翻白草根中可水解丹宁的研究

从蔷薇科植物翻白草根的70％含水丙酮提取物中,利用Toyopearl HW-40等柱层析分离,精制,分得5种多元酚类化合物。经化学及波谱方法证明,这5种化合物分别为:可水解丹宁agrimoniin(1),gemin A(2),pedunculagin(3),casuarictin(4)及tellima-grandin Ⅱ(5)。上述化合物均系首次从该植物中分得。     

苍白秤钩风中脱皮甾酮类化学成分的研究

从中国广西药用植物苍白秤钩风(Diploclisia glaucescens)藤茎的95％乙醇提取物中分离得到5个脱皮甾酮类化合物(1-5)。通过NMR、MS以及化学沟通等方法分别将其结构鉴定为paristerone C-20,22-monoacetonide(1),paristerone(2),eodysterone(3),makisterone C(4)和capisterone(5)。化合物1为首次从自然界分得的天然产物,2,4,5亦为首次从该植物中分得。     

中药王不留行化学成分的研究

从河北产麦蓝菜(Vaccaria segetalis(Neck)Garcke.)的种子王不留行中分离得到5个化合物,经波谱分析和化学方法分别鉴定为:Tetracosanoic acid(1),E-3-phenyl-2-Propenoic acid(2),stigmast-7,22-dien-3-ol(3),stigmast-7,22-dien-3-ol 3β-O-[β-D-glucopy-ranoside](4),9,12-octadecadienoic acid N-(2-hydroxyethyl)(5)。以上各化合物都是首次从该植物中分得。化合物5为首次从天然界分得。     

羊耳朵叶化学成分的研究

从羊耳朵叶(密蒙花 Buddle ja officinalis Maxim的叶)中分得8个化合物,分别鉴定为3个萜:羽扇豆醇乙酸酯(lupeol acetute)(1),cycloeucalenol(2),chondrillasterol(3)和5个苯丙素酚甙:verbascoside((4),poliumoside(5),β-hydroxyacteoside(6),echinacoside(7)和cistanoside F(8)。化合物1,2,3为首次从该属植物中获得。     

东北石杉生物碱成分的研究

从东北石杉中分离得到7个石松生物碱,通过NMR、MS及IR等光谱分析,分别鉴定为：luciduline(1),dithydroluciduline(2),lycocline(3),huperzine B(4),serratinine(5),serratidine(6),mecleanine(7)。这些化合物均为首次从该植物中分得。     

桑白皮化学成分的研究

从桑白皮(Cortex Mori)的水提液中分离得到5个化学成分,通过波谱数据结合理化性质分别鉴定为4,4’-二苯甲烷二氨基甲酸甲酯(4,4’-diphenylmethane-bis(methyl)carbamates,1),东莨菪内酯(seopoletin,2),伞形花内酯(umbelliferone,3),3,4,5-三甲氧基苯酚(3,4,5-trimethoxyphenol,4),对羟基苯甲酸乙酯(4-hydroxy ethyl-benzoate,5)。其中,化合物1为新的天然化合物,4和5为首次从该植物中分得。     

蕺叶秋海棠化学成分的研究

从蕺叶秋海棠(Begoma limprichtu Irmsh)全草中分得5个化合物,经理化性质和波谱分析,分别鉴定为:豆甾醇-3-O-β-D-葡萄糖甙-6’-十六烷酸酯(1),豆甾醇3-O-β-D-吡喃葡萄糖甙(2),芦丁(3),豆甾醇(4),胡萝卜甙(5)。     

麦冬块根化学成分的研究

从麦冬(Ophiopogon japornicus)块根中分得两个环二肽类化合物,一个酰胺类化合物和一个多羟基脂肪酸类化合物。通过光谱数据分析,分别鉴定为eyclo-(Phe-Tyr)(1),cyclo-(Leu-ILe)(2),N-(2．(4-hydroxyphenyl)ethyl)-4-hydroxycinnamide(3)和天师酸(4)。这四个化合物均为首次从沿阶草属植物分得。环二肽类化合物为首次从沿阶草属植物中分得的化合物类型。     

桑色素和桑色素-钙络合物的分离和鉴定

从滇产菠萝蜜(Artocapus pithecogallus C.Y.Wu.)和牛肚子果(Artocapus heterophyllusLan·)树心材中分得桑色素(morin)(Ⅰ),从后者还分得一种黄绿色的结晶,经光谱分析、衍生物制备和合成品对照,证明为桑色素-钙的络合物——桑色素的5-位上的羟基氢被钙原子取代并与4-位酮基相螯合的络合物(morin-calcium chelate compound)(Ⅱ)。     

肉苁蓉中苯乙醇甙类成分的分离和鉴定

从列当科药用植物肉苁蓉(Cistanche deserticola)中分得四个苯乙醇甙类成分,经光谱分析,确定这四个成分是海胆甙(echinacoside),肉苁蓉甙A(cistanoside A),麦角甾甙(acteoside)和2＇-乙酰麦角甾甙(2＇-acetylacteoside)。以上成分在该植物中属首次分得。     

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.