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1.
豚鼠精母细胞联会复合体的电镜观察   总被引:3,自引:0,他引:3  
以微铺展法制备豚鼠精母细胞联会复合体标本,经硝酸银染色后作电镜观察,建立了SC组型。与有丝分裂染色体组型比较,发现二者有良好的一致性。在粗线期,X,Y轴的配对区很短,配对区的X轴和Y轴没有明显变细。未发现银染SC具有着丝粒,并对可能的原因做了分析讨论。Synaptonemal complexes (SC) in Guinea pig (Cavia porcellus) spermatocytes prepared with micro-spreading technique and silver staningwere analyzed by electron microscopy.The meiotic SC karyotype was constructed from 7 cells and compared with the mitotic chromosome karyotype. There is a good agreement between them. At pachytene, there is only a very a very short pairing region in which X-and Y-axis are not stinctly thin.The kinetochore thin. The kinetochore was not found on each SC in our experiments and probable reason has been discussed.  相似文献   

2.
苏晓平  徐静  朱志强  孙晓玲 《遗传》1999,21(4):29-30
采用火焰干燥法制备阴道毛滴虫染色体标本,按 Levan等方法,进行核型分析。阴道毛滴虫的染色体数目为n=10,2n =20,染色体的组型为3m、3sm、1st和3T。 Abstract: The chromosomes ofTrichomonas vaginaliswere prepared by flame-drying method. Data of chromosome were measured and calculated. According to Levan's method, analysis of karyotype was described. The results showed that the chromosome number ofT. vaginalisconsisted of twenty pairs(2n=20) and chromosome type was 3m, 3sm, 1st and 3T.  相似文献   

3.
采用火焰干燥法制备阴道毛滴虫染色体标本,按 Levan等方法,进行核型分析。阴道毛滴虫的染色体数目为n=10,2n =20,染色体的组型为3m、3sm、1st和3T。 Abstract: The chromosomes ofTrichomonas vaginaliswere prepared by flame-drying method. Data of chromosome were measured and calculated. According to Levan's method, analysis of karyotype was described. The results showed that the chromosome number ofT. vaginalisconsisted of twenty pairs(2n=20) and chromosome type was 3m, 3sm, 1st and 3T.  相似文献   

4.
ZHUJM  LJDAVIES 《Cell research》1994,4(1):65-68
The somaclone,C39,derived by tissue culture from the obligate apomict Paspalum dilatatum cv Raki(2n=50),had 50 chromosomes and a karyotype apparently identical to Raki.SC2 seedlings of C39 showed a high degree of phenotypic variation which was often associated with increased chromosome numbers,but some of the variant seedlings were karyotypically indistinguishable from Raki or C39.Plants with increased chromosome numbers exhibited a high degree of intraplant chromosome variation(aneusomaty).In one of the SC2 seedlings,the chromosome number of root tip cells varied from 58 to 82 and in several other seedlings the range was more than 10.The results suggested that the ability to form seed apomictically was much reduced in C39 and that this plant showed some capacity for sexual reproduction and the resulting seedlings,with a chromosome number of about 70,were genetically unstable.Of 11 SC2 seedlings examined cytologically,6 did not produce any viable seed.Seedlings grown from seed of the remaining 5 plants showed that aneusomaty persisted in the SC3 generation.SC3 seedlings which were phenotypically similar to their maternal parent showed a similar range of chromosome numbers to that parent.Some of the SC3 seedlings exhibited an even wider range of chromosome numbers(e.g.56-136),and these plants were all dwarfs.  相似文献   

5.
一个13/21染色体罗伯逊易位家系中, 易位染色体携带者4人,易位型先天愚 型患者3人,易位染色体至少已经遗传了4代。该家系中有同性双生子的聚集现象。讨论 了罗伯逊易位的遗传机理。 Abstract:A pedigree with 13/21 robertsonian translocation was reported.There were four carriers and three patients with Downs syndrome in the padigree.The Robertsonian chromosome translocation had been transmitted at leart for four generations.A family aggregation of monozygotic twines was found in this pedigree too.The inheritance principle of robertsonian translocation was discussed and that the origin of monozygotic twins may be genetically involved were considered.  相似文献   

6.
水稻染色体形体较小, 很难从形态上区分各别染色体。尽管有许多学者报道了水稻核型的研究结果, 但不同学者之间的分歧依然存在。本文对不同学者所作核型进行了分析, 从而对现行的水稻染色体编号系统提出了新的看法。 Abstract As rice chromosome is very small, it is difficult to identify morphologically the individual chromosome from rice chromosome complement. Although many studies have been conducted on the karyotype of rice, controversies still exist among different researchers. The present paper summerized the data of rice karyotype given by different researchers, and some suggestions were also proposed on rice chromosome numbering system.  相似文献   

7.
In order to precisely recognize and karyotype Brassica napus L. chromosomes, C0t-1 DNA was extracted from its genomic DNA, labeled with biotin-1 1-dUTP and in situ hybridized. The hybridized locations were detected by Cy3-conjugated streptavidin. Specific fluorescence in situ hybridization (FISH) signal bands were detected on all individual chromosome pairs. Each chromosome pair showed specific banding patterns. The B. napus karyotype has been constructed, for the first time, on the basis of both Cot-1 DNA FISH banding patterns and chromosome morphology.  相似文献   

8.
对家猪不同品种及家系间的染色体组型、C-带、Ag-NORs多态性进行的研究表明:杜洛克猪、约克夏猪、长白猪体细胞染色体数2n=38,核型2n=10sm+12m+4st+12t, 而13/17易位纯合子猪(36, rob. 13/17)的体细胞染色体数2n=36,核型2n=10sm+12m+6st+8t; 13/17易位杂合子猪(37,rob. 13/17)的体细胞染色体数目为 2n=37,核型为2n=10sm+12m+5st+10t。5种家猪的C-带在13~18号染色体上存在大、中、小三种类型, 且呈多态性分布。杜洛克猪、约克夏猪、长白猪、13/17易位纯合子猪、13/17易位杂合子猪的Ag-NORs均数分别为2.05、2.06、2.00、1.99、1.98,说明Ag-NORs在品种、个体及细胞间具有多态性。 Abstract:The present experiment is carried out to make comparative stdy on polymorphism of chromosome Karyotypes, C-band ?and Ag-NORs of different breeds and strains in domestic Pigs. The results showed that the chromosome number of somatic cell in Duroc, Yorkshire and Landrace Pig Was 38 and the karyotype was 2n=10sm+12m+4st+12t. But in heterozygous Rob 13/17(37, rob. 13/17) Pig, the chromosome number of somatic cell was 37 andthe karyotype was 2n=10sm+12m+5st+10t, while in homozygousRob 13/17(36, rob. 13/17) Pig, the somatic cell chromosome number was 36 and the karyotype was 2n=10sm+12m+6st+8t. It was also showed that there were three C-band types in size on chromosome No. 13-18 showing polymorphism in three breeds and two strains of domestic Pigs. The average of Ag-NORs in Duroc, yorkshire,Landrace, homozygous Rob. 13/17 and heterozygous Rob. 13/17 Pig was 2.05, 2.06, 2.00, 1.99 and 1.98, respectively. It is suggested that Ag-NORs have polymorphism among strains, which can be used as a genetic index to analyse relationships among domestic animals with high reliability.  相似文献   

9.
大鳞副泥鳅ZZ/ZW型性别决定的细胞遗传学证据   总被引:13,自引:1,他引:12  
大鳞副泥鳅是鲤形目、鳅科的鱼类。其2n数为48,核型组成为12m+4sm+32 t(雄性),11m+5sm+32t(雌性)。根据银染带和C带特征分析,证实大鳞副泥鳅为ZZ/ZW型性别决定。Z染色体为中部着丝粒染色体,在其长臂端部有Ag -NOR存在。 W染色体为亚中部着丝粒染色体,在其长臂末端也有Ag-NOR存在,同时还有一深染的居间C带,这是W染色体独有的带纹特征。 Abstract:Paramisgurnus dabryanus belongs to Cypriniformes,Cobitidae.Its 2n is 48.The karyotype formula is 12m+4sm+32t(in male),11m+5sm+32t(in female).According to the Ag-NORs band and C-band patterns,we consider that its sex determination is of ZZ/ZW type.The Z chromosome is a metacentric one with Ag-NORs located on its arm end.The W chromosome is a submetacentric with Ag-NORs located on the terminal of its long arm.There is a darkly stained C-band on the long arm of W chromosome.This band is a characteric of the W chromosome.  相似文献   

10.
用FISH技术对人、恒河猴、食蟹猴染色体的研究   总被引:7,自引:1,他引:6  
用人类5号、 9号、13号、15号、17号、20号整条染色体探针分别对人、恒河猴和食蟹猴的中期细胞进行荧光原位杂交,结果表明:人的5号、13号、17号探针分别杂交到恒河猴的5号、16号、17号染色体上;9号探针杂交到恒河猴14号染色体的长臂及部分短臂上; 15号探针杂交到恒河猴7号染色体短臂及部分长臂上;20号探针杂交到恒河猴的13号染色体长臂上。食蟹猴的杂交结果与恒河猴完全一致。结合G带带型分析,对人与猕猴的染色体同源性及其进化进行了讨论。 Abstract:Fluorescent in situ hybridizaiton(FISH)was used on the metaphase of Macaca mulatta and Macaca fasicularis with human chromosome specific DNA libraries for chromosome 5、9、13、15、17 and 20.In Macaca mulatta,the result showed that chromosome 5、16 and 17 was entirely painted by human chromosome 5、13 and 17 specific libraries respectively.The long arm and the partial short arm of chromosome 14 and the short arm and the partial long arm of chromosome 7 were painted by human chromosome 9 and 15 specific libraries respectively.And the long arm of chromosome 13 was painted by human chromosome 20 library.The result was the same in Macaca fasicularis.Combinded with the comparative analysis of G-banding,the evolutional relationship of these chromosomes between human and macaques was discussed.  相似文献   

11.
以微铺展法制备豚鼠精母细胞联会复合体标本,经硝酸银染色后作电镜观察,建立了SC组型.与有丝分裂染色体组型比较,发现二者有良好的一致性.在粗线期,X,Y轴的配对区很短,配对区的X轴和Y轴没有明显变细.未发现银染SC具有着丝粒,并对可能的原因作了分析讨论.  相似文献   

12.
中国人精母细胞和卵母细胞联会复合体的电镜观察   总被引:4,自引:0,他引:4  
施立明  马昆 《遗传学报》1992,19(5):403-409
以微铺展技术结合硝酸银染色,对中国人精母细胞和流产胎儿卵巢联会复合体的形态和行为作了电镜观察。列出中国人的SC核型和模式图。根据减数分裂前期XY的复杂形态变化,XY的配对可分为5种类型。对XY短臂之间形成的SC和XY长臂顶端的次级联合以及XY配对的性质和机理作了描述和讨论。本文还报道了一个罕见的三倍体精母细胞,对三倍体精母细胞中SC的配对行为以及和人类染色体疾病病因的可能关系作了分析和讨论。  相似文献   

13.
本工作以C带、硝酸银染色、对黑眉锦蛇(Elaphe taeniura)的有丝分裂染色体进行了显微观察。其二倍体染色体数目2n=36,核型组成为16(8m+6sm+2t)大染色体+20微小染色体。C带显现于几乎所有染色体的着丝粒区,有一对插入型C带位于第6对端着丝粒染色体。一个银染核仁组织区(NORs)位于No.12小染色体。同时以界面铺张——硝酸银染色技术,对黑届锦蛇减数分裂精母细胞联会复合体(SC)的结构进行了亚显微观察。发现黑眉锦蛇的SC结构与其他动物的SC相似,是由两股平行的侧线组成,SC组型与有丝分裂染色体组型有较好的一致性。  相似文献   

14.
长毛红山茶和长尾红山茶的核型分析   总被引:4,自引:0,他引:4  
<正> 长毛红山茶(Camelliav uillosa Chang et S.Y.Liang)和长尾红山茶(C.longicaudata Chang et S.Y.Liang)均为张宏达教授定的新种,分别隶属于山茶属(Camellia)红山茶组(Sect.Camellia)的滇山茶亚组(Subsect.Reficulala)和光果红山茶亚组(Subsect.Lucidissima),前者分布在我国的湖南、广西和贵州,后者分布在广东和广西。 红山茶组共有33个种、1个亚种,7个变种。根据文献资料统计,该组作过染色体计数的有10个种,1个亚种和6个变种,作过核型分析的有4个种、1个亚种和2个变种。本文对该组的长毛红山茶和长尾红山茶的核型作首次报道,并与该组的10个种,1个亚种和6个变种的染色体数目或核型作了比较。  相似文献   

15.
长鬣蜥的染色体组型和减数分裂联会复合体的研究   总被引:2,自引:0,他引:2  
王蕊芳  贺维顺 《遗传学报》1993,20(3):211-215
本文报道长鬣蜥(Physignathus cocincinus)有丝分裂染色体及C-,Ag-带以及减数分裂联会复合体核型。染色体数2n=36,NF=48,核型组成为12V+24m(V为双臂大染色体,其中No.2为亚中着丝粒染色体,m为微小染色体)。结构异染色质主要分布在小染色体上。一对Ag-NORs分布于第2对亚中着丝粒染色体末端。  相似文献   

16.
西藏巨柏核型的图象自动分析与识别的研究   总被引:1,自引:0,他引:1  
我们应用图象自动分析和识别的原理和方法,建立了植物染色体自动分析CHROMHUK软件系统,并首次对西藏巨柏进行了核型自动分析,抽取了染色体多个特征多数:相对长度、臂比、着丝点指数、相对体密度和次缢痕相对长度.对247个巨柏体细胞进行多参数数据统计和分析,并设置95°.置信判别区域和树分类判别.实现了染色体自动配对和分类,并由计算机直接输出染色体的组型图和核型模式图.分析结果表明:巨柏体细胞的染色体数目为2n=22,按Levan的分类标准,其核型公式为2n=4m(SC)+16m+2sm.据Stabbins分类为1A型.  相似文献   

17.
The diploid chromosome number of the Chinese raccoon dog varies from 54 (no B chromosomes) to 58 (4 B chromosomes). The B chromosomes are totally heterochromatic. An electron microscopic study was made of the synaptonemal complexes (SC) in spermatocytes of these animals. The SC karyotype consists of 27 regular chromosome pairs (autosomes and the sex chromosomes) plus the B chromosomes. The Bs pair effectively with one another at pachytene, but the SC axes of the B chromosomes are much denser than those of the A chromosomes. Depending on the number of Bs, both bivalents and multivalents have been observed. When three B chromosomes are present in a cell, parallel alignment of all three SCs can be seen. Formation of multivalents indicates high homology among these supernumerary heterochromatic chromosomes. Fusiform bulges are found along unpaired regions of all chromosomes which are particularly pronounced in diplotene.  相似文献   

18.
A detailed account is presented of attendant polysomatic variation in planta and elucidation of the modal karyotype in the difficult-to-study endangered orchid Bulbophyllum auricomum, known as the Royal Flower of Myanmar. The somatic chromosome number of B. auricomum (2n?=?38) is reported for the first time. Polysomaty was prevalent in all seed-derived plants studied except two (SC34 and SC42). It was noted that in addition to normal diploid cells occurring in different frequencies (60% in SC21 to 89% in SC22, SC35), root tip cells also showed chromosome numbers <38 (in 0?C37% metaphases) and >38 (in 0?C33% metaphases). The chromosomes of B. auricomum are very small (0.7?C2.7???m) in size. The karyotype of diploid B. auricomum showed 34 chromosomes with primary constriction (14?M?+?16?m?+?4sm) and 4 chromosomes with secondary constrictions (sm:sm). Of the 50 plants analyzed, 2 (SC34 and SC42) were polyploid, showing 70 and 62 chromosomes in the root tip cells. The polyploidization in seed-derived plants clearly indicates the heterogeneous nature of orchid seed stock. Early detection of polyploidization in in vitro?Cpropagated B. auricomum is valuable for conservation of this native endangered orchid species. On the other hand, the clonally propagated plants retained the chromosomal status of parent plants. This protocol could be exploited to protect this native endangered orchid species from natural extinction.  相似文献   

19.
作者以去污剂铺展——硝酸银染色技术,对家蚕普斑限性及虎斑限性品系雌蚕的联会复合体进行亚显微观察分析,未发现品系有异形ZW;但在品系中发现ZW呈现明显的末端不对称性。联会复合体分析表明该品系的ZW两侧线的相对长度相差达5.2%,较长的侧线为Z染色体,较短的侧线是断裂后的W染色体和第Ⅳ连锁群带有Ze片染的相互转座。ZW-SC在晚粗线期开始分离,较其他SC分离显著提前。这可能与易位导致ZW的不同源区段增长有关。  相似文献   

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