果蝇唾腺染色体观察实验教学的改革与探索

果蝇唾液腺染色体观察实验中,传统的方法因为种种原因效果较差。根据长期的教学实践,对该实验作了一些改革与探索。实践证明,改革后实验材料易获得,步骤简洁,所制装片清晰,取得较好的效果。     

洋葱根尖染色体标本的制备方法

研究了用洋葱(Aillum cepa)根尖为材料制备染色体组型标本的方法与传统用蚕豆(Viciafaba)、玉米(Zeamays L.)等相比较更容易得到分散良好的分裂相。其优点是材料价值低,易获得、易培养,尤其是洋葱的染色体比前几种材料的染色体略大,可获得良好的教学效果。     

兴安天门冬的染色体研究

首次对兴安天门冬（Ａｓｐａｒａｇｕｓ ｄａｕｒｉｃｕｓ Ｆｉｓｈ。ｅｘ Ｌｉｎｋ．）进行了染色体数目和核型研究。结果表明：染色体数目为２ｎ＝１８，核型公式为Ｋ（２ｎ）＝１８＝１０ｓｍ＋８ｍ，核型为“２Ａ”型。     

Construction of the primary physical map of rice chromosome 12

A primary physical map of rice chromosome 12 was constructed using marker-based chromosome landing and chromosome walking. A BAC library from IR64 was screened using 84 RFLP markers, 4 STS markers and 6 microsatellite markers on chromosome 12 by colony hybridization and polymerase chain reaction (PCR) amplification. A total of 59 contigs consisting of 419 BAC clones including 5 single-clones were physically aligned on rice chromosome 12 with the largest BAC contig covering 855 kb. The whole physical map had a size of ∼16 Mb and covered about 52% of rice chromosome 12. This physical map will be certainly helpful for map-based gene cloning of agronomically and biological important genes and understanding the genome structure of the chromosome. Foundation item: Supported by Rockefeller Foundation Biography: FU Bin-Ying (1965-), male, Ph. D. candidate, Reseach direction: plant molecular genetics.     

细胞自动机超并行数据压缩方法

提出细胞自动机元胞级超并行无失真数据压缩方法，并用遗传进化算法获得细胞自动机中的数据压缩规则，证明了细胞自动机文本压缩规则的正确性，讨论了有关的时间复杂性及符号动力学特性。与其他传统的串行或小规模并行的数据压缩方法相比，本文的方法有更好的实时性，普适性，以及Ｓｙｓｔｏｌｉｃ硬件实现的可行性。     

Distribution of sister chromatid exchanges in different types of chromatin in the X chromosome ofMicrotus cabrerae

We used the X chromosomes ofMicrotus cabrerae as a model to analyze the distribution of sister chromatid exchanges (SCEs) on different types of chromatin, because of the marked heterogeneity of the heterochromatin in the entire short arm and a portion of the long arm of this chromosome. Computer-simulated distributions, according to an algorithm that makes it possible to modify the distribution on the basis of any possible hypothesis, were compared with real distributions by log-linear models. We found that the frequency of SCEs in different types of heterochromatin was higher than that expected for a random distribution, and located an SCE hot-spot at the junction between euchromatin and heterochromatin. The possible relationship between the distribution of SCEs and base composition or chromatin accessibility are discussed.     

长期培养的红豆草愈伤组织及其分化芽中染色体变异的研究

对长城１号和埃斯基红豆草在组织培养和原生质体培养中形成的愈伤组织及分化的芽进行了细胞学研究．结果表明，在上述材料中均存在染色体数的变异，其变化范围为７～１１２，主要变异类型是以７为基数的整倍性增减，非整倍性变化的较少．染色体数的变异程度与愈伤组织的性质、培养时间的长短、继代培养中激素的累积浓度以及２，４－Ｄ的浓度有着密切的关系．在丧失分化能力的长城１号红豆草愈伤组织中，正常核型的细胞仅占３３％～３５％；有分化能力的埃斯基红豆草愈伤组织中，正常细胞为４１％～５０％；而在分化的芽中正常细胞数均超过５０％．培养时间越长，激素累积浓度越高，染色体的变异程度越大．在短时间内使用高浓度的２，４－Ｄ进行培养，也可以引起较大的变异．另外，还观察到了染色体结构的各种变异和有丝分裂异常     

低温贮藏对栽培大麦染色体的影响

本文对国家种质自然库中低温下不同贮存年限的３４份栽培大麦种质资源的染色体及其变异进行了探讨。结果显示，种子贮存越久，其染色体的畸变率越高。根尖细胞有丝分裂中期染色体畸变以加倍及断裂为主，有丝分裂后期染色体出现单桥、双桥现象。染色体畸变与种子发芽主之间呈极显著负相关。     

高转移的人卵巢癌细胞遗传学研究

本文对自建的人卵巢癌细胞系（ＨＯ－８９１０）和用该细胞建成的高转移人卵巢癌裸鼠皮下移植癌模型（ＮＳＭＯ）进行了细胞遗传学的比较研究。结果提示：两株细胞均属超二倍体核型，众数为５４条。１、３、１５和２２号染色体常见缺失，１０、１６、１９和２２号染色体常见增加，部分核型中Ｘ染色体有１条缺失，同时发现由１、３、１３、１４和１５号染色体异常而形成的４个标记染色体。ＨＯ－８９１０核型不同的特征是除了４个出现频率较高的标记染色体外，还可见一些其他异常染色体，而ＮＳＭＯ核型中只出现与ＨＯ－８９１０同样的４个标记染色体，很少见有其他异常的染色体，这４个标记染色体可能是高转移卵巢癌独特的遗传特征，这对深入探讨卵巢癌病因和癌变机理有其重要意义。     

Studies inin situ PCR detected by the BrdU antibody technique

Using the BrdU antibody technique followed by an immuno-chemical staining (BAT), the amplification of DNA fragments specific to human Y chromosome on cell specimen slides was efficiently detected. Whether direct BrdU incorporation into PCR products orin situ hybridization with PCR products on slides, the amplified target DNA fragments of specimen were visualized by BAT under the microscope. The availability of BAT and differences in the sensitivity and efficiency between BAT and dig-11-dUTP labeling in cellin situ PCR were discussed. Zhang Xiyuan: born in Oct. 1935, Professor, Current research interest in Cellular and Molecular Biology Supported by the National Natural Science Foundation of China