云南拟单性木兰的组织培养

1植物名称云南拟单性木兰(Parakmeria yunnanensis Hu). 2材料材料采用茎尖和带腋芽的茎段.     

灰黑拟牛肝菌的化学成分

从担子菌灰黑拟牛肝菌（Boletopsis grisea)新鲜子实体的乙醇提取物中首次分离得到10个化合物,包括8个酚性成分,1个含硫成分和1个脑苷脂,它们的结构经各种波谱数据分别鉴定为3－（4－乙酰氧基苯）－1,2,4,7,8－五乙酰氧基二苯并呋喃（1）,3－（4－乙酰氧基苯）－1,2,4－三乙酰氧基－7,8－二羟基二苯并呋喃（2）,3－（4－羟基苯）－1,2－二乙酰氧基－4,7,8－三羟基二苯并呋喃（3）,2,3－二乙酰氧基－4′,4″,5,6－四羟基对联三苯（4）,对苯二酚（5）,对羟基苯甲酸（6）,茴香酸（7）,对羟基苯甲醛（8）,硫代乙酐（9）和1－O－吡喃葡萄糖基－（2S,3R,4E,8E,2′R）-2-N-(2′-羟基棕榈酰）－9－甲基－4,8－sphin-gadienine(10)。其中化合物1,2,3有报道对5－脂氧化酶具有选择性抑制活性。4,9,10均为首次从该属真菌中分离得到。     

峨眉拟单性木兰群落特征的初步研究

对峨眉山峨眉拟单性木兰群落特征与种群结构的初步研究表明:1、蛾眉拟单性木兰及其群落分布局限,地形、土壤、气候条件较为特殊;2、该群落与中国云南和东部亚热带常绿阔叶林具有广泛的联系,并具各“顶极群落”的特征;3、峨眉拟单性木兰林的两个基木群丛为:(A)蛾眉拟单性木兰+四川人头茶+包石栎-箭竹-苔草群丛与 (B)黄心夜合+大叶新木姜子+峨眉拟单性木兰-箭竹-单芽狗脊群丛;4、人类和猴群的活动与干扰直接威胁着该种种群和群落的生存与稳定。     

短瓣花中的含氮化合物

从云南民间草药短瓣花（Brachystemma calycinum D.Don)根的乙醇提取物中首次分到6个化合物,包括5个含氮化合物及1个可能的人工产物。它们的结构经光谱及化学方法鉴定为短瓣花苷A（brachystemoside A,1),L- 焦谷氨酸甲酯（methyl L-pyroglutamate,2),腺嘌呤核苷（adenosine,3),2-吡咯甲酸（2－minaline,4),吡咯－2－羧酸－3'－糖酯（3'-furfuryl-pyrrole-2-carboxylate,5)及α－D－乙基葡萄糖苷（ethyl α－D－glucopyranoside,6)。其中化合物1为新化合物。     

云南拟单性木兰挥发物质及其抗肿瘤和抑菌活性初步研究

采用水蒸气回流法提取挥发油,用气相色谱-质谱(GC-MS)联用技术分析云南拟单性木兰叶部精油的化学组成,共鉴定了31种成分的化学结构与相对含量,占总含量的99.997%。其中主要成分为石竹烯氧化物(16.979%)、(-)-斯巴醇(7.786%)、菖蒲烯(5.338%)、3,7-二甲基-2,6-辛二烯-1-醇(5.306%)、τ-杜松醇(5.204%)。体外对大肠杆菌和金黄色葡萄球菌供试病原菌的抑菌实验表明,该挥发油对金黄色葡萄球菌有一定的抑制能力。浓度为100μg/mL时,MTT法测定云南拟单性木兰挥发物质对肺癌细胞的抑制率为63.2%。     

云南割舌树的化学成分

从云南割舌树（Walsura yunnanensis C.Y.Wu.)树皮的乙醇提取物中分离鉴定了12个化合物,它们分别是walsurol(1),tocopherol(2),sitoindoside Ⅰ（3）,3β-stigmast-5-en-3-yl-β-D-xylopyranoside(4),stigmast-4-en-6β-ol-3-one(5),7-oxositosterol(6),3β-hydroxy-5α,8α-epidioxyergosta-6,22-diene(7),(-)epicatechin(8),3,5-dihydroxy-4-methoxylphenylethanol(9),间三甲氧基苯,（β－谷甾醇和胡萝卜甙,新化合物1命名为割舌醇（walsurol)。     

峨眉拟单性木兰的开花生物学特性与繁育系统

为阐明峨眉拟单性木兰(Parakmeria omeiensis)在自然条件结实率低的原因和确定最佳人工授粉时期,该文通过观察峨眉拟单性木兰的开花动态,采用杂交指数估算、花粉胚珠比、花粉活力及柱头活性检测、人工授粉试验等方法对其繁育系统进行了研究。结果表明:(1)植物园保育的峨眉拟单性木兰花期在4月底到5月中下旬,持续17～23 d,雄株始花期比雌株早3～4 d,但两者花期可遇。(2)两性花经检测雄蕊败育,实为功能上的雌性,部分雄株个体的雄花上残留1～2个心皮,其性别分化是通过雌、雄蕊选择性败育形成的,为隐性雌雄异株(cryptic dioecy)。(3)雄花、两性花开放经历佛焰苞开裂、花被片开裂、展开、闭合、二次开放、凋落6个阶段,历时4 d。(4)雄花初次展开时花粉活力最高,达92.8%,开花2 d后活力显著下降;两性花柱头在花被片展开期可授性最强,盛开后柱头部分可授。(5)杂交指数为5,P/O比为2.14×10~4。(6)套袋试验表明,峨眉拟单性木兰不能进行自花传粉,人工异花授粉的结实率和出种数显著高于自然授粉,且不存在无融合生殖。这说明峨眉拟单性木兰繁育系统为专性异交,传粉过程需要传粉媒介,自然条件下结实率低,主要是受传粉昆虫和柱头可授期短的限制。     

内生条纹拟盘多毛孢发酵液中细胞毒活性成分研究

从条纹拟盘多毛孢Pestalotopsis virgatula发酵液中分离得到8个化合物,其结构分别被鉴定为：2-(1-甲氧基-1-H-吲哚-3-基)乙醇 (1),2-(1-甲氧基-1-H-吲哚-3-基)乙酸 (2),3β-羟基-5α,8α-过氧化麦角甾-6,22-二烯 (3),麦角甾-4,6,8(14),22-四烯-3-酮 (4),对羟基苯乙醇 (5),邻苯二甲酸二异丁酯 (6),(E)-3-(4-羟基-3-甲氧苯基)败脂酸 (7) 和丁二酸 (8),化合物1–8均为首次从该菌种中分离得到。利用MTT法测试了化合物1 和2对5种人体肿瘤细胞的细胞毒活性,结果显示化合物1和2对5株肿瘤细胞株均具有一定选择性抑制活性。     

狗筋蔓中的植物蜕皮甾酮类化合物

从我国民间草药狗筋蔓（Cucubalus baccifer L.）全草的乙醇提取物的正丁醇萃取部分分离得到6个化合物,通过波谱及化学方法鉴定了它们的结构,分别为ecdysterone(1),24(28)-ecdysterone(2),22-deoxyecdysterone(3),25-hydroxypanuosterone(4),rubrosterone(5),2,22－dideoxyecdysterone 3β-O-β-D-glucopyranoside（6）。其中化合物6为新化合物;化合物1－5为首次从该植物中分得。     

云南透骨草的化学成分研究

从云南透骨草全草95%乙醇提取物中分离得到11个化合物,经波谱分析鉴定为山奈酚3-O-α-L-吡喃鼠李糖苷(1),番石榴苷(2),滇白珠甲苷(3),槲皮苷(4)(,-)-5’-甲氧基异落叶松脂醇9-O-β-D-木糖苷(5),五味子苷(6)(,–)-表儿茶素(7),异槲皮苷(8),金鸡纳素Ia(9),熊果酸(10)和2,5-双-(β-苯乙基)苯酚(11)。其中化合物1、2、9和11为首次从该植物中分得,化合物11是首次报导的天然产物。     

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.