染色体

The results of our study have demonstrated that,(1) quadrivanlents in diakinesis Ⅰ are ideal materials for micromanipulation;(2) compared with the instrument used to microisolate chromosomes with a dissecting needle perched on a dissecting microscope outfitting with a micromanipulator or laser beam, the equipment most common used in our study is relatively inexpensive and the techniques could be established as a standard procedure in the ordinary laboratory;(3) the gene mapping methods developed in the study is an efficient and fast approach that could advance gene mapping of fish and other species.

本研究结果表明，（1）减数分裂Ⅰ终变期染色体标本是进行染色体显微操作研究的理想材料；（2）与显微操作仪和微激光分离相比较，本研究所探索的显微分离染色体方法不需要昂贵仪器，在常规实验室即可操作，具有广泛的普及应用意义；（3）把染色体显微操作应用于基因定位这种构思是完全可行的。这种基因定位方法简明而快捷，从而为鱼类及其它物种染色体定位研究开辟了一个新的研究方式和途径。

The results of the karyotype analysis indicated that the heteromorphic sex chromosomes existed in mitotic prometaphase chromosomes of the early embryos. Zchromosorne was the longest among the total of 56 chromosomes, and usually had twoconstricts at the ...

经对23个分散好、完整的分裂相的分析表明：家蚕早期胚胎有丝分裂早中期染色体中有异型性染色体存在，Z染色体是核型中最长的，通常具有亚端和亚中部次缢痕，W染色体很短，约相当干Z染色体的1／3长。

The misdivision ofunivalents that resulted in the formation of telocentrics,iso-chromosomes and translocated chromosomes was the mainvariation pattern of chromosome structure.

单价体错分裂导致端体，等臂染色体和易位染色体的形成，是染色体结构变异的主要方式，离体培养诱发染色体缺失，是染色体结构变异的有效补充手段，从而成为有目的，有计划的向小麦导入外源有用基因的有效途径。

Results showed that the PMC meiosis of autotetraploid was similar to the diploid except some particularities. In metaphase Ⅰ, multivalent, quadrivalent, trivalent, bivalent and univalent were observed and some of the chromosomes were found not to rank on the metaphase plate and so did in metaphase Ⅱ cells. In anaphase Ⅰ and anaphase Ⅱ cells, there were lagging chromosomes, chromosome bridge and fragment. During anaphase Ⅱ and telophase Ⅱ, chromosome segregation was not synchronous or equal. At tetrad stage, dyad, triad, tetrad with micronucleus and polyad appeared.

结果表明，同源四倍体花粉母细胞减数分裂过程与二倍体相比，中期Ⅰ染色体构型复杂，有多价体、四价体、三价体、二价体和单价体；中期Ⅰ及中期Ⅱ有部分染色体没有排列在赤道板上；后期Ⅰ及后期Ⅱ出现落后染色体、染色体桥及断片；后期Ⅱ和末期Ⅱ有染色体不同步分离及不等分裂的现象；四分体时期还出现二分体、三分体、含微核的异常四分体及多分体。

B chromosomes are also called supernumerary chromosomes, accessorychromosomes or extra chromosomes. They are supernumerary to the standardchromosomes set, which are found in thousands of plants andanimals.

B染色体又称超数染色体、附加染色体或额外染色体，是在生物界中广泛存在的一种特殊染色体。

Primary culture and subculture were adopted using lung cells of a female Elaphodus cephalophus' embryo. A new karyotype and a pair of big telocentric chromosomes were found. The diploid has 48 chromosomes, and the karyotype formula is 2M+2ST+42T+XX. C-banding analysis shows that these chromosomes are homologous with those reported relevant chromosomes. This article is the first to report the polymorphism of Elophodus cephalophus B-chromosomes and studies it's transmitted mechanism.

采用原代培养和传代培养法，对1头毛冠鹿的胚肺组织细胞进行观察，发现一种新的核型，其二倍体染色体数目为2n=48，核型公式为2M+2ST+42T+XX，出现1对大的末端着丝粒染色体，C-带显示该染色体与已报道的相关染色体同源，首次提出毛冠鹿B染色体多态，对其传递机制进行了探讨。

Five pairs of 45S rDNA loci and two pairs of 5S rDNA signals were detected on chromosomes of Cucurbita moschata Duch. Luffa cylindrical Roem. contained five pairs of 45S rDNA loci and one pair of 5S rDNA loci. In Benincasa hispida Cogn., two pairs of 45S rDNA sites and one pair of 5S rDNA site were detected. In this species, 5S rDNA and one pair of the 45S loci were collocated closely in chromosome 7S. 45S rDNA chromosomal distribution patterns were highly conserved among the three species, althoufh their number varied markedly. The 5S rDNA sites on chromosomes among the three species were highly polymorphic.

南瓜有5对45S rDNA位点， 2对5S rDNA位点；丝瓜具有5对45S rDNA位点， 1对5S rDNA位点；冬瓜具有2对45S rDNA位点， 1对5S rDNA位点， 5S rDNA位点与其中一对45S rDNA位点都位于7号染色体短臂上，并在物理位置上紧密相邻。45S rDNA在这3种作物染色体上数目变化较大，但在染色体上都倾向分布在短臂末端，其分布模式较为一致。5S rDNA在这3种作物染色体上数目相对保守，但在染色体上分布的位置变化较大。

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.

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。

The formula of chromosome karyotype of A. heterophyllum was 2n=28=18m+10sm, its chromosome relative length was in the range of 24.464%-63.245%, the ratio of the longest chromosome to the shortest chromosome was 2.58 and the chromosomes with arm ratio above 2:1 accounted for 14.3% in total chromosomes.

异叶天南星的染色体核型公式为2n=28=18m+10sm，其染色体相对长度在24.464%~63.245%的范围内，最长染色体与最短染色体的比值为2.58，臂比值大于2：1的染色体占总染色体的14.3%。

All lines showed a chromosome number of 2n = 42, five of them carried botha pair of wheat-rye (Triticum aestivum-Secale cereal ) 1BL/1RS translocation chromosomes and a pair ofAgropyron intermedium chromosomes, three carried a pair of Ai chromosomes only, three otherscarried a pair of 1BL/1RS chromosomes only, and one carried neither 1BL/1BS nor Ai chromosome.

结果表明，12份材料染色体数均为42，其中5份材料均具有一对小麦-黑麦(Triticum aestivum-Secalecereal)1BL/1RS易位染色体和一对中间偃麦草染色体、3份材料只具有一对中间偃麦草染色体、3份材料只具一对1BL/1RS染色体、1份材料无1BL/1RS和中间偃麦草染色体。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。