激素对樱桃番茄两种外植体诱导再生植株的影响

以 MS为基本培养基 ,附加不同浓度的 6-BA、IAA和 NAA培养樱桃番茄两种外植体以诱导再生植株。结果表明 :含 NAA的 MS+6-BA2 mg/L(单位下同 ) +NAA0 .2培养基诱导的叶片愈伤组织 ,经继续培养无芽的分化 ,含 IAA的 MS+6-BA2 +IAA0 .2培养基诱导的愈伤组织 ,经继续培养诱导芽的分化 ;含 NAA或IAA的 MS+6-BA2 +NAA0 .2和 MS+6-BA2 +IAA0 .2培养基利于下胚轴愈伤组织的诱导 ,而不含生长素的 MS+6-BA1 .0培养基可直接诱导芽的分化。     

费尔干猪毛菜愈伤组织的诱导、分化及植株再生体系的建立

探讨了植物生长调节剂、外植体等因子对费尔干猪毛菜（Salsola fergartica Drob．）愈伤组织诱导、分化与植株再生的影响。结果表明：2,4-D与6-BA组合使用时,在一定浓度范围内均有愈伤组织产生,最佳的诱导培养基为MS＋2,4-D2．0mg／L＋6-BA0．2mg／L,下胚轴为诱导愈伤组织的最佳材料;愈伤组织继代培养较好的培养基为MS＋NAA0．1mg／L＋6-BA1．0mg／L;愈伤组织不定芽分化培养基为MS＋6-BA0．5mg／L＋NAA0．05mg／L;根分化的培养基为1／2MS＋IBA0．2mg／L,且生根率可达72％。以带柄子叶为外植体,诱导丛生芽的最佳分化培养基为MS＋6-BA1．0mg／L,再生频率可达90．74％。     

植物生长物质对大花红景天愈伤组织诱导及苗再生的影响

以大花红景天植物的茎、叶、芽、种子为材料,采用DPS软件正交设计法,通过添加不同植物生长物质,考察其对大花红景天愈伤组织形成及苗再生的影响,为低海拔条件下建立大花红景天植株再生体系提供数据基础。结果表明：种子和芽是诱导愈伤组织最适宜的外植体;植物生长物质对愈伤组织形成的影响大小为6-BA〉KT〉2,4-D〉NAA〉IAA,愈伤组织形成的最佳培养基为MS＋6-BA 4.0 mg.L-1＋KT 0.1 mg.L-1＋NAA 0.1 mg.L-1＋IAA 0.2 mg.L-1;不定芽分化的最佳培养基为MS＋TDZ 0.5 mg.L-1＋NAA 0.5 mg.L-1,诱导率达63.14%,不定芽数平均为11.4。本试验获得的最佳培养基配方,适宜在低海拔条件下进行快速诱导大花红景天的愈伤组织和植株再生。     

香蕉草叶柄离体培养与快速繁殖(简报)

以香蕉草叶柄为外植体进行离体培养及快速繁殖条件研究。结果表明,叶柄外植体在培养基MS＋6-BA 2．0mg／L＋NAA 0．3mg／L＋蔗糖30g／L＋卡拉胶7g／L上诱导形成愈伤组织后,转入分化培养基MS＋KT 1．0mg/L＋NAA0．2mg/L可诱导不定芽分化;不定芽转入增殖培养基MS＋6-BA 1.0mg/L＋NAA 0．5mg／L可旺盛增殖,增殖系数4．5。不定根分化培养基为MS＋IBA 0．2mg／L＋NAA 0．05mg／L,生根苗在水族箱移栽成活率达98％。     

黄山药愈伤组织诱导与分化

采用黄山药野生植株作为外植体,试验了不同激素处理对黄山药愈伤组织的诱导、分化影响,结果表明：不同的外植体的诱导率差别较大,叶片的诱导率最高,最高达到85．7％,茎段的诱导率较低,平均诱导率仅10％左右。以叶片作为外植体诱导愈伤组织的最佳培养基配方为MS 2,4-D2．0mg／L 6-BA2．5mg／L;愈伤组织分化生芽的最佳配方为MS BA1．0mg／L NAA0．5mg／L 蔗糖2％ pH6．4;愈伤组织分化生根的最佳配方诱MS BA1．0mg／L NAA0．1mg／L 蔗糖3％ pH6．80。     

叶子花的组织培养与微繁技术研究

叶子花茎尖、茎段接种在MS附加不同浓度组合的6-BA、IAA、IBA、NAA培养基上可诱导茎尖及腋芽的生长而获得无性系芽,无性系芽茎尖和茎段在MS附加6-BA0．5mg／L,NAA0．05mg／L进行继代培养,一般不形成丛生芽,以茎尖生长和腋芽萌生增殖,增殖系数为2．73;高度大于3cm的增殖芽在1／2 MS附加IAA lmg／L、IBA lmg／L、NAA0．2mg／L培养基上生根率为80．5％,生根苗用“二步法”移栽成活率在97％以上。无性系芽的幼叶、茎段在MS附加6-BA和NAA、2,4-D培养基上能高频产生愈伤组织,但愈伤组织在所试验的所有培养基上均无不定芽或胚状体的分化。     

樱桃砧木Colt离体叶片再生

以樱桃砧木Colt试管苗的叶片为外植体,通过先诱导愈伤组织分不定芽以及叶片直接分化不定芽两种途径诱导再生,结果表明,在MS附NAA1．0mg/L、KT3．0mg/L、ZT0．25mg/L培养基中,愈伤诱导率可达100％;诱导的愈伤MS附加NAA0．2mg/L、IAA0．5mg/L、6－BA0．5mg/L、KT1．0mg/L,GA0．5mg/L培养基中,不定芽分化率为21．3％,在MS附加6-BA6．0mg/L、NAA1．0mg/L、GA0．5mg/L中,叶片一叶柄不定芽诱导率可达48．3％。     

贯叶金丝桃组织培养的研究

分别以甘肃天水贯叶金丝桃的幼根、幼茎、幼叶为外植体．在1／2MS培养基上附加各类激素,进行贯叶金丝桃的组培实验。研究发现各外植体的增殖速率由高到低分别为幼茎、幼根、幼叶,且得到贯叶金丝桃组培各阶段的最佳培养基成分。诱导愈伤组织的培养基为1／2MS 1．3～1．6mg／L BA 0．2mg／L NAA;培养基1／2MS 1．3～1．6mg／L BA 0．15mg／L NAA有利于不定芽的形成;诱导不定根的培养基为l／2MS IBA0．5～O．8mg／L 蔗糖2．0％。向1／2MS培养基中添加不同的生长素(IAA,IBA,NAA,2．4-D)．在不同浓度梯度的培养基上进行诱导贯叶金丝桃的愈伤组织及不定根的试验,结果表明：生长素IAA,IBA既可诱导愈伤组织,又可以诱导不定根的产生。生长素NAA,2,4-D可诱导产生愈伤组织,但对不定根的诱导作用较差。     

黄芩愈伤组织诱导研究(简报)

以黄芩带节茎段为外植体,在含6-BA1．0mg／L和NAA0．2mg／L的MS培养基上培养,可直接分化出芽,分化芽的茎段在相同培养基及培养条件下能够诱导形成愈伤组织。     

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。     

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.