荔枝皮化学成分的研究(Ⅰ)

采用 Sephadex LH-20、MCI gel CHP 20P 和 Toyopearl Butly-650C 等柱色谱,反复对80％乙醇荔枝皮提取物进行分离、纯化,得到7个多酚类化合物。根据波谱分析以及文献数据对比,分别鉴定为对羟基苯甲酸(1)、原儿茶酸(2)、(＋)儿茶素(3)、(-)表儿茶素(4)、原花青素 A2(5)、aesculitannin A(6)、槲皮素-3-O-β-D-葡萄糖苷(7)。除5以外的化合物均为首次从荔枝果皮中分离得到。     

蓝桉果实中的脂溶性成分

从蓝桉(Eucalyptus globulusLabill.)果实乙醇提取物的石油醚部位分离鉴定出6个化合物,通过理化和波谱分析结构鉴定为:5-羟基-4′,7-二甲氧基-6-甲基黄酮(1)、blumenol A(2)、蓝桉醇(3)、绿花白千层醇(4)、β-谷甾醇(5)、二十二烷酸(6),其中化合物1~4和化合物6系首次从该植物中分离得到,化合物1和2首次从桉属植物中分离得到.     

蒙药材莲座蓟化学成分的研究

从莲座蓟(Cirsium Esculentum C.A.Mey)植物的根及根茎中分离得到6个化合物,经波谱数据分析分别鉴定为β-谷甾醇(1)、5,7-二羟基-6,4’-二甲氧基黄酮(2)、刺槐素(3)、β-胡萝卜苷(4)、蒙花苷(5)、绿原酸(6)。上述化合物均为首次从该植物中分离得到。     

木荷茎皮化学成分研究

综合使用硅胶柱色谱、HP20大孔树脂柱色谱、ODS反相柱色谱及Sephadex LH-20凝胶柱色谱等色谱技术对木荷(Schima superba)茎皮进行分离纯化,并根据化合物理化性质以及应用MS、NMR技术对分离得到的化合物进行结构鉴定。从木荷中分离得到9个化合物,分别鉴定为三十烷酸(1)、棕榈酸(2)、Dodecanoic acid(3)、松脂素(4)、槲皮素(5)、山柰酚(6)、Americanin A(7)、槲皮素-3-O-β-D-葡萄糖苷(8)及槲皮素-3-O-α-L-鼠李糖苷(9)。化合物1～4 为首次从木荷中分离得到,化合物5、7、9 为首次从木荷属植物中分离得到。     

琐琐葡萄化学成分研究

采用大孔树脂、聚酰胺和Sephadex LH-20柱从琐琐葡萄乙醇溶液中分离得到六个化合物,通过波谱学技术及理化手段分别鉴定为齐墩果酸(1)、异槲皮苷(2)、槲皮素-3-O-β-D-葡萄糖醛酸钠盐(3)、槲皮素-3-O-β-D-葡萄糖醛酸乙酯苷(4)、没食子酸(5)、单咖啡酰酒石酸(6)。其中化合物2~6为首次从该植物中分离得到,化合物2~4为首次从该属植物中分离得到。     

海洋放线菌Streptomyces variabilis strain 6-1次级代谢产物的研究

目的:对来自海洋软珊瑚的链霉菌6-1(Streptomyces variabilis strain 6-1)进行次级代谢产物的分离和鉴定,寻找具有生物活性的化合物,为人类健康服务。方法:采用液体培养基对分自海洋软珊瑚Scleronephthya sp中的链霉菌6-1(Streptomyces variabi-lis strain 6-1)进行发酵培养,用乙酸乙酯对发酵液进行萃取;采用半制备高效液相色谱(semi-preparative HPLC)分离方法对乙酸乙酯萃取物进行分离纯化,得到单体化合物;运用电喷雾质谱(ESI-MS)、核磁共氢振(1H NMR)、核磁共振碳谱(13C NMR)和物理性质对所得单体化合物进行结构鉴定。结果:从海洋链霉菌6-1(strain 6-1)发酵液的乙酸乙酯萃取物中分离得到3个单体化合物,分别鉴定为:7,4'-二羟基异黄酮(1)、5,7,4'-三羟基异黄酮(2)和丁烯酸内酯-Ⅰ(3)。结论:丁烯酸内酯-Ⅰ是从链霉菌属首次分离得到,化合物1和2均是从Streptomyces variabilis中首次分离得到;变异链霉菌6-1(Streptomyces variabilis strain 6-1)可以作为活性化合物3(丁烯酸内酯-Ⅰ)的重要来源。     

肾蕨的化学成分研究

从肾蕨乙醇提取物中分离得到6个化合物,根据理化和光谱分析,鉴定为β-谷甾醇(1)、羊齿-9(11)-烯(2)、齐墩果酸(3)、肉豆蔻酸十八烷基酯(4)、正三十一烷酸(5)和正三十烷醇(6),化合物3～6为首次从该植物中分离得到。     

黑果枸杞正丁醇部位的酚性化合物

采用色谱法从黑果枸杞中分离得到7个化合物,借助波谱学方法鉴定了它们的结构,分别鉴定为2-O-(3-甲氧基4,5-二羟基苯甲酰基)-4-羟基-6-O-β-D-吡喃葡萄糖基苯乙酸(1)、绿原酸(2)、绿原酸甲酯(3)、glucoacetosyringone(4)、丁香酸(5)、对羟基苯甲醛(6)和3,4-二羟基-5-甲氧基苯甲酸甲酯(7)。其中化合物1为新化合物,化合物4和7为首次从本属中被分离得到。     

紫红獐牙菜口山酮及环烯醚萜类化合物的研究

采用各种柱色谱法对紫红獐牙菜的石油醚和正丁醇部位进行分离纯化,从石油醚部位分离鉴定得到6个化合物,利用理化性质和波谱学方法分别鉴定为oleanolic acid(1),swerchirin(2),sweriaperenine(3),bellidifo-lin(4),gentiacaulein(5)和1,7,8-trihydroxy-3-methoxyxanthone(6);从正丁醇部位分离鉴定得到9个化合物,分别鉴定为8-[(β-D-glucopyranosyl)oxy]-1,5-dihydroxy-3-methoxyxanthone(7),5-[(β-D-glucopyranosyl)oxy]-1,8-di-hydroxy-3-methoxyxanthone(8),7-[(β-D-xylopyranosyl)oxy]-1,8-dihydroxy-3-methoxyxanthone(9),8-[(β-D-gluco-pyranosyl)oxy]-1,3,5-trimethoxyxanthone(10),swertiamarin(11),tetrahydrosertianolin(12),8-hydroxy-10-hydro-sweroside(13),campestroside(14)以及uridine(15)。其中,化合物15首次从该属植物中得到,化合物9、10、12和13首次从该植物中分离得到。     

遍地金的化学成分研究Ⅱ

从遍地金(Hypericum wightianum Wall．ex Wight et Am．)乙醇提取物中分离得到3个化合物,经波谱分析鉴定为6-deoxyisojacareubin(1),6-异戊烯基槲皮素-3-甲醚(2)和香草酸(3)。3个化合物均为首次从该植物中分离得到。     

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.