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31.
<正>As one of the most deadly diseases,the outbreak of Ebola virus disease(EVD)is causing panic in West Africa and posing alarms globally.Since the re-emergence of EVD,China authority has been consistently providing support for Africa in its fight against Ebola.On September 16,2014,a laboratory testing team and a medical team,consisting of 59public health experts and medical staffers,were dispatched to assist local hospitals in West African countries to set up lab screening and clinical treatment of EVD(http://www.taiwan.cn/xwzx/Technology/201409/t20140917_7354545.  相似文献   
32.
73例中国人血友病甲基因突变的分析   总被引:5,自引:1,他引:5  
我们用Southern blotting、PCR、变性梯度凝胶电泳(DGGE)和DNA测序等方法对73例血友病甲患者(经上海瑞金医院测定血浆FVⅢ:C和vWF:Ag诊断,其中无亲缘关系患者65例,按FVⅢ:C水平分为轻、中、重三型。FVⅢ:C< 2%为重型,共47例;FVⅢ:C 2%-5%为中型,共9例;FVⅢ:C5%-25%为轻型,共1 7例)进行FVⅢ基因突变检测。共检出内含子22倒位23例,均为重型,约占重型的49%,与国外报道相似。余下50例(其中无亲缘关系者45)用PCR-DGG E分析所有外显子及其侧翼内含子序列,发现异常条带则进行DNA测序。在17例患者中检出突变13种,其中无义突变5种,均为重型;错义突变6种,除1例外都是轻中型;小缺失2例,都是重型;其中,AA466Lys(AAG)-Thr(ACG)、719Tyr(TAC)-Stop(TAG)、AA826 Asp(GAC)-Glu(GAA)、312Ile(ATC)-xxC及AA1551-1552del(AGAA)为新发现的突变。有亲缘关系的患者都有相同的基因突变,而在无亲缘关系患者未发现相同突变。基因突变与临床表现基本相符。 Abstract:We use Southern blotting,PCR,denaturing gradient gel electrophoresis(DGGE)and DNA sequencing to detect gene mutations of haemophilia A in Chinese population.73 cases(47 severe)(FVIII:C<2%),9 moderate(FVIII:C 2%~5%),17 mild(FVIII:C 5%~25%)of haemophilia A were first screened with Southern blotting,23 were found to be the intron 22 inversion type,all being severe cases.The remaining 50 cases without intron 22 in version were examined with PCR-DGGE.Genomic DNA were amplified using GC-clamped primers covering all the exons and all flanking intron regions.Abnormal bands were sequenced.13 different mutations were identified,including 5 nonsense mutations,6 missense mutations and 2 small deletions.5 mutations,AA466Lys(AAG)-Thr(ACG),AA719Tyr(TAC)-Stop(TAG),AA826Asp(GAC)-Glu(GAA),AA312Ile(ATC)-xxC and AA1551-1552del(AGAA)have not been reported before.Generally the genetic defects correspond to the clinical conditions.  相似文献   
33.
<正>Dear Editor,Shortly after initiating thePhysical Anthropological Research on Han Chineseresearch project,we applied uniform sampling methods as well as methods and instruments of measurement to obtain a complete set of measurements of physical anthropological indicators among Han populations across China.Among these measurements,body stature was a key indicator.Currently,there should be reliable  相似文献   
34.
陆地棉枯萎病抗性基因的等位性测定及连锁分析   总被引:5,自引:0,他引:5  
1995-1996年,对我国育成的有代表性的5个抗病品种进行抗枯萎病基因的等位性测定。结果表明:在所选用的5个抗病品种中至少存在两个不同的抗病基因(暂定名为Fwl和Fw2)。连锁分析显示:Fwl与T586的8个标志性状间、Fw2与T582、T586的13个标志性状间无连锁关系。 Abstract:Allelism in vestigation of genes resistante to Fusarium wilt in cotton suggested that there were 2 genes(assigned symbols Fw1 and Fw2)in 5 cultivars used.No linkage was found between Fw1 and the marker genes in T586 and between Fw2 and those marker genes in T582 and T586.  相似文献   
35.
小鼠基因组研究进展李善如1,2王冬平1陈永福2(1.军事医学科学院实验动物中心,北京100071)(2.中国农业大学生物学院,北京100094)TheDevelopmentofMouseGenomeResearchLIShanru1,2WANGDon...  相似文献   
36.
Breeding high-yielding and nutrient-efficient cultivars is one strategy to simultaneously resolve the problems of food security,resource shortage,and environmental pollution.However,the potential increased yield and reduction in fertilizer input achievable by using high-yielding and nutrient-efficient cultivars is unclear.In the present study,we evaluated the yield and nitrogen use efficiency(NUE) of 40 commercial maize hybrids at five locations in North and Northeast China in 2008 and 2009.The effect of interaction between genotype and nitrogen(N) input on maize yield was significant when the yield reduction under low-N treatment was 25%-60%.Based on the average yields achieved with high or low N application,the tested cultivars were classified into four types based on their NUE:efficient-efficient(EE) were efficient under both low and high N inputs,high-N efficient(HNE) under only high N input,low-N efficient(LNE) under only low N input,and nonefficient-nonefficient under neither low nor high N inputs.Under high N application,EE and HNE cultivars could potentially increase maize yield by 8%-10% and reduce N input by 16%-21%.Under low N application,LNE cultivars could potentially increase maize yield by 12%.We concluded that breeding for N-efficient cultivars is a feasible strategy to increase maize yield and/or reduce N input.  相似文献   
37.
本文根据系统学原理,提出了建立新类元的依据;并据此从分类和系统发育上论证了近金线属AnchicyclocheilusLietLan独立成属的可能性,认为应将近金线属归于金线属;修订了金线属SinocyclocheilusFang的鉴别特征。  相似文献   
38.
INTRODUCTIONTelomerase is a ribonucleoprotein complex that plays a critical role in telomeremaintenance and cellular immortality. Telomerase has been considered as tumordiagnostic marker and potential target for cancer therapyll, 2]. A sensitive, reliableand quantitative assay is of high interest in this field. The development of a very sensitive Telomeric Repeat Amplification Protocol (TRAP) for measuring telomerajseactivity in cell extracts has been proved to be an important tool for…  相似文献   
39.
人类指掌皮肤嵴纹与智力发育的相关性研究   总被引:5,自引:1,他引:5  
本工作对120例遗传型智残者和60例非遗传型智残者的指、掌皮肤嵴纹数进行分析,并分别与相同例数的对照组同类资料进行比较,找出与智力发育相关的指端、指间区、指基部皮纹参数,据此将遗传型智残组按智商值的不同分为6个组,将不同智商组对应的各区嵴纹数进行分析处理。结果表明,指端皮肤嵴纹数与智商呈正相关,相关系数r=0.8319,各指间区和指基部嵴纹数与智商值呈负相关,相关系数r=-0.7392。 Abstract Digital and palmar of 120 cases of hereditary mental deficiency and 60 cases of non-hereditary mental deficiency were analysed, and compared with the control group using the same cases and identical data, and then skin vein parameter interrelated with intelligence development for digital end, interdigital area, digital root were found. In the light of this we divided the hereditary mental deficiency group into 6 accorcding to IQ value, and analysed statistically every area ridge count corresponding to different IQ group. The result showed that ridge count of digital end was positively correlated with IQ value correlative coefficientr=0.8319; Whereas ridge count of interdigital area and digital root were negatively correlated with IQ value correlative cofficientr=0.7392.  相似文献   
40.
染色体倍数与杂种优势之关系初探   总被引:2,自引:0,他引:2  
杂种优势是植物界的一个普遍现象,也是提高栽培作物产量的一个十分重要的途径。目前,除少数栽培作物外,大部分作物都已成功地利用了杂种优势。杂种优势的利用基本上集中在二倍体,在生产上大面积利用的以收获种子为目的的多倍体并不多,如小麦(异源六倍体)、大豆(异源四倍体)、花生(异源四倍体)等。其原因除制种较困难外,关键是杂种优势多不及二倍体,但到目前为止,尚未有一个完整的理论对此进行系统解释,本文将就这一问题进行讨论,以供同行参考。1 内源优势与外源优势笔者认为,多倍体作物杂种优势不强与其染色体组成有关。…  相似文献   
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