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31.
S. C. Mitchell R. H. Waring D. Land W. V. Thorpe 《Cellular and molecular life sciences : CMLS》1987,43(4):382-383
Summary The production of odorous urine after the ingestion of asparagus has been shown to occur in 43% of 800 volunteers investigated. This characteristics is reproducible over a 12-month-period and has been shown to remain with individuals for virtually a lifetime. Family studies suggest that the ability to produce the odorous urine is inherited as an autosomal dominant trait. 相似文献
32.
The study of candidate genes over the past three decades has yielded notable successes in common-disease genetics. During
this time, however, interpretation of genetic association studies has been hampered by the use of clinical cohorts of inadequate
power and insufficient information on genetic variation in candidate genes. The unavailability of highthroughput and low-cost
genotyping technologies has also limited the scope of complex-disease genetic studies. More recently, however, the sequencing
and characterization of variation within the human genome has revolutionized genetic studies and enabled full genome-wide
scans for genes associated with disease. The identification of disease-associated (causative) genes has illuminated disease
mechanisms. The translation of this knowledge into direct clinical benefit in diagnosis, prognosis and therapy for an individual’s
disease still remains a challenge.
Received 11 September 2006; received after revision 17 December 2006; accepted 18 January 2007 相似文献
33.
测定成都麻羊和四川肉用黑山羊地方品种羔羊哺乳期母羊的产乳量、乳常规营养成分、乳蛋白组分和乳酪蛋白遗传多态性.结果表明,母羊哺乳期的产乳量(kg)成都麻羊、金堂黑山羊、乐至黑山羊、自贡黑山羊和建昌黑山羊相应分别为46.15±1.78,101.67±4.93,85.76±3.36,54.32±6.64和36.65±2.65,成都麻羊极显著低于金堂黑山羊、乐至黑山羊(P<0.01),而极显著高于建昌黑山羊P<0.01)与自贡黑山羊差异不显著(P>0.05);乳中常规营养成分含量(g/L)均较高,范围乳脂为58.59~60.52、乳蛋白为44.18~46.37和乳糖为44.00~47.30;经产母羊常乳主要蛋白组分的相对含量(%)范围α-La为5.35~5.80,β-Lg为14.46~15.18,CN为70.04~71.01,IgG为7.04~7.31,SA为2.02~2.15,品种间差异不显著(P>0.05);酪蛋白电泳染色显示出α-CN和β-CN图带,α-CN均呈现4种不同的带型αS1-CN(H),αS1-CN(L)、αS2-CN(CC)型和αS2CN(CD),其中均以αS2-CN(CD)占优势.β-CN呈现单态,带型为β-CN(AB). 相似文献
34.
Characterization, development and exploitation of EST-derived microsatellites in Gossypium raimondii Ulbrich 总被引:7,自引:2,他引:7
WANG Changbiao GUO Wangzhen CAI Caiping ZHANG Tianzhen 《科学通报(英文版)》2006,51(5):557-561
COTTON IS AN IMPORTANT GLOBAL CASH CROP. IN THE RECENTYEARS, MOLECULAR MARKER TECHNOLOGY HAS BEEN WIDELY APPLIED TO SUCH STUDIES ON COTTON AS GENETIC MAP- PING[1―4], VARIETY PURITY DETECTION[5], GENETIC DIVERSITY ANALYSIS[6], MOLECULAR MARKER-ASSISTED BR… 相似文献
35.
研究西安市汉族人群中2型糖尿病患者IRS-2基因密码子1057g/a多态性与运动易感性间的相关性.PCR—RFLP的方法检测IRS-2基因密码子1057g/a多态性后,随机分3组:gg、ga和aa基因型组,经12周的太极拳运动锻炼后发现,aa基因型组对运动的易感性最高,反映糖尿病情改善的主要指标均发生了良好的改变.发现西安市汉族人群中不同2型糖尿病患者IRS-2基因型对运动的易感性存在着明显差异,aa基因型组患者的运动易感性高于其他基因型. 相似文献
36.
Scanning for sisnatures of geosraphically restricted selection based on population genomics analysis 总被引:1,自引:0,他引:1
DENG LiBin TANG XiaoLi KANG Jian WANG QingYun ZENG ChangQing 《科学通报(英文版)》2007,52(19):2649-2656
Natural selection, as the driving force of human evolution, has direct impact on population differentiation. However, it is still unclear to what extent the genetic differentiation has been caused by natural selection. To explore this question, we performed a genome-wide scan with single nucleotide polymorphism (SNP) data from the International HapMap Project. Single locus FsTanalysis was applied to assess the frequency difference among populations in autosomes. Based on the empirical distribution of FsT, we identified 12669 SNPs correlating to population differentiation and 1853 candidate genes subjected to geographic restricted natural selection. Further interpretation of gene ontogeny revealed 121 categories of biological process with the enrichments of candidate genes. Our results suggest that natural selection may play an important role in human population differentiation. In addition, our analysis provides new clues as well as research methods for our understanding of population differentiation and natural selection. 相似文献
37.
采用mtDNA多态性标记对成都麻羊与四川各地黑山羊品种(群体)D-loop序列多态性进行分析.结果表明,供试山羊品种(群体)mtDNA片段长度为16kb左右,mtDNA D-loop片段长度为1210~1212bp,共检测到10种单倍型,群体间共有多态座位83个,单一多态座位23个,简约信息座位24个,平均核苷酸歧异度为0.001510,D-loop序列多态性较贫乏.经聚类,成都麻羊与四川各地黑山羊品种(群体)分为两大类,成都麻羊首先与金堂黑山羊(D=0.203)聚在一起后,再依次与乐至黑山羊(D=0.223)、建昌黑山羊(D=0.477)、白玉黑山羊(D=0.593)形成一大类;合江黑山羊与江安黑山羊(D=0.231)先聚在一起后,再与自贡黑山羊(D=0.337)聚为1类,营山黑山羊与嘉陵黑山羊(D=0.242)聚为1类,2类形成另一大类.最后两个大类聚在一起.聚类结果与供试山羊品种(群体)来源和生态地理分布相一致. 相似文献
38.
为了解生长激素受体(GHR)基因多态性在江苏汉族人群中的分布,通过多重PCR及PCR-RFLP的方法对269例江苏地区正常汉族人进行GHR基因3个位点的多态性分析,并与文献中报道的其它种族和地区的人群进行比较分析.结果显示江苏地区汉族正常人群中GHR基因型以fl/fl、I/L、P/P发生频率最高,这种分布在男女之间没有差异,与其它地区汉族人比较没有明显差异,与日本人差异也不明显,而与法国、俄罗斯人差异明显.研究表明,GHR基因3个位点多态性在不同种族之间分布存在着明显的差异,这种差异有可能是导致不同种族间人体测量学差异及对一些疾病的易感性及对药物的反应性不同的因素之一. 相似文献
39.
The pedigrees of three sequenced rice cultivars were analyzed to show that a majority of the genetic composition of 'Nipponbare' originates from japonica cultivars while the minority originates from indica cultivars. In contrast, '93-11' is derived mainly from indica cultivars with a smaller contribution from japonica cultivars. All ancestors of 'Guang lu ai 4' appeared to be indica lines. A set of molecular markers (46 InDels and 53 SSRs) polymorphic between 'Nipponbare' and '93-11' were examined in 46 typical indica and 47 typical japonica cultivars selected from 443 accessions according to Cheng's index. All cultivars were divided into indica and japonica groups without overlapping when clustered by Cheng's index, InDels and SSRs. Much higher InDel and SSR diversity between groups than within groups implies that the marker polymorphisms between 'Nipponbare' and '93-11' represent a large proportion of inter-subspecific diversity. About 85% of indica cultivars and more than 90% of japonica cultivars were confirmed to have the same PCR banding patterns as '93-11' and 'Nipponbare', respectively. Some polymorphic loci between 'Nipponbare' and '93-11' cannot be validated in other indica and japonica cultivars, either as subspecies-specific but not predominant alleles, or alleles not specific between the two groups. It was concluded that molecular markers developed from sequence polymorphism between 'Nipponbare' and '93-11' often represent inter-subspecific diversity, although some exceptions were sensitive to either particular marker loci or particular cultivars. 相似文献
40.
近年来,在计算机软件业,面向对象的程序设计的思想已经被越来越多的设计人员所接受.面向对象的编程(OOP)和数据抽象已经成为最常用的编程术语.本文以C 为例,讨论OOP的编程风格与特性. 相似文献