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1.
 同型半胱氨酸/半胱氨酸是体内的含硫氨基酸,近年来提出它们可以诱导血管平滑肌细胞的增殖,是心血管病的一个新的独立的危险因子.但其机制尚不了解,本研究目的在于克隆同型半胱氨酸/半胱氨酸诱导的新基因.应用差异显示即RNAmapping的方法,从半胱氨酸诱导的大鼠血管平滑肌细胞中,寻找有差异的条带,克隆新的cDNA.结果分离出7种上调和4种下调cDNA,并且发现其中有4个是至今尚未发现的新的cDNA.应用Northernblot分析,这4个新的mRNA其长度分别为5.0、2.0、1.8和2.2kb.它们可能在血管平滑肌细胞增殖和心血管病的发病中具有重要意义.  相似文献
2.
中国人MTHFR基因多态性与神经管畸形遗传易感性   总被引:15,自引:3,他引:12       下载免费PDF全文
朱慧萍  李竹 《遗传》2000,22(4):236-238
目的:应用分子生物学方法进行遗传流行病学研究, 探讨MTHFR基因多态性在神经管畸形的遗传易感性中的作用。方法:应用PCR?RFLP方法检测MTHFR热敏感性基因型;对18个NTD核心家庭进行以父母为对照的病例对照研究,计算TDT和HHRR;另外对31例NTD胎儿和62例正常成年人进行的成组病例对照研究,计算MTHFR纯合突变对NTD的比值比。结果:核心家庭分析结果:比值比OR=3.2,95%CI=1.120~11.169;TDT(χ2)=5.762,P<0.05,HHRR(成组χ2)=6.727,P<0.05;胎儿MTHFR纯合突变对NTD的相对危险度OR=3?21,P<0?05。结论:研究结果说明,突变等位基因在神经管畸形核心家庭中存在突变基因(T)的遗传失衡现象,胎儿MTHFR基因第677位核苷酸的多态性是中国人NTD遗传易感性因素之一。 Abstract:The objective of the study is to clarify the effect of MTHFR thermolabile polymorphism on genetic susceptibility of NTD in Chinese population.MTHFR genotypes were detected using PCR-RFLP analysis; 18 NTD nuclear families were analysed as case-parental control study,from which Transmitted Disequillibrium Test(TDT) and Haplotype-based Haplotype Relative Risk (HHRR) were calculated; 31 NTD fetuses and 62 adult controls were analysed for calculation of OR of homozygotic MTHFR.The results are as follow:Nuclear family analysis: OR=3.2( 95%CI=1.120~11.169);TDT(paired χ2)=5.762,P<0.05,HHRR(χ2)=6.727,P<0.05;homozygotic MTHFR of fetus vs adult control: OR=3.21,P<0.05. The 677th allele of MTHFR is abnormally transmitted in NTD nuclear families.Homozygotic MTHFR of the fetus may be a genetic factor of NTD in China.  相似文献
3.
父母MTHFR基因型对后代发生神经管畸形的影响   总被引:9,自引:1,他引:8       下载免费PDF全文
朱慧萍  李竹  刀京晶  赵欣荣  赵如冰 《遗传》2000,22(5):285-287
本研究旨在探讨父母双方MTHFR基因型与其后代发生神经管畸形风险性的关 系。采用成组匹配的病例对照研究方案,用纸片法采集病例和对照外周血标本,用PCR-RFLP方法确定基因型(C677T)。结果显示,分别比较两组父亲或母亲基因型频率时,差别不显著;将父母基因型联合起来分析则发现,病例组父母等位突变基因频率(T)高于对照组父母,提示后代是纯合突变( TT)概率越大,发生NTD的风险性也越大。结论是,父母双方的基因型对后代发生NTD的风险性有同等重要的作用,父母双方传递给胎儿的一对突变等位基因(T/T)是NTD发生的风险因素之一。 Abstract:The effect of parental MTHFR genotypes on fetal phenotype of NTD is studied.It was designed as group matched case-control study.Venous blood cases and controls were collected by dry blood spots.Genotype(C677T)of each sample was decided by PCR-RFLP method.When the genotypes of father and mother are compared separately,no significant difference is discovered between cases and controls.On the other hand,when the mutant allele frequency(T)is computed for father and mother together,it is significantly higher in cases than in controls.Higher probabilities of the offspring being homozygotes(TT),higher the risk for NTD occurrence has been observed.It is concluded that genotypes of MTHFR for both father and mother have the same impact on NTD occurrence of their offspring.It is the pair of mutant allele(T/T)which transmitted to the baby from its parents that increases the risk.  相似文献
4.
神经管畸形相关基因的研究进展   总被引:7,自引:1,他引:6       下载免费PDF全文
曲梅  李竹 《遗传》2002,24(6):695-698
神经管畸形是由遗传和环境因素共同作用而导致的一种常见的出生缺陷。遗传因素中包括细胞增殖因子、转录因子及影响叶酸代谢的关键酶的基因。本文着重从动物模型和群体流行病学调查两方面,简述目前研究的热点基因及特定位点的遗传多态性与神经管畸形的关系,从而揭示多因素作用在神经管畸形病因学研究中的意义。 Progress in Researches on Neural Tube Defects Related the Genes QU Mei,LI Zhu Institute of Reproductive and Child Health of Peking University,National Reference Laboratory on Reproductive Health Research Ministry of Health,Beijing 100083,China Abstract:Neural tube defects are common birth defects which are ascribed to the combination of genetic and environmental factors.The genetic factors include cell growth factors,transformation factors and key enzymic genes involved in folate metabolism.This paper reviews the genes as focus of current investigantion and the relationship between the genetic polymorphism on the specific sites and neural tube defects based on animal model and population epidemiological study.It indicats that the multifactors play an important role in the etiology of neural tube defects. Key words:neural tube defects; genetic polymorphism  相似文献
5.
为比较中国蒙汉两族人群MTHFR基因第677位核苷酸多态性的分布情况,获得该位点多态性的群体遗传学数据,本研究应用PCR扩增技术, 其扩增产物用限制性核酸内切酶Hinf I消化后进行非变性聚丙烯酰胺凝胶电泳,分析蒙汉族人群中MTHFR基因第677位核苷酸基因型(野生型、杂合型和突变纯合型)的分布频率。结果表明,蒙族人群基因型构成以野生型为主,占45.6%,突变杂合型占39.2%,突变纯合型仅占15.2%,汉族人群基因型构成以突变杂合型为主,占55.7%,野生型仅占17.9%,突变纯合型占26.4%,明显高于蒙族人群。经χ2检验,两组基因型构成比具有显著性差异(P<0.001);蒙族人群MTHFR 677T等位基因频率为34.8%,经u检验显著低于汉族人群(54.2%)的频率。据此认为,中国蒙族人群MTHFR热敏感性基因突变频率显著低于汉族人群,提示该基因多态性分布在中国不同民族人群中存在差异。 Abstract:The purpose of this study is to compare the genetic polymorphism distribution of the 677th nucleotide of MTHFR between the Mongolian population and the Hans of China,and to obtain the population genetic data of this polymorphism.Using PCR-RFLP method,the authors analyzed the genotypes of the 677th nucleotide of MTHFR in Mongolians and Hans.Results show that in Mongolian population,the proportion of wild type is 45.6%,proportion of heterozygotes is 39.2% and that of homozygotes is 15.2%; While in Hans,proportions are wild type 17.9%,heterozygotes 55.7% and homozygotes 26.4%.The ratios of genotypes are significantly different between Mongolian and Han populations(χ2-test,P<0.001).The 677th allele frequency in Mongolians is 34.8%,lower than that in Hans(54.2%,u-test,P<0.001).This suggests that the mutant MTHFR gene frequency is significantly higher in the Han population than in the Mongolian population in China.  相似文献
6.
中国柱角水虻亚科新种(双翅目:水虻科)   总被引:2,自引:0,他引:2  
7.
8.
北京国家体育场周边趋光性昆虫物种多样性及优势度分析   总被引:2,自引:0,他引:2  
李竹  袁峰  覃晓春  黄浩  常凌小 《昆虫知识》2007,44(3):423-427
2005年7月20日到8月15日通过灯光诱捕对北京国家体育场周边的趋光性昆虫做了物种多样性调查,分析了其优势度。结果表明:国家体育场周边的趋光性昆虫包含10目42科112种,以鞘翅目和鳞翅目数量最大;青革土蝽和黄鞘婪步甲为优势种;在8月6日优势种和所有昆虫的总体数量出现一个高峰。  相似文献
9.
记述新直脉蝎蛉科1新属1新种Neorthophlebopsis qishuiheensis gen.et sp.nov.,并以其Sc很长,Rs与M分支同一水平,Rs1 2分支在Pt之前,M与CuA汇合,臀区3支粗壮横脉,呈一字斜形排列等特征与已知属相区别.新属种系铜川昆虫组合的新成员,属陕西昆虫群.化石标本采自陕西铜川中三叠统铜川组下段上部灰绿色泥页岩.铜川组的时代相当欧洲拉丁尼期(Ladinian Stage).  相似文献
10.
裴丽君  李竹 《遗传》2004,26(2):239-243
神经管畸形和颅面畸形是最常见的出生缺陷,由遗传和环境因素共同作用所致,大规模的人群流行病学研究已证实,叶酸能降低发生这类畸形的危险。叶酸缺乏是神经管和颅面畸形发生的主要环境因素,但其机制尚不清楚,通过对与叶酸代谢有关的还原叶酸载体(reduced folate carrier,RFC)的生化特点、生理功能、还原叶酸载体基因(RFC1)结构功能、调控、表达及其与叶酸水平和神经管颅面畸形的关系等研究进展进行综述,从而为神经管和颅面畸形的病因学研究提出可能的候选基因。 Abstract: Neural tube and craniofacial defects are common birth defects which are ascribed to the combination of genetic and environmental factors. The population epidemiological studies suggested that periconceptional use of multivitamins containing folic acid can reduce a woman’s risk of having a child with neural tube and craniofacial defects. It’s a major environmental factor that periconceptinal women with deficiency of folic acid may increase their risk for delivering babies with neural tube and craniofacial defects, but the mechanism by which folic acid facilitated this risk rediction is unknown. This paper reviews folate transport carrier, Reduced Folate Carrier(RFC)’s characteristics in biological chemistry, physiological function, the folate transport mechanism, structure, function, regulation and expression of reduced folate carrier gene(RFC1), and the relationship between RFC1 with plasm or erythrocyte folate level and neural tube defects, et al. It is suggested a etiologic hypothesis in investigation of candidate gene encoding specific folat-related pathways of neural tube and craniofacial defects.  相似文献
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