水痘-带状疱疹病毒地方分离株在兔脑神经细胞中的形态与形态发生特征

为阐明水痘-带状疱疹病毒济南分离株（VZVJ1）在兔脑神经细胞（RNC）中的形态与形态发生特征,我们利用超薄切片电子显微镜技术对感染VZVJ1的RNC进行了观察研究。结果表明RNC在感染VZVJI6h后核内可见散在的核衣壳,12h后细胞核和细胞质内核衣壳明显增多,24h达高峰,而细胞核和细胞质内的成熟病毒颗粒较少见。病毒大小、形态基本一致,呈圆形或椭圆形,核心直径30～50nm,核衣壳74～96nm,成熟病毒110～180nm。核衣壳内有3种类型的核心,即电子致密核心、部分致密核心和电子透明核心。细胞核和细胞质内均可见核心样电子致密体和布纹样结构。在细胞质内还可见少量“繁殖复合体”,由膜性结构包绕多个囊泡构成。提示VZVJ1在RNC中的形态发生不同于其它性质的细胞。     

水痘—带状疱疹病毒分离株核衣壳的形态特征

本文用超萍切片电镜技术对水痘－带状疱疹病毒（VZV）分离株J1的核衣壳进行了形态学研究。结果表明,在病毒感染后5小时即可观察到细胞核内大量的病毒核心相关颗粒和少量核衣壳。在细胞核内和细胞浆内均可见到病毒基质或毒浆结构。VZVJ1株具有三种类型的核衣壳,命名为A型、B型、C型核衣壳。A型具有电子致密核心,B型的核心呈颗粒状,C型具有电子透明核心。三种核衣壳大小一致,直径75－100nm,核心为35－55nm。将VZV的核衣壳与疱疹病毒科其它成员作了比较分析,并对各种核衣壳在病毒成熟过程中的作用进行了探讨。     

水痘一带状疱疹病毒分离株核衣壳的形态特征

本文用超薄切片电镜技术对水痘一带状疱疹病毒(VZV)分离株J_1的核衣壳进行了形态学研究。结果表明,在病毒感染后5小时即可观察到细胞核内大量的病毒核心相关颗粒和少量核衣壳。在细胞核内和细胞浆内均可见到病毒基质或毒浆结构。VZVJ_1株具有三种类型的核衣壳,命名为A型、B型、C型核衣壳。A型具有电子致密核心,B型的核心呈颗粒状,C型具有电子透明核心。三种核衣壳大小一致,直径75—100nm,核心为35—55nm。将VZV的核衣壳与疱疹病毒科其它成员作了比较分析,并对各种核衣壳在病毒成熟过程中的作用进行了探讨。     

犬传染性肝炎病毒在体外细胞质内的发生

通过对犬传染性肝炎病毒（ＩＣＨＶ）在犬肾传代细胞内形态发生及其抗原定位的电镜和免疫胶体金电镜研究,发现ＩＣＨＶ除了在宿主细胞核内发生外,还有一条细胞质内的发生途径。在细胞质内病毒核壳体的装配是以均质致密包涵体和副晶格包涵体为“基地”,这与人们熟知的细胞核内形态发生方式相似。免疫胶体金标记显示,细胞质包涵体中含有大量的ＩＣＨＶ抗原成分,显核壳体在细胞质内装配病毒的结构蛋白来源。此外,在感染的细胞质内还观察到与核内相同的病毒核心样结构。     

人巨细胞病毒在SL_7细胞中的形态发生

人巨细胞病毒(HCMV)AD_(169)株接种SL_7细胞后三至四天,可见核衣壳在核内装配,通过核膜芽生,从核周间隙移行至胞浆的囊泡中,形成完整的病毒。感染后四天核内可见许多核衣壳与纽网状物紧密结合形成典型的包含体,因此包含体可能是病毒复制的场所。此时浆内出现电子密度均一的物质,称CMV致密体。免疫电镜显示致密体缺乏核衣壳,但具有病毒相同的抗原性。它可能是装配和包裹核衣壳的结构蛋白。CMV和致密体在感染细胞中以同一方式从细胞中释放。     

牛传染性鼻气管炎病毒的形态结构及其在细胞内发生的研究

用负染法和超薄切片法研究了我国首次分离的IBR病毒的形态结构及其在犊牛肾细胞内发育的基本过程。病毒直径为1 60--230nm,成熟病毒由直径为50—60nm的核心、直径为100—110nm的衣壳和囊膜三部分构成。在负染的样品中,可以观察到呈三重对称和二重对称的核壳体及其衣粒的构型,从而推算出病毒衣壳由162个农粒构成。该病毒具有典型疱疹病毒科的发育与成熟方式。此外,它可能与鸭瘟病毒一样,还具有一条细胞质内的发生途径。     

大菜粉蝶颗粒体病毒的形态发生及细胞病理的超微结构观察

本文叙述感染大菜粉蝶颗粒体病毒后,病虫脂肪体细胞超微结构的改变,大菜粉蝶感染后24小时,病虫脂肪体细胞开始出现明显的病变,整个病程是,在开始时细胞核内出现清晰区并出现病毒发生基质,核膜多点成套增生,其后核膜断裂,大量膜样结构聚集在病毒发生基质的周围,核衣壳大量产生,有一部分核衣壳从这些病毒发生基质四周的膜样结构碎片上获得套膜,荚膜蛋白沉积形成成熟的病毒荚膜,或称包含体;另一部分则排列在胞浆内的空泡边缘上;其余的核衣壳则从细胞边缘“芽突”而获得套膜,另外还描述环孔片层及线粒体改变。     

鸭病毒性肠炎病毒强毒株的形态发生学与超微病理学研究

应用透射电镜和超薄切片技术,研究鸭病毒性肠炎病毒(duck enteritis virus,DEV)CH强毒株人工感染成年鸭后,病毒在宿主细胞内的形态发生及各组织器官的超微结构变化.结果表明,感染后不同时间剖杀及发病后死亡鸭的肝、肠、脾、胸腺、法氏囊等组织器官中,均观察到典型的疱疹病毒粒子.病毒主要的靶细胞为淋巴细胞、网状内皮细胞、成纤维细胞、巨噬细胞、血管内皮细胞、肠道上皮细胞、肠道平滑肌细胞和肝细胞等.DEV的核衣壳有空心型、致密核心型、双环型和内壁附有颗粒型四种形态,存在胞核和胞浆两种装配方式.病毒核衣壳可在核内获得皮层,通过核内膜获得囊膜成为成熟病毒;也可通过内外核膜进入胞浆,在其中获得皮层,然后在各种质膜上获得囊膜,最后成熟病毒释放到细胞外.伴随着病毒的复制、装配和成熟,细胞中出现多种核内和胞浆包涵体、核内致密病毒核酸颗粒、微管和中空短管以及胞浆内膜包裹的电子致密小体、双层管等病毒相关结构.超微研究表明,组织细胞有坏死和凋亡两种变化.坏死细胞肿胀甚至破裂,线粒体肿胀空泡化,粗面内质网扩张,核糖体脱落,有的细胞器甚至完全崩解,染色质或固缩或溶解.凋亡细胞则染色质聚集,胞浆凝聚深染,细胞膜上有大量空泡,并有凋亡小体形成.细胞坏死与凋亡往往同时存在,疾病发生过程中,脾、胸腺、法氏囊以及小肠固有层中的淋巴细胞凋亡数量明显增多.     

鸭肠炎病毒CHv强毒株超微结构研究

将鸭成纤维细胞培养的鸭肠炎病毒(DEV),经超声处理、高速冷冻差速离心后,采用酒石酸钾—甘油非线性密度梯度超速离心,收集病毒蛋白带,3%磷钨酸负染后观察病毒粒子形态。结果表明:病毒粒子主要集中在40%~50%酒石酸钾—甘油缓冲液交界层。电镜下,病毒粒子纯净,具有疱疹病毒典型形态结构,剖面六角,外观轮廓清楚。成熟病毒粒子直径约150~266nm,病毒囊膜、核衣壳和核心清晰可见;囊膜外层较内层着色略深,且可见尚未形成完整囊膜的柄状拖尾结构。多数病毒粒子以单核衣壳为主,一定数量的病毒具有双核衣壳,偶见三核衣壳,核衣壳直径为100~150nm,呈现致密圆形、半圆形或马蹄形等类型。在核衣壳外和囊膜之间可见明显的亮晕。核心DNA电子染色较深,集中分布,直径40~65nm。本文获得的清晰DEV负染超微结构照片,为该病毒结构生物学的研究提供了重要依据。     

荨麻蛱蝶核型多角体病毒在病虫脂肪体中的形态发生

本文叙述了一种在高山草原地区较低温度下感染荨麻蛱蝶(Vanessa urticae)的核型多角体病毒的形态发生过程。荨麻蛱蝶幼虫经其病毒多角体感染5日后出现明显变化:细胞核膨大,核仁消失,核内出现清晰区及病毒发生基质。在病毒发生基质的周围,核衣壳大量产生。核衣壳是从这些病毒发生基质四周的模样结构碎片上获得套膜,装配成病毒粒子。随后病毒粒子逐渐进入多角体蛋白中,形成了成熟的单粒包埋型的多角体。观察结果表明,在较低温度下生长的荨麻蛱蝶NPV与在常温下生长的其它NPV有着类似的形态发生过程。     

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.