共查询到19条相似文献,搜索用时 62 毫秒
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我国幅员辽阔,生物类型多种多样,是世界上拥有鸟类种类最多的国家之一。截至1999年底,已知有鸟类1253种948亚种,隶属于21目83科,其中有多种为我国特有或珍稀濒危的鸟类。近年来由于环境污染、植被破坏及非法捕猎等种种原因,许多鸟类尤其是珍稀鸟类正逐步濒临灭绝。为了加紧保护野生鸟类种群,我们对珍稀鸟类采用了人工饲养、交配等手段以提高繁殖率,并已经在部分鸟类中获得成功。但是,在全世界的鸟类中有50%是单态性鸟。他们的性别不论是在幼鸟还是在成鸟时期,都很难 相似文献
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鸟类性别鉴定曾经通过外科手术对生殖腺直接进行检测,此法不仅繁琐而且有时会导致鸟的不育;细胞学水平上鉴定性别是通过直接观察W、Z性染色体而进行,但由于染色体数目大、分散难度高,很容易引起人为的主观因素导致结果错误。近年来利用鸟类W染色体上的性连锁基因或DNA序列,通过PCR、原位杂交等技术建立起来的.DNA分子水平性别鉴定方法,发展迅猛,准确度高,操作简便。此技术一旦形成体系,对鸟类研究、濒危物种保存等都将具有非常重要的意义。 相似文献
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鸟类的性别决定是一个多基因参与的级联调控过程。这一过程受Z染色体连锁的DMRT1基因, W染色体连锁的PKC1W和其它多种因子共同调控。本文综述了性别决定基因及其功能、性别鉴定方法等方面的研究进展。Abstract: Avian sex determination is a multiple gene regulation cascade. Genes such as the Z chromosome-linked DMRT1 gene, W chromosome-linked PKCIW gene and other factors have been demonstrated to be involved in this process. In this paper, we review the recent progress in this field. The investigation of functions of sex determinate genes and methods of sexing birds are discussed here. 相似文献
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目的:研究人类肿瘤相关基因CHD5基因miR-shRNA慢病毒对结直肠癌Lovo细胞的影响。方法:利用软件设计对CHD5基因干扰有效的序列,合成靶序列,退火形成双链DNA,酶切后与载体相连接。将重组慢病毒载体pPRIME-TET-GFP-CHD5与慢病毒包装质粒pCMV-VSV-G,pRSV-Rev,pMDLg-pRRE共转染293FT细胞,将包装重组慢病毒感染人类结直肠癌Lovo细胞。通过荧光定量PCR和Western blot验证CHD5基因在细胞中的表达情况,应用MTT检测CHD5低表达对Lovo细胞增殖的影响。结果:成功构建pPRIME-TET-GFP-CHD5重组质粒,经酶切及序列测定正确,包装的病毒滴度为3.1×106TU/ml。用制备的病毒上清感染Lovo细胞后,荧光定量PCR和Western blot分析结果显示该慢病毒可分别在转录和蛋白质水平上抑制Lovo细胞CHD5基因的表达,并使得Lovo细胞增殖失控。结论:成功构建CHD5慢病毒表达载体,表达的慢病毒可有效的感染Lovo细胞,提高Lovo细胞的增殖能力。 相似文献
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湖北松滋早始新世一鸟化石 总被引:1,自引:2,他引:1
本文记述了采自湖北松滋县王家桥区黑档口早始新世洋溪组页岩中一保存较好的鸟化石。依其形态特征归于鹤形目内,但它与已知鹤形目各科又有某些明显的区别,与秧鸡科比较接近。建立一新科:松滋鸟科Songzidae fam. nov.代表我国已知鹤形目化石最早的记录。这一发现还证明始新世早期亚洲东部北纬30°左右已有比较原始的小型鹤形目鸟类分布。本文还讨论了松滋鸟的某些形态功能。 相似文献
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用分离精子进行性别控制研究的现状 总被引:6,自引:0,他引:6
哺乳动物后代性别控制的方法有两种,即植入前胚胎性别的选择和受精前精子的分离,后者是动物性别控制最有效的途径。目前最有重复性、科学性和有效性的分离精子的方法,是根据精子DNA含量存在差异的原理,利用荧光染料与DNA相结合,并通过流动细胞检索分离仪进行精子的分离。 相似文献
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Seidel GE 《Theriogenology》2009,71(1):1-3
Over the past decade, procedures for sexing mammalian sperm by flow cytometry/cell sorting have been refined sufficiently for large-scale commercial application in cattle; millions of doses of sexed sperm are sold each year for artificial insemination. Furthermore, more than a hundred babies are born annually from use of sexed human sperm via artificial insemination or in vitro fertilization, and to a lesser extent by injection of single sperm into oocytes. Semen sexing technology is also being applied for various objectives in a number of other species. Accuracy of sexing is around 90% in most species. However, this technology is still rather expensive, and fertility of sexed sperm is lower than unsexed controls in most instances. Speakers in this symposium, “Update on sexing mammalian sperm,” held in San Diego, California on 3 January 2009, presented the latest research on sexing sperm, including documentation of success rates. The written versions were peer-reviewed and follow in this issue of Theriogenology. 相似文献
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Using the universal P2/P8 primers, we were able to obtain the gene segments of chromo-helicase-DNA binding protein (CHD)-Z and CHD-W from ten species of ardeid birds including Chinese egret (Egretta eulophotes), little egret (E. garzetta), eastern reef egret (E. sacra), great egret (Ardea alba), grey heron (A. cinerea), Chinese pond-heron (Ardeola bacchus), cattle egret (Bubulcus ibis), black-crowned night-heron (Nycticorax nycticorax), cinnamon bittern (Ixobrychus cinnamomeus) and yellow bittern (I. sinensis). Based on conserved regions inside the P2/P8-derived sequences, we designed new PCR primers for sex identification in these ardeid species. Using agarose gel electrophoresis, the PCR products showed two bands for females (140 bp derived from CHD-W and the other 250 bp from CHD-ZW), whereas the males showed only the 250 bp band. The results indicated that our new primers could be used for accurate and convenient sex identification in ardeid species. 相似文献
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对18个猛禽CHD基因的一段内含子序列进行比较和分析.CHD-W和CHD-Z基因的多态性存在差异,CHD-W基因不适合种间系统发生学的研究.通过对CHD-Z基因扩增序列构建的NJ和ML树显示:隼科与其他猛禽物种关系较远;鹰科鸟类与鸮形目鸟类亲缘关系较近;在白腹鹞的分类地位上与传统形态学分类不一致;长耳鸮、领角鸮、花彩角鸮、西部鸣角鸮的分类地位存在分歧.鸮形目和隼形目鸟类的CHD-W基因大小有明显区别,支持形态学分类结果,与CHD-Z序列分析结果明显不同. 相似文献
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Sex assessment of the femur: a test of a new method. 总被引:1,自引:0,他引:1
Simple and multiple discriminant functions using mid-shaft femoral circumference for the determination of sex were used to test a sexing method recently proposed by Black. The method was able to correctly assign sex for 82% of the sample, which consisted of 115 North American White femora of verified age and sex. Circumference proved as accurate as any other criteria that have been used in sexing the femur. This suggests a usefulness beyond the limited archaelogical scope originally proposed by Black. 相似文献
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本研究采用传统的细胞遗传学方法,研究了由流式细胞仪分离的、染色未分离的及作为对照用的未染色未分离的分别来自于3头公牛的精子IVF(in vitro fertilization, IVF)后产生的6~8 d囊胚的染色体异常情况,以确定流式细胞仪分离精子的过程及染色对胚胎染色体异常的影响。结果显示,分离精子、染色未分离精子和未染色未分离精子的胚胎中,染色体组成为异常,即嵌合体的胚胎分别占40.7%(59/145)、35.8%(38/106)和37.0%(37/100),三者染色体异常的比例无显著差异。胚胎染色体异常的频率在不同公牛之间存在差异(33.0% 比 44.6%)(p<0.05)。本研究的结果证明,染料和分离过程没有影响精子的DNA进而影响胚胎的染色体组成;胚胎染色体异常的频率在不同公牛之间存在差异。 相似文献