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1.
云南四种树蛙的细胞遗传学研究(无尾目:树蛙科)   总被引:2,自引:0,他引:2  
本文报道了分布在云南的4种树蛙(峨眉泛树蛙,黑点泛树蛙,无声囊泛树蛙和棕褶树蛙)垢核型,C-带及Ag-NORs它们具有相同的二倍体数(2n=26),除无声囊泛树蛙是6+7,其余均为5+8核型模式,种间SM的数目和顺序,次缢痕和Ag-NORs相互间有所差异。黑点泛树蛙Nos.3,12为SM,Ag-NORs位于10p^finter,峨眉泛树蛙Nfos2,3,4,6.9为SM,随体和Ag-NORs在12  相似文献   

2.
中国鲌亚科-新属(鲤形目:鲤科)   总被引:1,自引:1,他引:0  
中国鲌亚科-新属(鲤形目:鲤科)罗云林(中国科学院水生物研究所,武汉430072)关键词新属,亚科ANEWGENRUOFCULTRINAEFROMCHINA(CYPRINIFORMES:CYPRINIDAE)¥LuoYunlin(InstuteofH...  相似文献   

3.
中国几种棘蛙的核型C—带和Ag—NORs研究   总被引:10,自引:0,他引:10  
本文对4种棘蛙的核型、C-带和Ag-NORs作了观察分析,结果表明无声囊棘蛙2n=64T,Ag-NORs在20q^inter,全部着丝点区域C-带正染。云南的棘腹蛙、察隅棘蛙和河南太行山隆肛蛙3者,其2n=26,5+8模式,但相互间SM的对数和顺序有所不同;前二者的Ag-NORs均在6p^per,但C-带有很大的不同:察隅棘蛙的着丝点C-带浅染,但有较多的端部和居间型C-带。隆肛蛙的Ag-NORs  相似文献   

4.
李树深  胡健生 《动物学报》1994,40(3):317-323
本文比较分析了云南景东地区三种同域分布棘蛙的核型和Ag-NORs。花棘蛙2n=26(16M+ 10SM),NF=52,次缢痕和Ag-NORs位于1pinter,Nos.2-4,8,9等为SM。棘肛蛙2n=40(16M+ 20SM+2ST+2T),NF=78,Nos.5-9,11-13,15,17等10对为SM,No.3为ST,No.18为T,其余 均为M,Ag-NORs位于11P。二种的Ag-NORs都有异形现象。双团棘胸蛙2n=64T,次缢痕和Ag- NORS在4qper。都未发现异形性染色体。最后,对棘蛙属的核型演化机制和物种形成方式作了讨论。  相似文献   

5.
达乌尔黄鼠染色体银染核仁组织者分析   总被引:2,自引:1,他引:1  
达乌尔黄鼠染色体银染核仁组织者分析ANALYSISONCHROMOSOMESAg-NORSOFCITELLUSDAURICUSKeywordsCilellusdauricus;Chromosome;Ag-NOR达乌尔黄鼠(cilellusdauric...  相似文献   

6.
沼泽绿牛蛙的核型及银染研究   总被引:3,自引:0,他引:3  
沼泽绿牛蛙的核型及银染研究樊连春,杨仲安,魏丽华,梁绍昌,桂建芳(中国科学院水生生物研究所武汉430072)关键词沼泽绿牛蛙,核型,Ag-NORsANINVESTIGATIONOFTHEKARYOTYPEANDAg-NORsOFRANAGRYLIO¥...  相似文献   

7.
中国五种锄足蟾科无尾两栖动物的细胞遗传学研究   总被引:5,自引:1,他引:4  
李树深  费梁 《动物学研究》1996,17(2):173-178
本文对中国5种锄足蟾科无尾两栖动物的骨髓细胞有丝分裂中期作了细胞遗传学研究,内容包括核型、Ag-NORs和C-带。研究结果表明景东角蟾:2n=26(20M+4SM+2ST),5+8,SC和Ag-NORs位于6p^per,同时呈C-带正染。C-带以着丝点区域正染为主;粗皮角蟾:2n=26(20M+6SM),5+8,Ag-NORs在6q^inter,以着丝点C-带为主,但Nos.12,13有明显的端位  相似文献   

8.
福建两种棘蛙的核型和Ag-NORs观察结果如下:九龙棘蛙,2n=26(22M+4SM),NF=52,5+8模式,Ag-NORs位于6pinter,小棘蛙,2n=26(20M+6SM),NF=52,5+8模式,次缢痕和Ag-NORs在6pinter。二者均未发现与性别分化相关的异形染色体。根据已知棘蛙属内的核型资料,对该属种间和居群间的核型演化机制进行了讨论。  相似文献   

9.
两种长臂猿染色体的C带和Ag-NORs的比较研究   总被引:1,自引:0,他引:1  
本文对长臂猿属(Hylobates)中白眉长臂猿(H.hoolock)2n=38和白颊长臂猿(H.leucogenys)2n=52的染色体C带和Ag-NORs进行了比较研究。结果表明,两种长臂猿的C带核型中除多数染色体有着丝点C带外,一些染色体上还出现插入C带和着丝点C带弱化或减少现象;白眉长臂猿有全异染色质臂;白颊长臂猿有较多的端位C带。白眉长臂猿有两个Ag-NORs,而白颊长臂猿的Ag-NORs雌体有4个,雄体有5个,Y染色体上有NOR.本文对长臂猿的核型进化作了讨论。  相似文献   

10.
采用核仁组成区嗜银蛋白(Ag-NOR)技术,对40例胸腹水的患者进行细胞学观察研究。结果发现,良性病变胸腹水内细胞Ag-NOR计数在1.1~2.0之间,银颗粒小,大小比较均一。恶性病变Ag-NOR计数在4.3~6.2之间,银颗粒大,不规则。肉瘤与癌所致的胸腹水内细胞Ag-NOR颗粒数目未发现有明显差别。提示在临床病理工作中,Ag-NOR技术在胸腹水脱落细胞学检查中,对良、恶性肿瘤的鉴别诊断具有一定的实用意义。  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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16.
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   

17.
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   

18.
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   

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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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