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1.
钟金城 《西南民族学院学报(自然科学版)》1997,23(1):90-92
根据犏牛雄性不育的研究结果,提出了犏牛雄性不育的多基因遗传不平衡假说.假说认为,不育性是受多基因控制的,牦牛和普通牛由于在多个基因位点上的遗传差异而使犏牛的基因平衡失调,导致不育.最后对该假说的部分证据进行了讨论和分析 相似文献
2.
Fan Yu Jun Xiao XiangYang Liang ShaoJun Liu GongJian Zhou KaiKun Luo Yun Liu Wei Hu YaPing Wang ZuoYan Zhu 《科学通报(英文版)》2011,56(16):1679-1684
Triploid carp (100%) with 150 (3n=150) chromosomes were obtained by crossing the females of improved tetraploid hybrids (♀,
4n=200) of red crucian carp (♀)×common carp (♂) with the males of diploid yellow river carp (♂, 2n=100). The crosses yielded
transgenic triploid carp (positive triploid fish, 44.2% of the progeny) and non-transgenic triploid carp (negative triploid
fish). Histological examination of the gonads of 24-month-old positive triploid fish suggested they were sterile and the fish
were not able to produce mature gametes during the breeding season. Morphologically, both the positive and negative triploid
fish were similar. They had a spindle-shaped, laterally compressed, steel grey body with two pairs of barbells. Most of the
quantifiable traits of the triploid carp were intermediate between those of the two parents. The positive and negative triploid
fish were raised in the same pond for 2 years. The mean body weight of the positive triploid fish was 2.3 times higher than
the negative triploid fish. The weight of the largest positive triploid fish was 2.91 times higher than that of the largest
negative triploid fish. Thus, we produced fast-growing transgenic triploid carp that have a reduced ecological risk because
of their inability to mate and produce progeny. 相似文献
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为探讨中西药结合治疗感染性少、弱精子症疗效,对73例存在不同部位生殖系统感染的少精子症或弱精子症引起的不育症患者应用相应抗生素治疗的同时均给予中药治疗,3个月为一个疗程,间隔3个月后复查精液常规,随访生育情况一年.结果:少精子症组随访中有9例妻子妊娠,妊娠率为33.3%.其中1例因剧烈活动妊娠2个月流产.弱精子症组随访中有17例妻子妊娠,妊娠率为37.0%,其中1例无明显原因妊娠2个月后流产.治疗前、后两组精液各项参数明显改善(P<0.05).说明中、西药结合治疗感染性少、弱精子症起到标本兼治的疗效,少精子症、弱精子症妻子妊娠率均高于自然妊娠率,精液参数明显提高. 相似文献
4.
Summary Recently discovered individuals in New Zealand of the North American speciesDrosophila pseudoobscura were analyzed for any divergence in mating behavior. Cultures collected from five localities in North American were mated with a stock from Rotorua, New Zealand. No significant divergence was obtained in any of the within North Americ, and more importantly, between North American and New Zealand mating experiments. Further analyses also showed no development of sterility between recently caught New Zealand and North American flies. We discuss our results in relation to others of this type.Publication No. 5 from the Evolutionary Genetics Laboratory, University of Auckland.Acknowledgements. We thank the University Grants Committee, grant No. 140Z88, for financial assistance. We thank D.G. Futch., L. Barr, A. Beckenach and H. Spencer for their kind assistance in sending us wild caught cultures. 相似文献
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郑州黑腹果蝇自然群体P—M细胞型多态性研究 总被引:2,自引:0,他引:2
应用性腺败育频率的遗传分析方法,对郑州黑腹果蝇自然群体的P因子活性和细胞型进行了较详尽的剖析。结果发现,该群体的P因子活性是单态的;而细胞型在群体、单雌系内和个体间皆表现出多态现象;该群体为缺乏完整P因子的M′品系。提出了Q因子调控模型,以解释在缺乏完整P因子的M′品系中细胞型决定和多态现象产生的机理,并对细胞型的频率分布规律与平均GD(性腺)不育频率之间的内在联系进行了讨论。 相似文献
7.
Genetic and physical finemapping of the Sc locus conferring indica-japonica hybrid sterility in rice (Oryza sativa L.) 总被引:4,自引:0,他引:4
YANGCunyi CHENZhongzheng ZHUANGChuxiong MEIMantong LIUYaoguang 《科学通报(英文版)》2004,49(16):1718-1721
Hybrid sterility is a major hindrance to utilizing the heterosis in indica-japonica hybrids. To isolate a gene Sc conferring the hybrid sterility, the locus was mapped using molecular markers and an F2 population derived from a cross between near isogenic lines. A primary linkage analysis showed that Sc was linked closely with 4 markers on chromosome 3, on which the genetic distance between a marker RG227 and Sc was 0.07 cM. Chromosome walking with a rice TAC genomic library was carried out using RG227 as a starting probe, and a contig of ca. 320 kb covering the Sc locus was constructed. Two TAC clones, M45EI4 and M90J01 that might cover the Sc locus, were partially sequenced. By searching the rice sequence databases with sequences of the TACs and RG227 a japonica rice BAC sequence, OSJNBb0078P24 was identified. By comparing the TAC and BAC sequences, six new PCR-based markers were developed. With these markers the Sc locus was further mapped to a region of 46 kb. The results suggest that the BAC OSJNBb0078P24 and TAC M45EI4 contain the Sc gene. Six ORFs were predicted in the focused 46-kb region. 相似文献
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