Buckton等（1985）认为额外小染色体（extra small chromosome）有时对表型可无显著影响,但对不同的个体与群体可能有所不同,这种染色体不依孟德尔法则遗传,大多数缺乏常染色质与主要基因,对生育可能产生有害的影响。不同报告中认为额...Buckton等（1985）认为额外小染色体（extra small chromosome）有时对表型可无显著影响,但对不同的个体与群体可能有所不同,这种染色体不依孟德尔法则遗传,大多数缺乏常染色质与主要基因,对生育可能产生有害的影响。不同报告中认为额外小染色体对智力迟钝（mental retardation）与不育有关。Soudek等（1977）将额外小染色体分为活动型与非活动型两大类,即以非活动型而论,虽然经过多代遗传,一般对携带者无影响,但偶尔仍不能排除其有损于携带者的一面。展开更多
A simple and efficient method is described for chromosome preparations from chorionic villous sample in the first trimester. We Jound that hypotonic treatment, proper colchicine and fixative time are interactive jacto...A simple and efficient method is described for chromosome preparations from chorionic villous sample in the first trimester. We Jound that hypotonic treatment, proper colchicine and fixative time are interactive jactors, which have important bearings on the quality of chromosomes. Chromosomes of the cells of the cytotrophoblast prepared by this method appear adequately spreading, and could be successfully used in 124 cases of prenatal diagnosis. The number of metaphase and analysable metaphase in short term culture method was significantly increased as compared with that of the direct method ( P<0.01, P<0.01). On the basis of the data of 50 eases analysis, there was linear dependence between the metaphase number and days of gestation, linear independence between the metaphase number and weight of chorionic villi.展开更多
文摘Buckton等（1985）认为额外小染色体（extra small chromosome）有时对表型可无显著影响,但对不同的个体与群体可能有所不同,这种染色体不依孟德尔法则遗传,大多数缺乏常染色质与主要基因,对生育可能产生有害的影响。不同报告中认为额外小染色体对智力迟钝（mental retardation）与不育有关。Soudek等（1977）将额外小染色体分为活动型与非活动型两大类,即以非活动型而论,虽然经过多代遗传,一般对携带者无影响,但偶尔仍不能排除其有损于携带者的一面。
文摘A simple and efficient method is described for chromosome preparations from chorionic villous sample in the first trimester. We Jound that hypotonic treatment, proper colchicine and fixative time are interactive jactors, which have important bearings on the quality of chromosomes. Chromosomes of the cells of the cytotrophoblast prepared by this method appear adequately spreading, and could be successfully used in 124 cases of prenatal diagnosis. The number of metaphase and analysable metaphase in short term culture method was significantly increased as compared with that of the direct method ( P<0.01, P<0.01). On the basis of the data of 50 eases analysis, there was linear dependence between the metaphase number and days of gestation, linear independence between the metaphase number and weight of chorionic villi.
