新疆雪莲愈伤组织诱导及总黄酮的测定

以新疆雪莲植株叶片为外植体,研究了不同植物激素和培养时间对新疆雪莲愈伤组织生长、总黄酮含量和产量的影响.结果表明:新疆雪莲愈伤组织最佳诱导培养基为MS+2.00 mg/L NAA+1.00 mg/L 6-BA,其愈伤组织诱导率最高(97.0%);继代培养基以MS+2.00 mg/L NAA+1.00 mg/L 6-BA中愈伤组织生长量和总黄酮产量最高,分别达4.58 g和12.24 mg;以MS+4.00 mg/L NAA+2.00 mg/L 6-BA中的愈伤组织总黄酮含量最高,达2.17 mg/g;愈伤组织的生长量随继代培养时间的延长而增加,而其总黄酮含量不稳定,于继代培养第30天达到最高(2.7 mg/g),此时总黄酮产量最高可达26.66 mg.     

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。     

不同产地、不同物候期对乌腺金丝桃中总黄酮含量的影响

目的:探讨不同产地、不同物候期乌腺金丝桃中总黄酮含量的变化。方法:采用比色法测定了3个产地乌腺金丝桃在不同物候期总黄酮的含量。以总黄酮为技术指标筛选乌腺金丝桃药材的采收期、黄酮含量最高的产地。结果:以总黄酮成分为指标确定的产地、采收期为:佳木斯猴石山产,花盛期采收。结论:通过研究发现乌腺金丝桃药材以勃利县产花盛期采收总黄酮含量最高,对乌腺金丝桃的开发有一定指导意义。     

白刺花胚性愈伤组织诱导及体细胞胚发生和萌发

探讨不同因素对白刺花下胚轴、子叶2种外植体胚性愈伤组织诱导及体细胞胚发生和萌发的影响。以B5和MS为基本培养基,研究2,4-D、6-BA和TDZ对白刺花下胚轴和子叶胚性愈伤组织的诱导;在MS培养基上添加不同浓度2,4-D,研究胚性愈伤组织增殖情况;采用ABA,探究对体细胞胚发生的影响。结果表明:下胚轴比子叶更易诱导胚性愈伤组织,筛选出2种外植最佳的胚性愈伤组织诱导培养基均为MS+2.0 mg/L 2,4-D+0.5 mg/L TDZ+0.5 mg/L 6-BA,胚性愈伤组织诱导率分别为77.3%和41.0%。15.0 mg/L ABA、0.2 mg/L 2,4-D和2.0 mg/L 6-BA有利于体细胞胚发生,1/3MS+0.2 mg/L NAA+0.1 mg/L 6-BA+2.0 g/L活性炭+25 g/L蔗糖+7 g/L琼脂的培养基可使体细胞胚萌发率达80%以上,再生植株移栽成活率高达90%。白刺花外植体种类及培养基类型均会影响胚性愈伤组织的诱导,其中下胚轴诱导效果优于子叶;MS培养基较适合启动细胞脱分化形成愈伤组织,2,4-D对胚性愈伤组织的增殖保持有调控作用,ABA有利于体细胞胚的发生。     

曼陀罗茎段愈伤组织诱导和再生植株的研究

本试验以曼陀罗茎段为外植体,在附加不同植物激素组合的培养基中对愈伤组织的诱导和植株再生进行研究。结果表明:采用修改的MS培养基(除去甘氨酸,维生素B1含量增加至0.5mg/L,pH5.5)附加2mg/L2,4-D可由曼陀罗茎段诱导大量胚性愈伤组织;愈伤组织继代选用0.5mg/L2,4-D为宜;不定芽的诱导采用MS培养基(20g蔗糖,8g琼脂,0.1g水解干酪素) 6-BA(0.5mg/L);幼苗进一步转接至1/2MS IBA(0.2mg/L)生根培养基中,可完成曼陀罗茎段愈伤组织诱导和再生植株的组织培养过程。     

新疆雪莲植株再生体系研究初探

以新疆雪莲叶片、叶柄和根为外植体,诱导新疆雪莲植株再生,获得愈伤组织诱导、分化和生根最佳培养基,并初步建立其再生体系.研究结果表明:所用培养基均能诱导出愈伤组织且诱导率最高可达100%,分化率最高可达78%.对不同外植体的愈伤组织诱导结果表明:叶片和叶柄的诱导效果最好,根的诱导效果较差.其中对叶片愈伤组织诱导效果最好的培养基是MS+NAA0.50 mg/L+2,4-D0.10 mg/L+6-BA1.00mg/L,对叶柄的诱导效果最好的培养基是MS+NAA1.00mg/L+2,4-D0.10mg/L+6-BA0.10mg/L;分化培养基以MS+NAA0.20 mg/L+6-BA1.00mg/L较适宜,生根培养基以1/2MS0+NAA1.00mg/L较适宜.     

银杏愈伤组织生长、褐化与黄酮积累研究

旨在建立稳定的银杏愈伤组织继代体系,筛选细胞活性强且黄酮产量高的细胞培养条件,为工业化生产提供一定参考。以MS培养基为基本培养基,在40 d的继代周期内设计正交实验研究外植体月份、外源激素与抗褐化剂交互作用下的银杏愈伤组织生长、褐化与黄酮积累,并对比了4、5、6月中旬银杏叶片黄酮含量。结果表明,银杏愈伤组织继代中的最佳生长组合为:4月叶片诱导的愈伤组织+3.0 mg/L NAA+0.5 mg/L KT+5 mg/L VC;最佳抗褐化组合为:4月叶片诱导的愈伤组织+1.0 mg/L NAA+1.0mg/L KT+10 mg/L VC;银杏叶黄酮含量从4-6月呈上升趋势,且不同月份叶片诱导的愈伤组织黄酮含量与之呈正相关,以6月叶片诱导的愈伤组织+2.0 mg/L NAA+1.0 mg/L KT+5 mg/L VC为最佳黄酮积累条件;结合愈伤组织干重,总黄酮实际产量最高组合为:5月叶片诱导的愈伤组织+2.0 mg/L NAA+0.5 mg/L KT+5 mg/L VC。银杏愈伤组织的适宜继代周期为24-32 d,生长量较大且褐化率低。     

抗茎枯病芦笋品种离体培养的研究北大核心CSCD

选用芦笋(Asparagus officinalis)茎枯病高抗品种格兰蒂为材料,研究各种生长素及细胞分裂素对其茎尖诱导的愈伤组织、不定芽增殖和生根的效果。实验结果表明,最适芦笋茎尖诱导愈伤组织的培养基为:MS+6-BA0.3 mg/L+2,4-D 1.5 mg/L+蔗糖25 g/L+琼脂7 g/L,pH 5.8;最适愈伤组织增殖诱导、分化不定芽的培养基为:MS+NAA 0.3 mg/L+6-BA 0.5 mg/L+蔗糖30 g/L+琼脂7 g/L,pH 5.8;最适生根培养基为:1/2 MS+0.5 mg/L IBA+1 mg/L PP333+0.3 mg/L 6-BA+蔗糖30 g/L+琼脂7 g/L,pH 5.8。     

野葛块根脱分化与再分化相关因子研究

采用正交试验、单因子试验和植物组织培养方法,探讨几种因子对野葛块根组织脱分化与再分化的影响。结果表明,野葛块根愈伤组织诱导的最佳培养基为MS+NAA 0.5mg/L+6-BA 1.0mg/L+2,4-D 2.0mg/L,暗培养更有利于愈伤组织的诱导;野葛块根愈伤组织的最佳出芽培养基为MS+NAA 0.5mg/L+6-BA 3.0mg/L或MS+NAA 0.5mg/L+KT 2.0mg/L,光照培养更有利于愈伤组织芽的再分化;野葛块根愈伤组织再生芽生根最佳培养基为MS+NAA 0.5mg/L+PP₃₃₃ 3.0mg/L+蔗糖30g/L;PP₃₃₃ 3.0mg/L和蛭石:珍珠岩(2:1)基质能显著提高再生苗的移栽成活率。     

如意皇后粗肋草愈伤组织及丛生芽诱导培养基优化

本研究以粗肋草‘Red Valentine’带侧芽的根茎为外植体,研究不同培养基类型、不同外源激素及浓度、不同转接周期对其愈伤组织及丛生芽诱导的影响,进而优化如意愈伤组织和丛生芽诱导培养基。结果表明:最佳愈伤组织诱导培养基为MS+0.5 mg/L TDZ+2.0 mg/L 2,4-D和1/2MS+0.5 mg/L TDZ+2.5 mg/L 2,4-D;最佳愈伤组织分化培养基为1/2 MS+0.4 mg/L TDZ,最佳转接周期为30 d;最佳丛生芽诱导培养基为5.0 mg/L6-BA+0.2 mg/L NAA和1/2 MS+0.5 mg/L TDZ,最佳转接周期为30 d。优化培养基后愈伤组织及丛生芽诱导效率更高。本研究通过设计优化试验,筛选出了愈伤组织诱导及丛生芽诱导的最佳培养基,为粗肋草属植物的快速繁殖及规模化生产提供了一定的理论指导。     

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.