鞭檐犁头尖中的苯丙素甙类化合物

从天南星科植物鞭檐犁头尖的根茎中分离得到3个化合物,运用波谱技术(UV,IR,^1HNMR,^13C NMR and 2D NMR)对它们的化学结构进行解析,分别鉴定为松柏甙(1),甲基松柏甙(2)和硝酸钾(3)。从鞭檐犁头尖中分离得到苯丙素甙类化合物尚属首次。     

南海海绵Dysidea sp.的化学成分研究

从我国南海陵水地区采集的一种未定种海绵Dysideasp中首次分离到7个化合物,经MS,NMR等光谱技术,确定了结构分别为胆固醇(1),过氧化麦角甾醇(2),cholesl-7-en-9a,11α-epoxy-3β,5α,6β,19-tetraol-6-monoacetate(3),甲基尿嘧啶(4),尿嘧啶(5),甲基尿嘧啶脱氧核糖核苷(6),尿嘧啶脱氧核糖核苷(7)。其中化合物3的^1H NMR和^13C NMR数据通过二维NMR实验首次得到了全归属。     

从中国红豆杉细胞培养物中分离鉴定紫杉醇

中国红豆杉(Taxus chinensis(Pilger．)Rehd)细胞在培养过程中合成了紫杉醇,我们利用固液分离、大孔吸附树脂吸附富集、有机溶剂萃取、硅胶柱层析、低压硅胶柱层析、重结晶等方法,从中国红豆杉的细胞培养物中分离纯化了紫杉醇,用多种核磁共振波谱方法(^1H NMR,^13C NMR,DEPT,^1H-^1H-COSY,NOESY,HMQC,HMBC)结合质谱(FABMS),红外光谱、紫外光谱等方法鉴定了它的化学结构,证明与源于天然红豆杉植物材料提取的紫杉醇为同一物质。     

田基黄(口山)酮成分的研究

采用萃取,硅胶及凝胶柱色谱等方法从田基黄全草中分离得到了7个San酮类化合物,利用UV、IR、^1H NMR、^13C NMR、MS等波谱技术将他们的结构分别鉴定为6-脱氧异巴西红厚壳素(1)、异巴西红厚壳素(2)、1,3,5,6-四羟基San酮(3)、1,3,6,7-四羟基San酮(4),1,3,5,6-四羟基-4-异戊烯San酮(5)、1,3,5-三羟基San酮(6)和bijaponicaxanthone(7),其中化合物3、4和6为首次从该植物中分得的San酮类化合物。     

假地枫皮中二萜酸类化合物研究

从八角属植物假地枫皮的石油醚提取物中分离出5个二萜酸类化合物,经波谱数据分析(^1H NMR、^13C NMR、^1H-^1H COSY、NOESY、HSQC和HMBC),分别鉴定为4-epi-dehydroabietic acid(1)、4-epi-sandaraeopinaric acid(2)、4-epi-abietic acid(3)、4-epi-isopimaric acid(4)和8,11,13,15-abietatetraen-19-oic acid(4)。     

台湾扁柏化学成分研究进展

从植物台湾扁柏（Chamaecyparis obtusa var．formosana）中提取分离得到一百多种化合物,这些化合物大多结构新颖、具有较强生理活性,主要有倍半萜类、双萜类、木酚素类、固醇类以及其它化合物。本文综述了从该植物中得到的各类化学成分的结构和^13C NMR谱图数据。     

珠芽蓼果实化学成分研究

利用硅胶柱层析分离和Sephadex LH20纯化等方法从珠芽蓼果实分离得到6个化合物,经^1H NMR、^13C NMR等技术及理化性质鉴定为β-谷甾醇、胡萝卜苷、没食子酸、正丁基—β—D吡喃果糖苷、槲皮素—5—O—β—D—葡萄糖苷、蔗糖。6种化合物均为首次从该植物分离得到。     

长毛风车子的化学成分研究

对采自海南三亚的长毛风车子(Combretum pilosum Roxb)的化学成分进行研究。应用硅胶、Sephadex LH-20等柱色谱技术进行分离纯化,并运用现代波谱技术(EI-MS,1H NMR,13C NMR)进行结构鉴定。从长毛风车子中分离得到了7个化合物,分别为木栓酮(1)、常春藤皂苷元(2)、植物醇(3)、香荚兰醛(4)、β-谷甾醇(5)、乌苏酸(6),羽扇豆醇(7)。以上化合物均为首次从该植物中分离得到。     

鸦胆子的化学成分

对苦木科鸦胆子属植物Brucea javanica（L）Merr的成熟果实鸦胆子提取物的化学成分进行分离鉴定。鸦胆子乙醇提取物经氯仿萃取,硅胶柱色谱分离,通过波谱（^1H NMR,^13C NMR）分析和化学方法鉴定其结构。从中药鸦胆子中分离得到6个苦木内酯类化合物即brusatol（1）、bmeeine D（2）、bruceine E（3）、bruceine F（4）、bmceine A（5）、bruceoside A（6）,另外还有β-谷甾醇（β-sitosterol,7）、胡萝卜苷（daueosterol,8）。     

黄花棘豆生物碱成分研究

采用硅胶柱层析、Sephadex LH-20和半制备HPLC等色谱手段对草原毒草黄花棘豆(Oxytropis ochrocephala Bunge)生物碱成分进行分离纯化,从全草提取物中分离得到8个生物碱成分。利用MS、1H NMR和13C NMR波谱技术鉴定化合物结构为槐定碱(1)、槐胺(2)、异槐定碱(3)、苦参碱(4)、7,11-去氢苦参碱(5)、槐果碱(6)、羽扇豆碱(7)和苦马豆素(8)。化合物1~6为首次从棘豆属植物中分离得到。     

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.