长江流域若干水体寡毛类区系组成及相似性分析

研究了长江流域十余个水体水栖寡毛类的区系组成及分布。共鉴定水栖寡毛类53种,隶3科27属,其中仙女虫科15属31种(占58.49%);颤蚓科11属20种(占37.74%);线蚓科1属2种(占3.77%).在河流、草型湖泊和藻型湖泊这三类水体中,以草型湖泊的物种数最多,达36种;其次为长江干流,34种;藻型湖泊仅24种。对寡毛类的种间关系及不同生境寡毛类种类组成的相似性进行了聚类分析,结果表明,寡毛类的种类分布具有明显的地域性,据此可将其划分为6类(A-F组).       

徐州城市河流和湖泊的大型底栖动物群落结构及影响因子分析

对徐州市京杭运河市区段和市区湖泊云龙湖进行了大型底栖动物群落结构及影响因子的比较研究。结果显示:城市河流和湖泊生态系统中, 大型底栖动物种类较少、群落结构相对简单, 其中城市河流大型底栖动物的组成主要为水栖寡毛类和软体动物, 城市湖泊大型底栖动物主要组成为水栖寡毛类和摇蚊幼虫。除Margalef 物种丰富度指数外, 河流与湖泊的其他群落指数相差不大。聚类分析将两类生态系统中的大型底栖动物群落明显分为两组。CCA 结果显示云龙湖大型底栖动物群落的主要影响因子是pH 和溶解氧, 京杭运河徐州市区段大型底栖动物群落的主要影响因子是总磷和化学需氧量。     

关于Tectidrilus achaetus和Aminiclineus zhujiangensis的中名

1985年和1991年,先后在珠江广州河段发现一种水栖寡毛类和一种纽形动物,经鉴定为新种,前者定名为Tectidrilus achaetus,后者定为 Amniclineus zhujinagensis对于它们的中文名称,Tectidrilusachaetus拟定为无毛裸蚓,而Amniclineus zhujiangensis则定为珠江河栖纽虫,由此而建立的新属Amni-     

大型底栖动物对淡水水质生物评价的研究进展

大型底栖动物作为淡水水域水质特征监测的指示生物越来越受到重视。底栖动物的采集主要分为定量和定性2种方法,利用底栖动物评价水质的生物学指标主要有三大类,分别是与群落结构和功能有关的指数、与种类耐污值有关的生物指数和与特定物种直接相关的生物指数。对水生昆虫、水生软体动物和水栖寡毛类对淡水水域的水质评价研究进行综述。     

利用三种分子标记研究缘毛类纤毛虫的系统发育地位

为了探讨缘毛类纤毛虫的系统发育地位 ,利用RAPD方法得到了 9种缘毛类纤毛虫、 1种四膜虫和1种喇叭虫的 3个随机引物的电泳带谱 ;测定了 7种缘毛类纤毛虫rRNA基因中的间隔区 1(ITS1)和小亚基核糖体核糖核酸 (SSrRNA)基因序列 ,并构建了相应的系统树。在比较和分析RAPD、ITS1和SSrRNA基因序列在缘毛类纤毛虫系统发育研究中的适用范围的基础上 ,以SSrRNA基因序列为分子标记研究了缘毛类纤毛虫系统发育地位 ,结果表明 :①缘毛亚纲是单系的 ,作为寡膜纲中一个亚纲的分类地位是合理的 ;②缘毛类纤毛虫可能是寡膜纲中较高等的一个类群。     

东江干流及其源头支流大型底栖动物群落结构特征与环境指示评价

2012 年4 月~6 月对东江干流及源头部分支流的底栖动物进行了采集,共获得底栖动物78 种,隶属于3 门7 纲48 科72 属。其中,水栖寡毛类3 科8 属12 种,软体动物12 科13 属17 种,水生昆虫9 目30 科47 属47 种,其他种类3 种。空间上来看,源头支流及上、中、下游的种类数分别为48 种、31 种、33 种和28 种。源头地区和上游以水生昆虫为主,密度百分比分别为70.2%和58.3%;下游以寡毛类为主,占62.0%。分析比较了 Shannon 多样性指数、生物指数(BI)和科级生物指数(FBI) 3种水质评价方法对东江水质的评价效果。东江干流水质总体良好,源头支流水质好于其他河段水质。但从水质生物学的角度与之前研究相比,底栖生物的群落特征变化较大,物种多样性有所下降,表明区域环境有恶化的趋势。     

中国水栖寡毛类的研究 Ⅱ.新疆的仙女虫类

本文系新疆水栖寡毛类的首次报导,记录仙女虫科(Naididae)7属20种,其中有新种1种,国内新记录5种。标本均系陈嘉佑同志所采集,特此致谢。1.盘缠毛腹虫 Chaetogaster diastrophus (Gruithuisen, 1828) Chaetogaster diastrophus, Michaelsen, 1900; 陈, 1940, 1959; Sperber, 1948, 1961; 梁, 1962;1962. 采集地布尔津额尔齐斯河(1962,Ⅸ,9);博斯腾湖(1962,Ⅸ,29)。2.郎氏毛腹虫 Chaetogaster langi Bretscher,1896 Chaetogaster langi, Michaelsen, 1900; ernosvitov, 1930;陈, 1940, 1959; Sperher, 1948, 1959, 1961;1962.     

两种缘毛类纤毛虫胞质Hsp70基因序列的克隆及其系统发育分析

克隆得到2种缘毛类纤毛虫——钟形钟虫(Vorticella campanula)和螅状独缩虫(Carchesium polypinum)的胞质Hsp70基因部分序列,长度均为438bp,编码146个氨基酸。以细菌为外类群,利用最大似然法和邻接法构建包括其他5种纤毛虫在内的共26个物种的Hsp70基因氨基酸序列系统发育树,其拓扑结构显示：V．campanula和C．polypinum聚在一起,并与另2种寡膜纲的嗜热四膜虫(Tetrahymena thermophila)及草履虫(Paramecium tetraurelia)聚为姊妹枝,提示了缘毛类纤毛虫为单系,且隶属于寡膜纲的系统发育地位。     

四川新陆栖寡毛类记述

1963年4、5月,与胡芝勋等同志去峨眉采集陆栖寡毛类。该地寡毛类曾由陈义(1931、1936、1946)和Gates(1935)作过报道。这次调查,又发现环毛属三个新种。记述于下。1.小囊环毛蚓Pheretima exilens,新种 外部特征 体长47—98毫米,宽3.0—5.0毫米,体节59—110(模式标本:68毫米,3.5毫米,97节)。1/2上叶式。背孔自12/13节间始。颜色褐色。环带腹面有刚毛(或仅ⅩⅥ节有)。     

蛭纲的系统演化

蛭类,俗称蚂蟥,是环节动物门中的一纲。这是一类高度特化的动物,其生活方式和身体构造与蚯蚓(寡毛类)和沙蚕(多毛类)等其他类环节动物有很大的不同。 蛭纲作为一个整体,是一个单源系统,因为它们都是由34个体节演变来的。那么,蛭纲又与哪一类环节动物近缘呢?不少学者认为它是由一类寡毛类适应外寄生生活方式演变而成。蛭类和寡毛类有许多共同点,例如:雌雄同体:无疣足;具有环带,环带分泌形成卵茧,卵在其中发育,并从茧内的营养液得到滋养;发育无变态,无自由生活的幼虫期以及相类似的胚胎学特征。但蛭类在向寄生生活特化的过程中,失去了蚯蚓用以运动的刚毛,而在身体两端     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

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.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

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.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

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.     

肝癌中HBV和HCV基因和抗原的分布及意义

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     

Selection with two alleles and complete dominance

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.