棕色田鼠第一对常染色体多态与染色体数目关系的研究

研究了棕色田鼠 (Microtusmandarinus)三种性别类型个体 (XY ,XX ,XO)的第一对常染色体多态与染色体数目之间关系 .发现第一对常染色体极不稳定 ,存在( 1 )M ,M (一对中部着丝点染色体 ) ;( 2 )M ,T ,T (一条中部着丝点染色体 ) ;( 3)T ,T ,T ,T(无中部着丝点染色体 )三种多态类型 .性别类型相同个体的染色体数目随第一对常染色体类型的不同发生有规律地变化 .认为罗伯逊断裂是引起棕色田鼠第一对常染色体多态及其染色体数目多态的主要原因     

Somatic deletion and duplication of genes on chromosome 11 in Wilms' tumours

One of the most provocative findings in tumour biology is the relationship between chromosomal changes and embryonal cancers in children. For example, children with the rare paediatric syndrome AGR triad (aniridia, genito-urinary abnormalities and mental retardation) often develop Wilms' tumours at a very early age and carry a germ-line deletion on the short arm of chromosome 11 (11p13). It has been suggested that the germ-line deletion 11p is the first of two or more steps to cancer in AGR children. If this were true, one might expect a similar deletion to arise somatically in the far more common isolated Wilms' tumours of children without AGR, as suggested by Knudson from epidemiological data. However, a chromosomal deletion on 11p was observed in only two of five such cases, while it was absent or seen inconsistently in others. We have now used a molecular genetic approach to determine whether Wilms' tumour cells possess somatic alterations at 11p loci. We have found somatic deletions of specific genes in four of six Wilms' tumours. Surprisingly, in all four cases, the deletions were associated with duplications leading to homozygosity of the non-deleted alleles in the tumour cells. As analogous observations were recently reported in retinoblastoma, the genetic events reported here may underlie the development of many such embryonal tumours in children.     

丝石竹的染色体数目和核型分析

本文对丝石竹(Gypsophila oldhamiana Miq.)的染色体进行了研究,结果显示,染色体数目为2n=34,核型公式为K(2n)=2x=34=32m 2sm,相对长度组成为2n=34=2L 16M2 12M1 4S,核型为“2B”型。     

光果田麻的染色体数目和核型分析

报道了光果田麻(Corchoropsis psilocarpaHarms et Loes.)染色体数目和核型。结果显示,其染色体数目为2n=20,核型公式为K(2n)=2x=20=16m 4sm,相对长度组成为2n=20=10M2 10M1,核型为“2A”型。     

杨树黑斑病菌Marssonina brunnea的有丝分裂过程和染色体数观察(英文)

利用芽管萌发技术(GTBM)对杨树黑斑病菌Marssonina brunnea分生孢子萌发过程中的有丝分裂过程进行了观察,M.brunnea的有丝分裂过程可以分为4个时期:前期染色质逐渐浓缩变短,中期可清楚观察得到染色体,后期姐妹染色单体发生分离并分别向两极移动,末期则可见子核的形成。另外,利用DAPI、DAPI/PI和Giemsa 3种不同的染色方法对染色体进行观察比较,结果表明:Giemsa染色法最适用于M.brunnea;在M.brunnea有丝分裂中期可清楚观察到3条染色体。结合3种染色法,比较分析染色体的绝对值大小和相对值大小,其中相对值大小更加清晰和稳定地描述不同染色体间的变化。     

粗壮女娄菜的染色体数目和核型分析

本文对粗壮女娄菜(Silene firmaSieb.et Zucc.)的染色体进行了研究,结查显示,染色体数目为2n=46,核型公式为K(2n)=2x=46=32m 14sm,相对长度组成为2n=46=2L 22M2 16M1 6S,核型为“2A”型。     

糙叶黄芪的染色体数目和核型

本文研究了黄芪属（Astragalus L.)植物糙叶黄芪（Astragalus scaberrimus Bge.)的染色体。结果显示，染色体数目为2n=16，核型公式K（2n)=2x=16=14m 2sm,染色体相对长度组成为2n=16=8M2 8M1,核型“1A”型。     

流域内区域间取水权初始分配模型初探

分析了河流取水权的特点，提出了区域水权概念，认为水权分配需要考虑的主要因素有现状用水量、理论用水量、投资贡献、水量贡献、政策倾斜、上游优先、水源依赖程度、地区重要性及其他修正等因素。建立的比例型水权分配模型考虑了影响水权分配的各种因素，各种因素的权重通过国家宏观调控政策及政治协商和专家咨询进行赋值，采取了客观指标或专家咨询等手段，确保模型的实用性。最后给出模型的应用示例。     

两类距离图的分式色数和点色数

分式色数和,点、色数是图的两个重要参数.本文在文献[1]的基础上给出了两类距离图G(Z,Dm,k,k+1)与G(Z,Dm,kk+1,K+2)的分式色数和点色数.     

煤层原始含水率对煤与瓦斯突出危险程度的影响

运用自主研发的“含瓦斯煤热流固耦合三轴伺服渗流实验装置”,进行了恒定瓦斯压力和围压条件下,不同原始含水率含瓦斯煤样全应力应变瓦斯渗流试验,结合现场实测煤层注水前后瓦斯涌出量的变化规律。研究结果表明：随着煤样原始含水率的增加,煤样的三轴抗压强度减小,弹性模量减小,三轴抗压强度处轴向应变增大、横向应变和体积应变的绝对值增大;在全应力应变整个过程中,煤样的甲烷有效渗透率都减小。从煤的力学特性和瓦斯在煤层中流动两个方面分析了煤层注水的防突作用。煤层原始含水率越高,发生煤与瓦斯突出的危险性越小。可将煤层的原始含水率作为判断煤与瓦斯突出危险程度的一个重要指标。     

二数列筛法及数的堆垒性和积性的关系

为进一步研究数的堆垒性质,基于爱氏筛法提出一种新的筛法——二数列筛法,运用2种筛法审查数,结果发现一个数被表示为2个素数的倍数之和形状的有关性质及其与数的积性之间存在着必然的关系,进而推导出大于6的偶数与相邻的奇数分别被表示为2个合数之和形状时其解的数量变化的规律,为证明相关的命题提供重要依据。     

Nucleic acid structure and expression of the human AIDS/lymphadenopathy retrovirus

The 9,213-nucleotide structure of the AIDS/lymphadenopathy virus has been determined from molecular clones representing the integrated provirus and viral RNA. The sequence reveals that the virus is highly polymorphic and lacks significant nucleotide homology with type C retroviruses characterized previously. Together with an analysis of the two major viral subgenomic RNAs, these studies establish the coding frames for the gag, pol and env genes and predict the expression of a novel gene at the 3' end of the genome unrelated to the X genes of HTLV-1 and -II.