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1.
艾纳香化学成分的研究   总被引:1,自引:0,他引:1  
从艾纳香(Blumea balsamifera DC.)中分离得到12个化合物,通过理化性质和波谱数据分析分别鉴定为;商路素(1),花椒油素(2),2,4-二羟基-6-甲氧基苯乙酮(3),5,7-二羟基色原酮(4),金丝桃苷(5),异槲皮苷(6),3′,4′,5,7-四羟基-3-甲氧基黄酮(7),槲皮素(8),槲皮素-3′-甲氧基-3-O-β-D-半乳吡喃糖苷(9),4′,5,7-三羟基-3,3′-二甲氧基黄酮(10),3,5,7-三羟基-3′,4′-二甲氧基黄酮(11),木犀草素(12).其中,化合物3-7和9- 11为首次从该属植物中分离得到.  相似文献   

2.
钩藤化学成分的研究   总被引:2,自引:0,他引:2  
从钩藤(Uncaria rhynchophylla(Miq.)Jacks.)带钩茎枝分离得到18个化合物,通过波谱学等方法鉴定为乌苏酸(1),27,28-二羧基乌苏酸(2),3β,6β,19α-三羟基乌苏酸(3),noreugenin(4),单棕榈酸甘油酯(5),3-酮-6β,19α-二羟基乌苏酸(6),sumresinolic(7),scopoletin(8),3β,6β,19α,24-四羟基乌苏酸(9),6-酮-3β,19α,23-三羟基齐墩果酸(10),3β,19α,24-三羟基乌苏酸(11),23-醛-3β,6β,19α-三羟基乌苏酸(12),钩藤苷元C(13),β-谷甾醇(14),胡萝卜苷(15),丁香酸(16),cleomiscosin D(17),cleomiscosin B(18).其中化合物4,7,9~11,17,18为首次从该植物中分离得到.  相似文献   

3.
从云南省会泽县产近无毛灰岩香茶莱〔Rabdosia calcicola (Hand. -Mazz.) Hara var. subculva (Hand. -Mazz.) C. Y. Wu et H. W. Li〕叶中分得两个二萜化合物,一个为新化合物,命名为灰岩香茶菜甲素(calcieolin A),另一个为已知化合物维西香茶菜甲素(weisiensin A),经各项光谱数据和化学反应确定,灰岩香茶菜甲素为3β-羟基-1α,6α,7β,11β-四乙酰氧基-对映-贝壳杉-16-烯-15-酮(1);维西香茶菜甲素结构应为3β,6α-二羟基-1α,7β,11β-三乙酰氧基-对映—贝壳杉-16-烯-15酮(2)。  相似文献   

4.
毛剪秋罗的化学成分研究   总被引:5,自引:0,他引:5  
从毛剪秋罗(Lychnis coronaria(L.)Desr.)全草的乙醇提取物中分离鉴定了11个已知化合物,经波谱分析确定其结构分别为tricin 7-O-glucopyranoside(1),(+)-isoscoparin(2),epoxyactinidionoside(3), 1α, 20R- hydroxyecdysone ( 4 ), ecdysterone ( 5 ), polypoding B ( 6 ), ecdysterone 22-O-β-D-glucopyranoside(7), stigmast-5-ene-3-one(8), taraxerol ( 9 ), a-tocopherol (10), dehydrodiconiferyl alcohol 4-O-β-D-gluoopyranoside(11).此外,还分离得到β-谷甾醇和胡萝卜苷.以上化合物均为首次从该植物中分离得到.  相似文献   

5.
石蝉草的脂溶性成分   总被引:1,自引:0,他引:1  
为研究石蝉草(Peperomia dindygulensis Miq.)的脂溶性化学成允,通过溶剂萃取、硅胶柱色谱、重结晶分离纯化,从石蝉草乙醇提取物的氯仿萃取部位分离得到7个化合物,经光谱学数据鉴定为:peperomin A(1),peperomin D(2),surinone C(3),proetorione C(4),cepharanone B(5),正十八酸(6),豆甾醇(7).化合物5为首次从该属植物中分离得到,除化合物1和2,其余所有成分均为首次从该植物中分离得到.  相似文献   

6.
云南割舌树的化学成分   总被引:4,自引:0,他引:4  
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)。  相似文献   

7.
藏药熏倒牛化学成分研究   总被引:2,自引:0,他引:2  
利用色谱对藏药熏倒牛进行化学成分研究.从藏药熏倒牛(Biebersteinia heterostemon Maxim.)中分离鉴定了6个化合物,采用波谱技术分别鉴定为hypolaetin 7-O-β-xylopyranoside (1)、山羊豆碱 (2)、反式-4-羟基山羊豆碱 (3)、甘露糖醇 (4)、伞形花内脂 (5)、槲皮素 (6).对化合物1的1H、13C NMR信号进行了准确归属,化合物1~4均为首次从该植物中分离得到.  相似文献   

8.
A novel C30 sterol, (22E, 24ξ)-24-n-propylcholest-7, 22-dien-3β-ol (racemosol, 1), along withscopoletin (2), scopolin (3), umbelliferone (4), methylβ-D-frucopyranoside (5), syringaresinol-4-O-β-D-glucopyranoside (6), quercetin-3-O-β-D-glucopyranoside (7), quercetin-3-O-α-L-rhamnopyranoside (8),eupatilin (9), kaempferol-3-O-β-D-glucopyranoside (10) and (E)-N-2-(2,3-dihydroxyphenyl) ethyl cinnamamide(11), was isolated from the whole plants of Porana racemosa Roxb. Their structures were elucidatedpredominantly by spectral evidence.  相似文献   

9.
小粒吴茱萸的化学成分研究   总被引:4,自引:0,他引:4  
从中药小粒吴茱萸(石虎)Evpdia rutaecarpa var.officinalis的近成熟果实中分离得到15个成分,分别为吴茱萸碱(evodiamine,1),吴茱萸次碱(rutaecarpine,2),羟基吴茱萸碱(hydroxyevodiamine,3),14-甲酰基二氢吴茱萸次碱(14-formyldihydrorutaecarpine,4),吴茱萸酰胺(evodiamide,5),吴茱萸酰胺-Ⅰ(goshuyuamide-Ⅰ,6),二氢吴茱萸新碱(dihydroevocarpine,7),茵芋碱(skimmianine,8),槲皮素-3-O-β-D-半乳糖甙(quercetin-3-O-β-D-galactoside,9),异鼠李素-3-O-β-D-半乳糖甙(isorhamnetin-3-O-β-D-galactoside,10);rutaevine(11);β-谷甾醇(β-sitosterol,12),胡萝卜甙(daucosterol,13);棕榈酸(palmaticacid,14),硬脂酸(stearicacid,15)。除了化合物1,2,3,7,11外,其余的10个化合物均是首次从该植物中得到。  相似文献   

10.
荷叶的化学成分研究   总被引:4,自引:0,他引:4  
从荷叶(Folium Nelumbinis)的乙醇提取物中分离鉴定出13个化合物,分别为荷叶碱(nuciferine,1),鹅掌楸碱(liriodenine,2),2-羟基-1-甲氧基阿朴啡(2-hydfoxy-1-methoxyaporphine,3),原荷叶碱(pronuciferine,4),去氢莲碱(dehydroroemerine,5),去氢荷叶碱(dehydronuciferine,6),莲碱(roemerine,7),胡萝卜苷(daucosterol,8),β-谷甾醇(β-sitosterol,9),1-二十烷醇(1-icosanol,10),1-十一烷醇(1-undecanol,11),(2R,4S,4aS,8aS)-4,4a-环氧-4,4a-二氢食用西番莲素[(2R,4S,4aS,8aS)-4,4a-epoxy-4,4a-dihydroedulan,12]和邻二羟基苯酚(benzene-1,2-did,13).其中化合物10~13为首次从荷叶中分离得到.  相似文献   

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13.
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.  相似文献   

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17.
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.  相似文献   

18.
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.  相似文献   

19.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
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  相似文献   

20.
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.  相似文献   

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