上海地区草莓病毒病病原研究初报

上海郊区草莓病毒病害表现多种症状,并日趋严重,关于草莓病毒病病原的研究,国内尚未见报道,我们将草莓病叶经氯仿和聚乙二醇处理,蔗糖梯度离心,可获得部分纯化的病毒分离物,电镜观察可见大小不同的二种球状病毒颗粒,直经分别为28—30毫微米和40毫微米左右,可能与国外报导的草莓隐潜环斑病毒(SLRV)和草莓脉暗病毒(SVBV)相似。     

植物病毒病的诊断技术

植物病毒病是一种全球性的病害,每年全世界由植物病毒病造成的农作物损失估计高达１５０亿美元。植物病毒病的准确诊断有利于病毒病的综合防治。近年来,由于植物病毒分类体系的逐步完善,以及病毒鉴定技术的不断进步,植物病毒病的诊断方法有很大发展。本文介绍植物病毒诊断技术的发展现状。１生物学鉴定 利用生物学鉴定进行植物病毒病的诊断,主要依据寄主植物和病毒的传播方式。寄主植物诊断的方法主要包括利用寄主病症、寄主范围和交叉保护现象。在早期的植物病毒研究中,病毒检测和鉴定是以病症为主要根据,现证实这不太可靠［１］,…     

草莓去病毒苗增产效益显著

草莓是营养丰富的水果,具有栽培容易、当年结果、收益产量高、价格高等优点,各地发展很快。但是草莓在生产上容易感染多种病毒病,感染了病毒病的草莓果子变小、畸形,品质差,叶子皱缩,生长缓慢,一般减产30—80％。对病毒病目前还没有药剂可以防治,近几年各地先后从日本、美国引进大果型优良品种,在生产上种植2—3年后产量明显下降,果子变小,     

植物抗病毒基因工程研究进展

病毒作为一种依赖于宿主细胞代谢的病原体对全球农业造成了重大经济损失。虽然目前已利用多种防治策略来控制病毒病,例如培育抗病毒品种、使用化学杀菌剂、切断病毒的感染途径、组织脱毒、传统农业防治等,但都无法从根本上控制病毒病的危害。近年来的研究表明,基因工程手段能够有效对抗植物病毒病害。本文综述了基因工程手段改造植物抗病毒能力的技术和方法。     

蘑菇废弃物的综合应用研究

近年来,蔬菜植物病毒病在大连市蔬菜区己成为严重危害生产的重要问题之一。迄今国内外尚无良好的防治植物病毒病农药。由于病毒对寄主细胞代谢的高度依赖特性,因而对病毒有抑制作用的药物往往对寄主产生药害,这就给筛选防治植物病毒病的药剂带来极大困难。     

棉铃虫质型多角体病毒的形成

目前已知棉铃虫病毒病共有四种类型:核型多角体病毒病,质型多角体病毒病,颗粒体病毒病和虹彩病毒病(Martignoni＆lwai 1977;Stadelbacher et al.1978)。棉铃虫的质型多角体病毒(简称CPV)常与核型多角体病毒混合发生,给寄主的正常饲养繁殖和核型多角体病毒的增殖利用带来了重大困难。此外,对这类病毒在防治棉铃虫的作用方面也需要作出正确的评价。我们曾报道过棉铃虫质型病毒的分离、特征和病理学(苏德明等,1978),本文应用电子显微镜技术研究该病毒在寄主中肠上皮细胞内的形成过程,以进一步阐明其增殖发病机理,并为其利用研究提供依据。     

矮牵牛病毒病的初步研究

矮牵牛是一种草本花卉,主要用来布置花坛,但病毒侵染却严重地影响其观赏价值。国内外有关危害矮牵牛的病毒报道较多［１,２］,但较系统研究矮牵牛病毒病的报道较少,本文从矮牵牛病毒鉴定、优势病毒种类确定及防治矮牵牛病毒病进行了初步研究,现报道如下：材料与方法...     

微生物来源的抗植物病毒活性物质研究进展

近年来,研究者利用微生物及其次生代谢产物开展了大量防治植物病毒病的研究,从中发现了许多具有抗植物病毒活性的大分子物质及小分子化合物。本文对来源于不同种类微生物的抗病毒活性物质及抗病毒机理作了论述,并对微生物来源抗植物病毒物质研究进行了展望,以期为开发用于植物病毒病防治的微生物农药提供借鉴。     

太子参花叶病毒的检测与防治

1982年我们在国内外首次发现太子参花叶病毒,并对该病毒的形态结构、症状表现、宿主范围、血清学、生化特性等进行了研究,同时还对太子参病毒病进行了初步防治。在上述工作的基础上,我们又进一步应用ELISA技术,对太子参花叶病毒进行了田间检测,并确认了种子消毒方法,为太子参花叶病毒病的田间诊断与防治提出了科学措施。     

一种牛干扰素研制成功

干扰素是一种稀缺的药物,用它有效地防治病毒病。美国遗传工程公司应用基因捻接技术研制牛干扰素已获得成功。家畜中流行的一种病叫出血性败血病(Shipping fever),由一种病毒引起的。     

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.