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利用标记基因选配褐壳蛋鸡配套杂交亲本   总被引:5,自引:0,他引:5  
应用本实验室研制的抗鸡红细胞抗原单价血清(4个位点, 14个等位基因)和DNA指纹技术,对我们组配成功的一个褐壳蛋鸡配套系统的5个亲本进行了群体遗传学分析。结果表明,由标记基因测定所提供的亲本品系遗传差异的大小, 与这些品系实际杂交效果的优劣相一致,证实了标记辅助选种方法有的效性。  相似文献   
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本文应用体外培养人淋巴细胞和小鼠骨髓微核与染色体畸变检测,研究了人胚细胞水提物(胚提物)的遗传毒性和抗突变效应。结果表明,(1)胚提物(3和30μg/ml,下同)可显著抑制培养人淋巴细胞的自发和γ-射线诱发的微核形成;(2)胚提物对培养淋巴细胞的自发染色体畸变无明显影响,但可显著抑制丝裂酶素C(MMC)诱发的染色体畸变; (3)胚提物显著抑制环磷酰胺诱发的小鼠骨髓多染性红细胞微核(PCE-MN)的增加; (4)胚提物的上述抗突变效应呈剂量依赖性增加。因此,作者认为,人胚细胞水提物是一种抗突变剂, 可望用于肿瘤的化学预防,并可用作为肿瘤放疗和化疗的辅助药物,以减少毒付反应和二次肿瘤的发生率。 Abstract:Genetially toxic and antimutagenic effects of the aqueous extracts of human fetal cells(HFCAE) against mutagen-induced chromosomal aberrations and micronucleus formation in human lymphocytes in vitro and bone marrow of mice were studied.HFCAE (3 and 30 μg/ml)significantly inhibited spontaneous and γ-rays-induced micronucleus formation and MMC-induced chromosomal aberrations in human lymphocytes in vitro.HFCAE (3 and 30μg/ml) strongly suppressed also micronucleus formation induced by CP in PCEs of mice.These antimutagenic effects of HFCAE were dose-dependent.Our results suggest that HFCE might be an antimutagen and have potential value in its clinical application.  相似文献   
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在水稻细胞遗传研究中, 对于染色体编号有着较多的争议,这在几条长度较短的染色体上显得尤为突出。为有比较地研究这几条染色体在水稻染色体组中的正确编号,本研究以涉及两条较短染色体相互易位的易位杂合体RT9-12为材料,分析了易位系与普通品种日本晴减数分裂粗线期染色体的形态特征。结果表明,该易位系的易位染色体并非第9和第12染色体,而是第10和第11染色体,从而认为目前国际上统一编号的第9、12染色体,根据染色体的实际长度可能分别为第10、11染色体。 Abstract:Rice chromosomes in mitosis are usually too small to be identified clearly one from others.In recent years,pachytene chromosomes in meiosis have been in vestigated intensively for establishing unified numbering system.However,divergence in numbering system is still existing especially for some short chromosomes such as chromosome 9 and 12.In order to verify these chromosomes,a translocation line RT9-12 and a japonica variety Nipponbare were carefully investigated for all the chromosomes morphologically in late pachytene stage.It was found that the chromosomes involved in translocation were chromosome 10 and 11 in stead of chromosome 9 and 12 as being compared with the karyotype of Nipponbare.So we consider that the chromosome 9 and 12 in the present rice chromosome numbering system could be chromosome 10 and 11 according to their length,arm ratio and the relationship with nucleolus.  相似文献   
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More substances leaked from a higher-vigor seed sample than from a lower-vigor sample. This indicates that, in some cases, electric conductivity does not represent seed vigor level very well, especially for high-vigor seeds. Results from germination, germination index, leachate conductivity, and the ratio of K^+/Na^+ from three-seed lots of Chinese cabbage (Brassica pekinensis (Louv.) Rupr) showed that K^+/Na^+ correlated well with germination and germination index. The ability of K^+/Na^+ to indicate well changes in vigor was further supported by investigation in soybean (Glycine max (L.) Merr.) seeds and another cultivar of Chinese cabbage seeds. Thus, seed leakage of K^+/Na^+ can accurately indicate seed vigor, whereas the conductivity test failed to do so. Furthermore, K^+/Na^+ showed up bigger quantitative differences in vigor level than did the conductivity test. This findings provide a more sensitive and accurate index for the assessment of seed vigor. The mechanisms of Na^+ and K^+ ion transport are also discussed.  相似文献   
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通用线性模型筛选家禽生化多态遗传标记的探讨   总被引:6,自引:2,他引:6  
本研究首次采用线性模型估计生化基因(表)型对产蛋量相关性状的效应,排除环境和遗传背景的差异,检测出效应显著的3种生化基因(表)型。Akp座位F型和Es-1座位AB型的开产蛋重显著降低, 效应的遗传本质有待于深入研究确认。 Tf位点对于36周龄体重的影响不属于基因多效或紧密连锁效应, 可能是距离较远基因连锁的结果,效应随基因间连锁与交换会在品系和世代间产生较大波动;或可能源于非控制误差。本研究还表明生化基因座位与数量性状基因位点(QTL)间的非紧密基因连锁可能大量存在, 但育种意义不大。 Abstract:The literature on associations between biochemical polymorphisms with a Mendelian basis and quantitative traitsis abundant,but it is often difficult to draw conclusions from results that vary in statistical significance and that are sometimes conflicting.Linear models were found capable in estimating associated effects of biochemical genes,precluding deviations due to environmental and population differences.Three biochemical gene- or phenotypes were detected to be significantly associated with laying-related traits.F of Akp locus and AB of Es-1 locus showed large associated effects on egg weight at onset of lay as the result of pleiotrophy or close linkage,or caused by heterogeneity,whereas association of BB at Tf locus with body weight at 36 weeks of age could be due to loose linkage or non-controlled errors which exhibited large variations between populations and possibly through generations Many biochemical loci were also revealed to be occasionally associated with laying-related traits,but few of them could be of breeding importance.  相似文献   
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