SSR分子标记在烟草研究中的应用进展

SSR分子标记技术作为最常用的分子标记技术之一,该标记技术重复性好,结果可靠,近年来在烟草遗传育种中展示了广阔的应用前景,是应用潜力较大的分子标记技术。介绍了SSR分子标记的原理及其分布特征,对其在烟草基因定位及分子标记辅助选择、种质资源研究、遗传图谱构建及种子纯度及真伪鉴定研究中的应用等方面进行了综述,并探讨了SSR分子标记技术在烟草遗传育种中的应用前景,以期为烟草SSR分子标记技术的研究提供参考。     

黄瓜分子标记辅助育种研究进展

本文综述了不同分子标记技术在黄瓜遗传连锁图谱构建、重要性状相关基因的定位、种质资源遗传多样性分析和亲缘关系鉴定、分子标记辅助选择、种子纯度与活力鉴定及其在黄瓜遗传育种等方面的应用,讨论了目前黄瓜遗传育种中应用分子标记技术存在的问题和今后育种工作的重点,并对黄瓜分子标记辅助育种的前景作了展望。     

分子标记技术在烟草种质资源研究中的应用进展

DNA分子标记作为新发展起来的一种遗传标记形式,凭借其可靠有效等优点,在农业科学研究中的应用越来越广泛。综述了几种分子标记技术(RAPD、AFLP、ISSR)在烟草种资源中的应用进展,分析了分子标记技术在烟草种资源及遗传多样性研究中存在的问题及今后发展方向。     

分子标记技术在烟草种质遗传多样性研究中的应用进展

DNA分子标记作为新发展起来的一种遗传标记形式,凭借其可靠有效等优点,在农业科学研究中的应用越来越广泛.综述了几种分子标记技术(RAPD、AFLP、ISSR)在烟草种质资源中的应用进展,分析了分子标记技术在烟草种质资源及遗传多样性研究中存在的问题及今后发展方向.     

分子标记技术及其在植物遗传育种中的应用

本对遗传标记技术的发展历程作了简要的回顾。概述了目前常用的RFLP和RAPD等分子标记技术的基本原理和特点,及其在构建分子遗传图谱、品种间遗传关系分析、进行基因定位和测定遗传距离等遗传育种中的应用。     

葫芦科瓜类作物分子标记辅助育种研究进展

综述了几种常用分子标记在葫芦科瓜类作物遗传图谱构建、重要性状基因定位、遗传多样性及亲缘关系分析、分子标记辅助选择及在葫芦科遗传育种中的应用,对目前葫芦科遗传育种中应用分子标记技术存在的问题和解决方案进行了探讨,并对葫芦科分子标记辅助育种的前景做了展望。     

SSR分子标记在棉花遗传育种中的应用分析

SSR是一种新型分子标记技术,这项技术具有操作简便、稳定可靠、高度多态、保守性等特点。正是因为它具有传统标记技术没有的优势,因而能够被广泛应用于生物研究领域中,它在棉花遗传育种中的应用就是一个典型例子。本文将重点探讨SSR分子标记技术在棉花遗传育种中的应用。     

国内外苜蓿育种中的分子标记技术

概述了分子标记技术在苜蓿系统发育、种质资源、遗传育种以及根瘤菌的特异性等方面的国内外研究进展,简述了几种分子标记技术在苜蓿各研究领域的作用和贡献,并展望了分子标记技术在中国苜蓿研究中的广泛应用前景。     

分子标记及其在植物遗传育种中的应用

遗传标记可以说是生物群体中可识别的遗传多态性的一种表现形式。随着遗传研究特别是遗传作图的不断深入,遗传标记已从传统的以等位基因的表型识别为基础的形态标记、以染色体的结构和数目为特征的细胞学标记,及具有组织、发育及物种特异性的同工酶标记,拓展到目前已广泛应用的以ＤＮＡ多态性为基础的分子标记技术。现代分子标记技术的出现和发展为植物遗传育种研究的许多领域注入了新的活力。本文着重就目前植物遗传育种中所应用的一些主要分子标记技术及其应用作一概述。１　常用的分子标记技术自８０年代初有人提出用ＲＦＬＰ作为遗传…     

AFLP技术的改进及其在热带作物遗传育种中的应用

AFLP分子标记是一种基于PCR的DNA指纹分析方法,广泛应用于遗传多样性和亲缘关系的分析、遗传图谱构建、品种鉴定及标记辅助育种等方面。简要介绍了AFLP分子标记技术的原理、发展及在热带作物遗传育种中的应用。     

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.