geminal arylazo isothiocyanate compounds 5 which were derived from substituted chroman-4-ones, followed by feasible ring expansion with simultaneous insertion of the nitrogen atom into the carbon skeleton. The X-ray crystal structure of 7d was also described. 展开更多
关键词 geminal arylazo isothiocyanate ring closure REaRRaNGEMENT [1 2 4]triazolo[3 2-d][1 5]benzoxazepin-2-thiones
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