血清饥饿、汇合培养及放线菌酮对奶牛成纤维细胞周期的影响

在动物克隆研究中,研究者普遍认为位于细胞周期的G0+G1期的二倍体细胞对于核移植中供核细胞的重新程序化是必需的。本文探讨了血清饥饿、汇合培养及放线菌酮（CHX）处理对不同传代次数的体外培养奶牛成纤维细胞周期分布的影响。流式细胞仪分析结果显示：第3代和第13代细胞经血清饥饿处理72h后,细胞周期分布与对照差异显著(P<0.05);汇合培养可以显著增加奶牛成纤维细胞处于G0+G1期细胞数。CHX处理第3代细胞经CHX处理后处于G0+G1期的细胞数差异不显著,而第13代细胞处理后差异显著。结果表明体外培养奶牛成纤维细胞高代对血清饥饿、汇合培养及CHX处理更敏感。     

禽流感发生后青海湖水鸟的种群现状

于2006年和2007年4~9月,在青海湖对水鸟的资源状况进行了调查。结果表明,青海湖地区迁徙水鸟的多样性呈季节性变化。春季迁徙期水鸟多样性较高,水鸟的种类和数量都较为丰富;进入繁殖期以后,各地点的水鸟多样性趋于下降;随着秋季迁徙期的来临,水鸟多样性又再度升高,水鸟的种类和数量接近或超过春季迁徙期。在春季迁徙期,布哈河口、铁卜恰河口、泉湾和尕日拉的斑头雁(Anser indicus)、棕头鸥(Larus brunnicephalus)、渔鸥(L.ichthyaetus)、普通鸬鹚(Phalacro coraxcarbo)和赤麻鸭(Tadorna ferruginea)5种水鸟的数量都较多,致使种间相遇几率也较高;进入繁殖期以后,尕日拉的种间相遇率降低,而蛋岛和黑马河的种间相遇率有所增加,其余如布哈河口、铁卜恰河口和泉湾仍维持较高的水平;秋季迁徙期5种水鸟大多以集群的方式进行活动,主要集中在少数几个地点,如布哈河口、泉湾和黑马河,因此这三处的种间相遇率随之增加。最后,有针对性地提出了禽流感监测和保护管理建议。     

MSM and HIV/AIDS in China

This article profiles current status of spread and control of HIV/AIDS in China. China has a significant population of MSM (men who have sex with men) and they have been becoming very much alive in many ways since 1990s due to recent social changes. Some surveys indicate that great many of MSM are engaged in high-risk behaviors. In addition,majority of MSM have also experienced sexual encounters with women sometimes in their lives, which possibly contribute to spread of HIV to women. Some reports documented that HIV is becoming rampant among MSM since more than 1% of them are now infected. Political, cultural and custom elements could hinder intervention activities against HIV spread among MSM. Fortunately, many cities in China have seen that MSM were in cooperation with responsible institutions carrying out certain intervention measures. The general situation is promising. The authors forecast that the fast HIV spread among MSM of China could possibly be halted within several years when the authorities become more sensible to this issue, health service institutions offer unswerving efforts toward the MSM community and those who involve in MSM undertakes necessary responsibilities.     

利用大肠杆菌高效表达人载脂蛋白AI及其性质分析

载脂蛋白AI(apolipoproteinAI,apoAI)是高密度脂蛋白HDL的主要组成成分 ,流行病学研究表明apoAI的含量决定血浆中HDL的高低 ,而HDL具有胆固醇逆向转运的功能 ,起到降低冠心病发生概率的作用。通过大肠杆菌表达系统来生产apoAI的蛋白原proapoAI,蛋白的表达形式为包涵体 ,通过疏水柱进行柱上复性。同时在proapoAI和apoAI之间设计一个酸水解位点 ,通过将蛋白原proapoAI进行酸水解来得到成熟蛋白apoAI。最终得到的成熟蛋白apoAI在结构分析和脂结合特性上都与天然的apoAI相似 ,从而为该蛋白的工业生产上提供了一个良好的基础。     

用4个微卫星标记分析7个绵羊群体之间的遗传关系

分析了4个微卫星基因座BM143、OarHH35、OarAE101、BMS2508在7个绵羊群体（小尾寒羊、湖羊、乌珠穆沁羊、萨福克羊、多赛特羊、夏洛来羊、多赛特公羊×小尾寒羊母羊F1代杂种羊）286只绵羊中的遗传多态性。结果表明,这4个微卫星标记在7个绵羊群体中的等位基因数分别为9、11、14和9,其多态信息含量/有效等位基因数/杂合度分别为0.7073/3.7231/0.7314、0.8267/6.4399/0.8447、0.5743/2.5178/0.6028、0.6172/3.0712/0.6744,其中OarHH35的遗传变异最大,OarAE101最小。7个绵羊群体中小尾寒羊的遗传变异最大,湖羊的最小。基于Nei氏DA距离和DS标准遗传距离,采用UPGMA方法构建了系统发生树。该发生树将中国地方品种（小尾寒羊、乌珠穆沁羊、湖羊）和法国的夏洛来羊归为一类,将F1杂种羊、英国品种（萨福克羊和多赛特羊）归为另一类。绵羊微卫星基因分型技术为检查品种（群体）之间的遗传关系提供了一个有用的工具。 Abstract：The genetic polymorphisms of four microsatellite loci BM143,OarHH35,OarAE101,and BMS2508 were analyzed in 286 sheep of seven sheep populations (Small Tail Han sheep, Hu sheep, Ujumqin sheep, Suffolk sheep, Dorset sheep, Charolais sheep, F1 of Dorset♂ × Small Tail Han sheep♀). The numbers of alleles for BM143,OarHH35,OarAE101,and BMS2508 are 9, 11, 14 and 9 in seven sheep populations, respectively. The polymorphism information content/number of effective alleles/ heterozygosity of BM143,OarHH35,OarAE101 and BMS2508 were 0.7073/3.7231/0.7314, 0.8267/6.4399/0.8447,0.5743/2.5178/0.6028,0.6172/3.0712/0.6744 in 286 sheep, respectively. The results revealed the greatest genetic variation at OarHH35 locus and the lowest at OarAE101, the greatest genetic variation in Small Tail Han sheep and the lowest in Hu sheep among seven sheep populations. In the unweighted pair group method with arithmetic mean (UPGMA) dendrograms based on Nei's DA distance and Nei's DS standard genetic distance, the Chinese native breeds (Small Tail Han sheep, Ujumqin sheep, Hu sheep) were grouped together, then with Charolais sheep. The F1 crossbred sheep, and the two British native sheep (Suffolk sheep, Dorset sheep) also clustered together. Microsatellite genotyping in sheep provided a useful tool for examining the genetic relationships among breeds(populations).     

Paternal inheritance of mitochondrial DNA in the sheep (Ovine aries)

Paternal inheritance of mitochondria DNA in sheep was discovered by examination of 152 sheep from 38 hybrid families for mtDNA D-loop polymorphisms using PCR-RFLP, amplification of repeated sequence somain, and PCR-SSCP of the D-loop 5' end region of a 253 bp fragment. Our findings have provided the first evidence of paternal inheritance of mtDNA in sheep and possible mechanisms of paternal inheritance were discussed.     

利用流式细胞术研究大肠埃希菌对肝癌腹水瘤细胞系Hca—F25／CL—16A3的作用

利用小鼠肝癌腹水瘤细胞Hca-F25/CL-16A3,运用流式细胞技术研究了大肠埃希菌对肿瘤细胞的作用,对细胞DNA含量的影响以及诱导细胞凋亡的作用,结果表明：大肠埃希菌在直接希伤肿瘤细胞的同时,还可以影响细胞DNA的含量,并可诱导细胞发生调亡。     

江苏盐城黑紫鸥（Larus saundersi）繁殖微生境的选择

1999～2001年春夏对江苏盐城国家级自然保护区黑嘴鸥的繁殖微生境进行了调查,黑嘴鸥的繁殖生境包括碱蓬群落（Suaeda glauca）、獐毛群落（Aeluropus littoralis）和大米草群落（Spartina anglica）,通过生境可获得性与可利用性分析,得知黑嘴鸥营巢对碱蓬生境具有正选择性,对獐毛和大米草生境具有负选择性。对繁殖微生境选择研究的结果表明,黑嘴鸥繁殖微生境具有以下特征：植被高度5～25cm,植被盖度20%～60%,底栖生物量大于300g/m^2,距水源距离500～1000m,距人类活动干扰距离大于500m,滩涂开发和人为活动是影响盐城地区黑嘴鸥繁殖微生境选择的重要因素。本文对黑嘴鸥繁殖栖息地的保护和管理提出了一些建议。     

巴西蘑菇原种培养基的筛选

以麦草、稻草、棉籽壳、玉米秸、木屑、麦粒、玉米粒和麦麸为原料 ,从 2 0种培养基中筛选出 2种适合巴西蘑菇菌丝生长的原种培养基。用这 2种培养基生产的菌种 ,菌丝粗壮、洁白、浓密 ,萌发快。     

塔里木河流域荒漠河岸林群落的多元分析与环境解释

应用无偏对应分析（DCA）及二歧指示种分析（TWINSPAN）对塔里木河流域荒漠河岸林33个植物群落方资料进行了多元分析－排序和数量分类,并应用植物群落的排序值与环境参数的多元回归分析给出各群落类型的定量环境解释,探讨了该区植物群落的基本类型,生态梯度及其与环境因子的定量关系,结果表明,塔里木河流域漠河岸林的群落类型及其分布主要取决于土壤湿度和盐分含量,并可通过环境参数的数字表达式定量的确定。