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991.
大熊猫电刺激采精及精液冷冻保存研究 总被引:6,自引:1,他引:5
对卧龙自然保护区大熊猫研究中心的9只5.5-16.5岁的雄性大熊猫进行了17次电刺激采精,其中3只是能进行自然交配并繁殖了后代的种公兽,比较研究了精液离心、不同稀释液和冷冻方法对大熊猫精液超低温冷冻保存后的活力、运动状态、精子和顶体形态的影响。细冷冻是1种较好的超低温冷冻精液的方法。 相似文献
992.
近年来我国系统工程理论与实践的研究及进展——《系统工程理论与实践》1995~1998年论文及其作者和引文的统计分析与评价 总被引:7,自引:2,他引:5
黄立军 《系统工程理论与实践》2001,21(3):1-7
对《系统工程理论与实践》1 995年至 1 998年刊载的论文及其作者和引文进行了统计分析 ,揭示了近年来我国系统工程理论与实践的研究水平 .文章探讨了作者的地区分布和系统分布的特点 ,确定了系统工程领域多产作者及多产单位的数量和比例 ,并研究了引文数量、比例、语种、文献类型及年代. 相似文献
993.
Kooner JS Saleheen D Sim X Sehmi J Zhang W Frossard P Been LF Chia KS Dimas AS Hassanali N Jafar T Jowett JB Li X Radha V Rees SD Takeuchi F Young R Aung T Basit A Chidambaram M Das D Grundberg E Hedman AK Hydrie ZI Islam M Khor CC Kowlessur S Kristensen MM Liju S Lim WY Matthews DR Liu J Morris AP Nica AC Pinidiyapathirage JM Prokopenko I Rasheed A Samuel M Shah N Shera AS Small KS Suo C Wickremasinghe AR Wong TY Yang M Zhang F;DIAGRAM;MuTHER Abecasis GR Barnett AH Caulfield M Deloukas P 《Nature genetics》2011,43(10):984-989
We carried out a genome-wide association study of type-2 diabetes (T2D) in individuals of South Asian ancestry. Our discovery set included 5,561 individuals with T2D (cases) and 14,458 controls drawn from studies in London, Pakistan and Singapore. We identified 20 independent SNPs associated with T2D at P < 10(-4) for testing in a replication sample of 13,170 cases and 25,398 controls, also all of South Asian ancestry. In the combined analysis, we identified common genetic variants at six loci (GRB14, ST6GAL1, VPS26A, HMG20A, AP3S2 and HNF4A) newly associated with T2D (P = 4.1 × 10(-8) to P = 1.9 × 10(-11)). SNPs at GRB14 were also associated with insulin sensitivity (P = 5.0 × 10(-4)), and SNPs at ST6GAL1 and HNF4A were also associated with pancreatic beta-cell function (P = 0.02 and P = 0.001, respectively). Our findings provide additional insight into mechanisms underlying T2D and show the potential for new discovery from genetic association studies in South Asians, a population with increased susceptibility to T2D. 相似文献
994.
Genetic variation near IRS1 associates with reduced adiposity and an impaired metabolic profile 总被引:1,自引:0,他引:1
Kilpeläinen TO Zillikens MC Stančákova A Finucane FM Ried JS Langenberg C Zhang W Beckmann JS Luan J Vandenput L Styrkarsdottir U Zhou Y Smith AV Zhao JH Amin N Vedantam S Shin SY Haritunians T Fu M Feitosa MF Kumari M Halldorsson BV Tikkanen E Mangino M Hayward C Song C Arnold AM Aulchenko YS Oostra BA Campbell H Cupples LA Davis KE Döring A Eiriksdottir G Estrada K Fernández-Real JM Garcia M Gieger C Glazer NL Guiducci C Hofman A Humphries SE Isomaa B Jacobs LC Jula A Karasik D Karlsson MK 《Nature genetics》2011,43(8):753-760
Genome-wide association studies have identified 32 loci influencing body mass index, but this measure does not distinguish lean from fat mass. To identify adiposity loci, we meta-analyzed associations between ~2.5 million SNPs and body fat percentage from 36,626 individuals and followed up the 14 most significant (P < 10(-6)) independent loci in 39,576 individuals. We confirmed a previously established adiposity locus in FTO (P = 3 × 10(-26)) and identified two new loci associated with body fat percentage, one near IRS1 (P = 4 × 10(-11)) and one near SPRY2 (P = 3 × 10(-8)). Both loci contain genes with potential links to adipocyte physiology. Notably, the body-fat-decreasing allele near IRS1 is associated with decreased IRS1 expression and with an impaired metabolic profile, including an increased visceral to subcutaneous fat ratio, insulin resistance, dyslipidemia, risk of diabetes and coronary artery disease and decreased adiponectin levels. Our findings provide new insights into adiposity and insulin resistance. 相似文献
995.
996.
In this paper, a new method for mobile robot map building based on grey system theory is presented, by which interpretation and integration of sonar readings can be solved robustly and efficiently. The conception of "grey number" is introduced to model and handle the uncertainty of sonar reading. A new data fusion approach based on grey system theory is proposed to construct environment model. Map building experiments are performed both on a platform of simulation 相似文献
997.
在一个地铁公交与道路驾车两种出行方式并存且竞争的交通系统中,出行者按照时间价值、早到与晚到惩罚的差异被分成两组,地铁可以按边际成本或者平均成本确定票价,道路可以不收通行费或者以道路系统最优化原则收费.我们研究不同收费策略组合下的交通方式选择问题,并利用算例分析了出行需求及其构成对交通方式选择和个人出行成本的影响. 相似文献
998.
Mauremys mutica (Cantor, 1842) is an endangered species in China. Main phenotypic variations in body color, body weight, body shape, clutch size, egg size, and hatchling size were revealed between the southern and northern populations. Both populations have the phenomenon of "larger male" sexual size dimorphism (SSD), especially in the southern population. Furthermore, genetic variations between the two populations were analyzed by RAPD band patterns of 30 random individuals in each population. The average genetic distance was 0.299±0.108 among the samples of two populations. The average genetic distance between southern and northern populations was 0.305±0.046. Cluster analysis indicated that all the individuals from the southern and northern populations were clustered among themselves to form two distinct clades. A total of 20 population-specific RAPD fragments were scored from 16 primers, and could be used as RAPD markers for distinguishing the southern and the northern population. Based on the nucleotide sequences of two RAPD markers, two pairs of SCAR primers (SC1-S and SC2-S) were designed, which could be used as SCAR markers for the southern population. According to the significant phenotypic and genetic variations, we suggested that the northern population and southern population might be considered as two separate taxa, the "northern taxon" and the "southern taxon", and the conservation should be respectively conducted on the two taxa. 相似文献
999.
运动发酵单胞菌(Zymomonas.mobilis)是目前发现的乙醇发酵能力最强的微生物之一,被认为是进行大规模乙醇生产的潜在菌种;但由于其可利用的碳源范围窄,所以对其进行基因工程改造首先需要有较好的载体系统.以Z.mobilis内源质粒pZM2和大肠杆菌(E.coli)质粒pBR328、pACYC184为出发质粒,构建了三个Z.mobilis-E.coli之间的克隆型穿梭质粒,即pZB1、pZB21和pZB31.对它们在Z.mobilis CP4中的稳定性、拷贝数的初步比较分析表明:pZB21最稳定、拷贝数最高,pZB31次之,pZB1最差.进一步以pZB21为载体,在Z.mo- bilis CP4中表达E.coli的talB基因,酶活水平为0.087 U/mg蛋白.证明pZB21是能用于基因表达的、较为理想的Z.moblis-E.coli之间的穿梭载体. 相似文献
1000.
内蒙古交通运输货运量及货运周期转量的预测 总被引:1,自引:0,他引:1
应用系统工程理论,用定性和定量相结合的方法,建立了内蒙古自治区交通运输货运量和货运周转量的预测模型,对货运量和货运周转量进行经济分析和讨论,预测其发展趋势并进行了前景分析。 相似文献