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1.
贻贝核型及染色体带型分析   总被引:18,自引:0,他引:18  
王琼  童裳亮 《动物学报》1994,40(3):309-316
本文对贻贝染色体进行了核型分析,其结果为:2n=28,12m+10sm+6st,NF=50,TCL=103.90μm,CL:2.735-4.774μm。第1、2、4、8、11、12对为中部着丝粒染色体(sm),第3、5、7对亚端部着丝粒染色体(sm)。对贻贝染色体的G带,C带、银染色带进行了分析。银染结果表明,贻贝细胞中有四个银染核仁组织区,分布在第3、5对染色体长臂末端。  相似文献   

2.
胡边  孙金海 《遗传》1999,21(5):27-30
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  相似文献   

3.
五种珍珠菜的核型研究   总被引:6,自引:2,他引:4  
本文对5种珍珠菜亚属植物进行了染色体数目及核型研究。其中瓣珍珠菜2n=24=12m+8sm+4st(2SAT)、黑腺珍珠菜2n=22=2m+4sm+6st+10t、泽珍珠菜2n=24=14m+6sm(2SAT)+4st和小叶珍珠菜2n=48=34m+10sm+4st的染色体数目及核型为首次报道。中国九江产的红根草核型2n=24=20m+4sm(2SAT)与日本产的核型2n=24=18m(1SAT)  相似文献   

4.
大仓鼠的核型与B染色体研究   总被引:1,自引:0,他引:1  
采用骨髓细胞染色体制片法,对分布于山东济南、泰山、东北长白山和陕西西安的大仓鼠的染色体组型、G-带、C-带和银染核型进行了分析研究。济南、西安和长白山的标本的二倍体数目和核型相似,2n=28,22t+4m+XY(st,m)。泰山标本的二倍体数目为2n=28~29,即在675%的中期相中多出了一条形态最小的端着丝粒染色体,这条染色体为B染色体,可能起源于X染色体。泰山标本的A染色体组与上述3地标本相同。4地标本的G-带、C-带和银染核型相似。除B染色体外,每个端着丝粒染色体都具有着丝粒异染色质,AgNORs较恒定地出现在Nos2,4,8,9,13染色体上。也就是说大仓鼠的B染色体为C-带阴性,不携带核仁组织者。这种B染色体C-带阴性的特征在赤狐、黑家鼠和大林姬鼠朝鲜亚种中亦有报道。  相似文献   

5.
湖南6种毛莨科植物的核型研究   总被引:6,自引:0,他引:6  
杨亲二  罗毅波  洪德元   《广西植物》1994,14(1):27-36+99
本文对产于湖南的6种毛莨科植物的染色体进行了研究。裂叶星果草[Asteropyrumcavaleriei(Levl.etVant)Drumm.etHutch.)的染色体属于R型,核型公式为2n=16=12m+2sm+2t,核型类型属于ZB;打破碗花花(AnemonehupehnsisLem.)的核型公式为2n=16=10m+4st+2t(2sat),核型类型属于2A;粗齿铁线莲[Clematisapiifoliavar.argentilucida(Levl.etVant)W.T.Wang]的核型公式为2n=16=10m+2st+4t(2sat)或2n=16=10m+2st+4t(4sat)随体染色体数目在居群之间有变化,核型类型属于2A;扬子铁线莲[Clematisganipiniana(Levl.etVant)Tamura]的核型公式为2n=16=10m+2st+4t(4sat),核型类型属于2B;毛莨(RanunculuscantoniensisDC.)的核型公式为2n=16=6m+4st+6st(2sat),核型类型属于3A;毛莨(RanunculusjaponicusThunb.)的核型公式为2n=?  相似文献   

6.
落叶松属的核型及系统位置的研究   总被引:6,自引:1,他引:5  
本文分析了我国特产树种红杉Larix potaninii的核型,K(2n)=24=12m+8sm+4st,属2A类型,染色体相对长度组成为2n=24=4L+8M2+8M1+4S。落叶松属植物(10种)的核型由6对较长的中部着丝粒染色体和6对较短的,臂比大于2的近中或近端着丝粒染色体构成,这是较为进化的核型,其中红杉组Sect.Multiserales则似有比落叶公组Sect.Larix更进化的趋势  相似文献   

7.
泉水唇鱼的核型和带型研究   总被引:2,自引:0,他引:2  
本文用上皮细胞培养方法对金沙江水系的泉水唇鱼染色体进行了研究。其二倍体数2n=50,核型组成为16m+20sm+14st,NF=86。阳性C=带位置有几种类型(1)着丝粒区;(2)短臂异染色质化;(3)插入异染色质带。Ag-NORs有7条,出现在Nos.10-13染色体短臂。根据以上所述特征,推浊泉水唇鱼可能是较为特化的种类。  相似文献   

8.
国产沙参属五个种的核型研究   总被引:1,自引:1,他引:0  
首次报道了5种国产沙参属(Adenophora)植物的染色体数目和核型。北方沙参A.borealisHongetY.Z.Zhao的核型公式为2n=34=28m+4sm(2sat)+2st(2sat);雾灵沙参A.wulingshanicaHong的核型公式为2n=34=26m(4sat)+6sm+2st或2n=34+1B=26m(4sat)+6sm+2st+1B;秦岭沙参A.petiolataPaxetHofm.的核型公式为2n=34=26m(2sat)+6sm+2st或2n=34+1B=26m(2sat)+6sm+2st+1B;裂叶沙参A.lobophylaHong的核型公式为2n=34=26m+4sm(2sat)+4st或2n=34+2B=26m+4sm(2sat)+4st+2B。泡沙参A.potaniniKorsh的核型公式为2n=34=28m(2sat)+4sm+2st。它们同以往报道的其它种的核型相似:以中部着丝点染色体(m)为主,至少具一对近端着丝点染色体(st)和一对随体染色体,核型的对称程度较高,着丝点端化值(T.C)为58.4%~62.0%。结合其它性状,讨论了裂叶沙参的特殊性  相似文献   

9.
中国四种龟的细胞遗传研究   总被引:13,自引:0,他引:13  
本文研究了我国四种龟类动物的核型、C带和Ag-NOR_s。结果表明金头闭壳龟的核型2n=52(14M+2SM+4ST+6T+26m),NF=72,核型模式为8+5+13,一对次缢痕位于I组的No.1pinter;三线闭壳龟核型2n=52(12M+4SM+4ST+6T+26m),NF=72,8+5+3,黄缘盒龟的核型 2n=52(16M+4ST+6T+26m),NF=72,8+5+13,一对次缢痕位于I组No.1pinter;黄额盒龟2n=52(16M+2SM+4ST+6T+24m),NP=74,9+5+12,有4对次缢痕,分别位于I组的No.1pinter,No.3pper,No.7pper和No.6(X染色体)qper。黄额盒龟有1对异型(XY型)性染色体,其余3个种没有。这四种龟的全部染色体都出现着丝粒区C带正染。它们都仅出现1对AgNORs,其中黄额盒龟的Ag-NORs。位于II组的No.5qper,其余3个种的Ag-NOR_s位于I组的No.7qter。本文还阐述了近缘种间核型的演化机制和黄额盒龟性染色体分化的途径。  相似文献   

10.
安徽黄精属的细胞分类学研究   总被引:10,自引:3,他引:7  
邵建章  张定成  钱枫   《广西植物》1994,14(4):361-368
本文首次报道黄精属PolygonatumMill我国三种特有植物的染色体数目和核型,结果如下:安徽黄精P.anhuiense发现两个细胞型:(1)2n=24=4m+6sm+14st;(2)2n=20=4m十6sm+10st;  黄精P.langyaensy2n=18=6m+8sm+4t;距药黄精P.franchetii有三个细胞型:(1)2n=22=8m+8sm(2sc)+6st;(2)2n=20=2m+14sm+4st;(3)2n=18=4m+8sm+4st+2T,全部属3B核型。黄精属植物安徽共有10种,本文对9种黄精的染色体数目、核型进行了比较研究,发现它们可划分成三个类群,与中国植物志(第十五卷)的形态分类基本相符。  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

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Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

18.
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

19.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细  相似文献   

20.
For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

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