射干真叶、花蕾诱导愈伤组织的研究

目的:建立射干愈伤组织的诱导体系。方法:采用MS培养基为基本培养基,研究不同浓度激素配比及不同AgNO_3浓度对射干真叶、花蕾诱导愈伤组织的影响,并利用显微技术鉴定其愈伤组织类型。结果:射干无菌苗真叶愈伤组织诱导的最佳培养基为:MS+2,4-D 1. 0 mg·L~(-1)+6-BA 1. 5 mg·L~(-1)+NAA 1. 0mg·L~(-1)+AgNO_315mg·L~(-1),花蕾愈伤组织诱导的最佳培养基为:MS+2,4-D 1. 0 mg·L~(-1)+6-BA 1. 0 mg·L~(-1)+NAA 1. 0 mg·L~(-1),诱导率均高于60%,其中2,4-D对射干愈伤组织诱导至关重要,AgNO_3对射干真叶胚性愈伤组织的形成有一定的影响。结论:花蕾是射干愈伤组织诱导较理想的外植体材料,获得的高效愈伤组织诱导条件将为后续射干细胞悬浮体系的成功构建奠定基础。     

百合体细胞胚胎发生和植株再生

以切花百合(Lilium)品种‘黄天霸’(‘Manissa’)花器官为外植体诱导体细胞胚胎发生与植株再生。结果表明,不同花器官、不同激素配比对愈伤组织形成均具有显著影响。花丝为最佳外植体,激素对愈伤组织诱导的影响效应为NAA>6-BA>2,4-D,最适培养基为MS+1.0 mg.L-1NAA+0.2 mg.L-16-BA;激素诱导体细胞胚胎发生的影响效应为2,4-D>KT>6-BA,最佳培养基配方为MS+1.0 mg.L-12,4-D+0.2 mg.L-1KT+1.0 mg.L-16-BA;MS培养基添加IBA可促进体细胞胚萌发成苗,体细胞胚芽成苗的最佳培养基为MS+0.2 mg.L-16-BA+1.0 mg.L-1IBA。     

冬凌草组织培养及其愈伤组织诱导研究

实验采用L9（34）正交试验方法优化冬凌草组织培养快繁培养基,筛选冬凌草增殖、生根和愈伤组织诱导的最佳培养基配方。结果表明：不定芽诱导的最适培养基为MS＋0.2 mg/L IBA＋0.1 mg/L6-BA＋0.2 mg/L NAA;生根培养基为1/2 MS＋1 mg/L IBA＋1 g/L活性炭;以冬凌草茎段为外植体诱导愈伤最佳培养基为MS＋1.5 mg/L6-BA＋2 mg/L2,4-D。     

康乃馨茎段愈伤组织诱导及植株再生(简报)

以康乃馨无菌苗茎段为外植体,在MS 6-BA 0.5mg/L NAA0.2mg/L培养基上诱导产生愈伤组织,愈伤组织在MS 6-BA 0.5mg/L NAA 0.2mg/L培养基上诱导芽效果较好,芽苗在1/2MS NAA 0.1mg/L培养基上可诱导生根。     

金线莲外植体筛选及愈伤组织诱导研究

以金线莲茎段、叶片、茎片、不定芽为试材,分别在添加6-BA、ZT、NAA、KT 5个不同处理的MS及1/2MS培养基上培养,诱导愈伤组织。结果表明,以茎段、茎片、不定芽为外植体,在MS + 6-BA 2.0 mg/L + NAA0.5 mg/L、MS + NAA 2.0 mg/L + KT 0.1 mg/L和MS + 6-BA 2.0 mg/L + NAA 0.5 mg/L + ZT 0.2 mg/L培养基中培养,均能成功诱导愈伤组织。不定芽为诱导愈伤组织最佳外植体,最佳培养基为MS + 6-BA 2.0 mg/L + NAA 0.5 mg/L + KT 0.2 mg/L。     

水杉组织培养研究

以水杉的带腋芽茎段和茎尖为外植体进行植物组织培养,探究外植体形成无菌苗体系的过程最佳激素配比及影响因素。在MS基本培养基中添加不同激素,制备不同培养配方,筛选水杉愈伤组织诱导与分化的最适培养基配方。诱导愈伤组织形成的最佳培养基配方为MS+2,4-D (2.0 mg/L)+NAA (3.0 mg/L)+6-BA (1.5 mg/L);适宜再分化的最佳培养基为MS+NAA (0.2 mg/L)+6-BA (1.5 mg/L);最佳生根培养基组合为1/2MS+NAA (3.0 mg/L)+IBA(0.1 mg/L),生根率为18.8%以上,培养15 d后平均根数可达到45条,平均根长达2.56 cm。     

甘蓝型油菜子叶和下胚轴再生植株无性系建立

以甘蓝型油菜(Brassica napus L.)豫油2号和6257的子叶和下胚轴为材料,在不同激素配比的MS培养基上诱导出了愈伤组织。将经过继代的部分愈伤转入分化培养基,分化结果表明:除基因型、外植体和分化培养基的激素配比对分化率有影响外,诱导愈伤培养基的激素配比对分化率也至关重要。豫油2号的子叶和下胚轴在最适诱导培养基(ZT 1+NAA0.5+2,4-D 0.2 mg/L)和最适分化培养基(ZT4+IAA 0.2 mg/L)组合中的愈伤分化率分别为12.5%和75%;6257的子叶和下胚轴在其最适诱导培养基(KT 2+NAA1+2,4-D 0.2 mg/L)和最适分化培养基(6-BA 4+IAA 0.02 mg/L)组合中的愈伤分化率分别为50%和37.5%。将其最适诱导培养基中的愈伤组织继代达8个月以上,建立了不同继代愈伤的再生植株无性系。     

轮叶党参的组织培养及植株再生研究

以轮叶党参为材料,研究了不同外植体、激素组合、培养基及光照条件对愈伤组织诱导及植株再生的影响.结果表明,叶片是轮叶党参组织培养较为合适的外植体.外植体在添加0.5 mg·L~(-1) 2,4-D+1.0 mg·L~(-1) 6-BA+0.5 mg·L~(-1) KT的MS培养基上愈伤组织诱导率最高可达100%;愈伤组织转移到附加0.75 mg·L~(-1) 6-BA+0.5 mg·L~(-1) NAA的MS培养基进行继代培养,增殖后的愈伤组织转移到附加0.5 mg·L~(-1) 6-BA+0.2 mg·L~(-1) NAA的1/2MS分化培养基进行分化,其分化率达89.4%;将分化出的芽转接到附加0.2 mg·L~(-1) IAA+0.2 mg·L~(-1) NAA的1/2MS培养基,生根率达92.5%.暗培养诱导出愈伤组织后转到16 h·d~(-1)光照条件下,愈伤组织增殖倍数和分化率显著提高,再生苗健壮,长势强.     

两个薄荷品种叶片愈伤组织的诱导及增殖

采用正交实验设计,研究了诱导培养基中6-BA、NAA和VC浓度及基本培养基类型4个因素对薄荷(Mentha haplocalyx Briq. )品种'687'和'沪39'叶片愈伤组织诱导的影响, 并研究了增殖培养基中6-BA、 NAA、 IBA和 2,4-D浓度对愈伤组织增殖的影响,筛选出适宜于品种'687'和'沪39'叶片愈伤组织诱导和增殖的最适培养基.结果表明,培养基中6-BA、NAA和VC浓度及基本培养基类型对品种'687'和'沪39'叶片愈伤组织的诱导率和褐化率均有一定的影响,但不同品种适宜的培养基配比有一定的差异;NAA浓度对品种'687'愈伤组织诱导的影响作用显著,影响品种'沪39'愈伤组织诱导的主要因素是VC浓度和基本培养基类型.适宜于品种'687'叶片愈伤组织诱导的培养基为含0.5 mg·L-1 6-BA和1.5 mg·L-1 NAA的B5培养基,适宜于品种'沪39' 愈伤组织诱导的培养基为含 1.5 mg·L-1 6-BA、 1.5 mg·L-1 NAA 和 100 mg·L-1 VC 的 1/2MS 培养基, 均含 5.5 g·L-1 琼脂和 30 g·L-1蔗糖(pH 5.5～pH 5.8).2个品种叶片愈伤组织增殖所需的生长调节剂浓度及比例也有一定的差异,较高浓度的细胞分裂素有利于愈伤组织的增殖,品种'687' 和'沪39'叶片愈伤组织增殖的适宜培养基分别为B5培养基和1/2MS培养基,均含2.0 mg·L-1 6-BA和1.5 mg·L-1 NAA以及5.5 g·L-1琼脂和30 g·L-1蔗糖(pH 5.5～pH 5.8).     

枇杷叶荚蒾的愈伤组织诱导及植株再生

以枇杷叶荚蒾幼叶为外植体,MS为基本培养基,研究不同种类和浓度的植物生长调节物质对愈伤组织诱导、分化及生根的影响,建立了枇杷叶荚蒾再生体系。结果表明:枇杷叶荚蒾最佳灭菌组合为75%酒精预处理20s,再用0.1%HgC12浸泡12min;最佳愈伤组织诱导培养基为MS+6-BA1.0mg·L-1+NAA0.25mg·L-1+2,4-D1.0mg·L-1,诱导率最高达92%;最适芽分化培养基为MS+6-BA1.5mg·L-1+NAA0.2mg·L-1,分化率达87.25%;适宜的生根培养基为1/2MS+NAA1.0mg·L-1,生根率达85%。     

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.