葱小孢子的染色体和核型研究

本文用胰酶－尿素双重处理法和ＳＳＧ法,分别进行了葱小孢子染色体螺旋的染色体Ｃ－带的显带研究。首次成功地获得了葱小孢子染色体螺旋和染色体Ｃ－带,螺旋图象清晰;染色本Ｃ－带与体细胞的基本一致,所有染色体上均显示出明显的末端带,但未出现次缢痕带,另外,研究了葱小孢子的核型,其结果与体细胞的核型基本一致,但有差异。作者认为小孢子的核型比体细胞的核型准确,更能反映出葱的核型特征。     

河南花背蟾蜍的核型、C-带和Ag-NORs研究

利用骨髓细胞蒸汽固定法制备染色体标本,研究了分布于河南新乡的花背蟾蜍(Bufo raddei)的核型、C-带和Ag-NORs。结果表明：河南产花背蟾蜍体细胞染色体数为22条,核型公式为2n=22(20m 2sm),全部为中部或亚中部着丝点染色体,NF=44。Ag-NORs具有多态现象。C-带核型显示22条染色体的着丝点均正染,No．1染色体近着丝粒处有不恒定插入型C-带,No．4染色体具有恒定近端部插入型C-带,随体部位被正染的仅占所观察细胞的15％。     

新疆裸重唇鱼染色体的核型及C-带研究初报

探索新疆裸重唇鱼的染色体数目和核型,并对新疆裸重唇鱼染色体进行C带型的描述和分析,填补领域内对这一物种研究的空白,为后续的研究打下基础。采用PHA体内注射肾细胞直接制片法研究新疆裸重唇鱼的核型,采用改进的BSG法来研究其C-带。结果表明,新疆裸重唇鱼的核型公式为2n=98=28m＋30sm＋12st＋28t,臂数NF=156。m1、sm1、sm2、t1和t2明显比同组其他染色体大,未发现小染色体及其他异型性染色体。C-带较丰富显示出3种类型的C-带,所有染色体都有着丝粒带,部分有端粒带,有些染色体两端都有端粒带,有些只有一端有端粒带,sm5、sm12和t 3还显示深浅不一的居间带。并通过与同亚科种类进行对比分析,讨论它们的亲缘关系和系统演化。     

黑斑蛙核型、C-带及Ag-NORs 研究

本文采用外周血淋巴细胞培养法制备染色体标本,观察黑斑蛙的染色体标本,研究黑斑蛙的核型,C-带和Ag-NORs。研究结果表明：（1）黑斑蛙淋巴细胞染色体数目为2n=26,其中有5对大染色体和8对小染色体,核型是二型性核型;（2）分别对雌雄个体的中期分裂相进行观察,在第11号染色体长臂中部有明显的次缢痕,但变异核型次缢痕在第8号染色体长臂的中部;（3）在第5号染色体长臂上有一条明显的近端粒C-带;（4）第11号染色体是一对具有银染核仁形成区的同源染色体,且雌雄个体的银染位置相同。     

底栖类球蛛的核型分析（蜘蛛目：类球蛛科）

第1次报道底栖类球蛛的核型分析,包括染色体数目、形态结构和性染色体组成。实验结果表明底栖类球蛛的染色体数目是:雄性体细胞染色体数为2n=22,雌性体细胞为2n=24,性决定机制为X_1X_2O系统,X染色体为最小的和次最小的,5~＃染色体为随体染色体;对C-标本分析表明,染色体均为端或亚端着丝粒染色体,各染色体C-带带纹有识别特点。     

准噶尔雅罗鱼染色体核型及带型的初步研究

以肾细胞作材料,采用秋水仙素-低渗-空气干燥法、Ag-NORs、C-带和G-带显带技术对准噶尔雅罗鱼(Leuciscus merzbacheri)染色体进行了研究。结果表明:(1)准噶尔雅罗鱼2n=50,核型组成为18m+14sm+6st+12t,NF=82,没有异型性染色体分化。(2)Ag-NORs的数目在不同的细胞中表现出多态性,数目为1～2个,出现1个Ag-NORs的频率最低(10%),出现2个的频率最高(70%);Ag-NORs主要出现在m1对和m4对同源染色体上;未发现有Ag-NORs联合的现象。(3)准噶尔雅罗鱼的染色体均呈现C-带阳性,可分为着丝粒C-带和端粒C-带。(4)同源染色体上G-带带纹基本一致,其带纹在每对染色体上的数目及分布具有明显特征性。     

二倍体多年生类玉米及其与玉米的杂种的染色体Giemsa C-带的研究

利用Giemsa C-带显带技术分析亲本及其杂种体细胞有丝分裂中期核型的结果表明,二倍体多年生类玉米的大多数显带都在染色体的长臂末端,第1、2、9染色体的短臂末端也显带。所显现的带纹比玉米的稍小些。这些是与玉米不相同的。玉米除第9染色体的短臂末端显带外,其他染色体均为长臂近末端显带。根据两个亲本的同源染色体Giemsa C-带带型的特点表明,在杂种F_1的体细胞中,能够鉴别出来一组染色体来自父本二倍体多年生类玉米和另一组染色体来自母本玉米。作者还讨论了Giemsa显带技术在植物细胞遗传学特别是玉米细胞遗传学上的利用价值和重要性。     

黑线姬鼠华北亚种染色体研究

本文采用骨髓染色体制片法,对分布于山东的黑线姬鼠华北亚种的染色体组型,C-带、G-带和银染核型进行了分析研究。其核型为2n=48=38 T+8 M+XY。X为较小的端着丝粒染色体,Y为组型中最大的染色体。几乎每个常染色体的着丝粒区都具异染色质。性染色体的异染色质丰富。No.10和No.18染色体具NOR(?)。每条染色体都显示出较清晰的G-带。同时对黑线姬鼠精母细胞的减数分裂进行了观察,并将山东标本与欧洲标本的核型进行了比较,其性染色体有显著差异。     

牛蛙(Rana catesbeiana)染色体研究

对牛蛙（Rana catesbeiana,Shaw）的染色体组型进行了研究。观察骨髓的C-中期细胞,结果证明牛蛙的体细胞染色体数目2n=26,其中有5对大型染色体和8对小型染色体,可以分成A、B、C3个组,雌性和雄性个体间没有发现异型性染色体。上述结果与前人的研究结果基本一致。但是作者发现牛蛙骨髓细胞的第7、8、10、12号染色体上均有次缢痕。牛蛙的核型为2n：26=22m＋4sm。     

中国刺猬的染色体研究

本文采用全血培养和骨髓染色体制片法,对分布于我国南京市郊和济南市郊的刺猬染色体进行了组型、C-带、G-带和银染色的观察分析,并与东欧、西欧两种刺猬比较,它们之间的核型及带型差异显著;又将南京、济南及金清波(1985)报道的河南新乡三地分布的刺猬进行比较,它们的核型及带型也显示出一定差异,这种多态性在分类和进化上有一定的意义。     

Evidence for chromosome number reduction and chromosomal homosequentiality in the 24-chromosome Korean frog Rana dybowskii and related species

The karyotype of the Korean frog Rana dybowskii with its pattern of C-band heterochromatin distribution was numerically analyzed. There are 2n = 24 chromosomes in the karyotype representing a reduction in number from the typical 2n = 26 chromosome karyotype of Rana. The karyotype shows other evidence of reorganization relative to 26-chromosome species. The chromosomes grade smoothly in size from largest to smallest without the two size classes that are characteristic for 26-chromosome species. In contrast to many 26-chromosome species, there are few centromeric C-bands but many interstitial ones. C-bands for each homologous chromosome pair are distinctive. A prominent secondary constriction is located on one of the smallest chromosomes, chromosome 11, in a position similar to that seen in most 26-chromosome species. The karyotype of R. dybowskii is compared to those of other species of Rana known to have 2n = 24 chromosomes; it is most similar to that of R. chensinensis, less so that of R. ornativentris and less still to that of R. arvalis in terms of the positions of centromeres and secondary constrictions. C-bands as well as secondary constrictions in the karyotypes of these frogs show evidence of chromosomal homosequentiality. The process and possible consequences of chromosome number reduction from an ancestral 26-chromosome karyotype is also evident in the karyotypes of these closely allied palearctic frogs. Pericentric inversions followed by fusion of two small elements apparently produced a new chromosome, chromosome 6, occurring originally among northeast Asian populations.     

A new karyotype in Callicebus torquatus (Cebidae, Primates)

We describe a new karyotype of Callicebus torquatus using conventional staining, G-banding with Wright Stain, CBG, Ag-NOR staining and fluorescence in situ hybridization (FISH) with human telomere probes and comparative analysis with the previously reported karyotype of C. torquatus torquatus (2n = 20). We studied a female specimen maintained in captivity at the Centro Nacional de Primatas (Para, Brazil). This titi monkey presented 2n = 22, with four large biarmed and six acrocentric autosome pairs; the X chromosome is a medium submetacentric. C-bands were revealed at the centromeric region of all acrocentrics and X chromosome; punctual C-bands also are visualized at the centromeric region in the large biarmed pairs. The NOR site was located at the long arm of pair 4, at the position of a conspicuous secondary constriction. Hybridization signals were detected exclusively at the terminal region of all chromosomes. The karyotype described here has one acrocentric pair more than that found in the literature and also differs by amount and distribution of constitutive heterochromatin. Our data support the notion that the torquatus group may be composed of distinct species, each with its own karyotype.     

鼷鹿云南亚种（Tragulus javanicus williamsoni）的核型分析

本文以染色体分带技术,发现鼷鹿云南亚种的染色体数目为2n=32。全部为双胃染色体,NF=64。所有染色体着丝点区分布有C带,多数染色体的端部或两端也有C带。某些染色体还有插入C带。Y染色体C带阳性,有一Ag-NORs。文章对鼷鹿云南亚种染色体独特的C带分布以及和核型进化的关系进行了讨论。     

茅舍血厉螨核型及染色体的C带、G带的研究

本文首次报道了一种革螨——茅舍血厉螨核型及染色体C带、G带的研究。用剖腹取卵法、玻璃纸压片、Giemsa染色,经分析茅舍血厉螨的核型,单倍体n=7,二倍体2n=14。 用氢氧化钡—吉姆萨技术显示茅舍血厉螨染色体C带。在第1、2、4、5染色体上出现恒定的C带部分,第3、6、7染色体上出现不恒定的C带部分。根据C带带型,茅舍血厉螨着丝点的位置可分为近中区域(sm),近端区域(St),末端区域(t)和末端点(T)四类。 G带分析用胰蛋白酶—吉姆萨技术显示。 本文对茅舍血厉螨的核型、革螨染色体研究中螨卵的收集方法和染液的改进、C带带型与着丝粒位置的确定和G带显带问题进行了讨论。     

Repetitive DNA sequence families in Crepis capillaris

Three families of tandemly repetitive DNA from Crepis capillaris were cloned and characterized. Data obtained from in situ hybridization indicate that these families are located mainly in the heterochromatic C-bands. The pCcH32 family hybridizes at the paracentromeric C-band of the NOR (nucleolus-organized region) chromosome and along most of the long arm of the same chromosome. The pCcD29 family is located in all the remaining C-bands of the karyotype, while the third family, pCcE9, is restricted to the more proximal C-bands. Nucleotide sequence comparisons between one cloned repeating unit from each DNA family showed some significant regions of homology between the families. We discuss the sequence relationships between the three DNA families and the significance of our data in relation to models of heterochromatin evolution, emphasizing the concepts of equilocality and the differentiation of the NOR-bearing chromosome. We also examine the possible role that chromosome disposition, in either mitotic or meiotic nuclei, plays in the distribution and homogenization of heterochromatic DNA sequences.     

石貂的染色体研究

本文对分布在我国的石貂北方亚种染色体进行了较详细的研究。结果表明２ｎ＝３８,核型为１４（Ｍ）＋４（ＳＭ）＋１８（ＳＴ）,ＸＹ（Ｍ,Ａ）。Ｃ－带显示该亚种的一些染色体着丝粒区域结构异染色质弱化或消失。Ｎｏ,９染色体的短臂完全异染色质化;Ｘ染色体长臂丰出现插入杂色质带;Ｙ为完全结构异染色质组成。     

中国水仙的核型分析和小孢子发生中的细胞学研究

中国水仙(Narcissustazettavar.chinensis)只开花不结实,以鳞茎营养繁殖。对中国水仙的染色体倍性有不同的报道。对中国水仙的核型分析,支持它是三倍体的观点,但其核型也显示出了异源三倍体的倾向。在小孢子母细胞减数分裂过程中,染色体的异常行为多表现为:中期出现单个染色体游离在纺锤体外面、在后期出现的染色体桥和落后染色体、在末期出现的单个染色体游离在细胞核外形成微核的现象。这些异常现象引起小孢子的败育,也支持中国水仙为三倍体植物的观点。     

三种姬鼠的染色体比较研究

本文采用染色体分带技术（Ｇ－,Ｃ－带和银染色）,对中华姬鼠（Ａｐｏｄｅｍｕｓｄｒａｃｏ）、大林姬鼠（Ａ．ｐｅｎｉｎｓｕｌａｅ）和大耳姬鼠（Ａ．ｌａｔｒｏｎｕｍ）的核型进行了观察分析。结果表明：３种姬鼠的２ｎ均为４８。中华姬鼠的染色体均为端着丝点染色体。大林姬鼠的常规核型中,除１对中着丝点染色体（Ｎｏ．２３）外,其余均为端着丝点染色体。大耳姬鼠的核型中,有１３对端着丝点染色体,２对亚端着丝点染色体,１对亚中着丝点染色体和７对中着丝点染色体。中华姬鼠Ｃ－带核型中,所有染色体着丝点Ｃ－带都呈强阳性,异染色质非常丰富,Ｙ染色体整条深染。在大林姬鼠Ｃ－带核型中,Ｎｏｓ．７,１１,１５,２１,２２着丝点Ｃ－带弱化甚至近阴性,其余染色体着丝点异染色质Ｃ－带都呈现程度不同的阳性。且Ｎｏｓ．２,４,７有强弱不同的端位异染色质带。Ｘ染色体着丝点区有大块的异染色质斑带出现,Ｙ染色体整条深染。大耳姬鼠除Ｎｏｓ．３,４,１０,１２,１３染色体着丝点Ｃ－带很弱外,其余染色体着丝点Ｃ－带均呈阳性,并有８对（Ｎｏｓ．１６－２３）染色体出现异染色质短臂。从总体上看,大林姬鼠和大耳姬鼠的着丝点异染色质明显比中华姬鼠的少。中华姬鼠的Ａｇ－ＮＯＲ     

The karyotype,including G- and C-banding patterns,of the pigmy hog Sus (Porcula) salvanius (Suidae,Mammalia)

The diploid chromosome number in the pigmy hog Sus (Porcula) salvanius is 38, the karyotype looking almost identical to that of the domestic pig (S. scrofa) and those wild pigs (S. scrofa) with 2n=38 chromosomes. However, the telocentric chromosomes of the pigmy hog have one or more extra G-bands at, or close to the centromere, and C-bands which are larger than the C-bands in the corresponding chromosomes of the domestic pig.It is argued that the basic chromosome number in the genus Sus is 38 rather than 36. The cytogenetic data are discussed in relation to the taxonomy of the pigmy hog.