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1.
栗柄金粉蕨的黄酮类成分   总被引:3,自引:0,他引:3  
从栗柄金粉蕨( Onychium lucidum ) 地上部分的甲醇抽提物中分到10 个成分, 经详细的一维、二维核磁数据分析, 它们被鉴定为: 木犀草甙(1) , 3 , 7 - 二甲基槲皮素(2) , 高山甙B (3) , 金粉蕨素(4) , 栗柄醇(5) , 金粉蕨醇B(6) , β- 谷甾醇(7) , 胡萝卜甙(8) ,齐墩果酸(9) 和蔗糖(10) 。栗柄醇系新成分。1 , 2, 9 系首次由金粉蕨属分到。  相似文献   

2.
紫茎泽兰的化学成分   总被引:32,自引:1,他引:31  
从紫茎泽兰(EupatoriumadenophorumSpreng)中分离得到8个化合物,其中3-(2′-β-O-吡喃葡萄糖)-苯基-2-反式丙烯酸为一新化合物,其余为槲皮万寿菊素-7-β-O-葡萄糖甙,6-甲氧基山奈酚-7-甲基醚-3-β-O-吡喃葡萄糖甙,槲皮万寿菊素-4′-甲基醚-7-β-O-葡萄糖甙,6-羟基山奈酚-7-β-O-葡萄糖甙,6-甲氧基芜花素,伞形花内酯及正三十二醇。  相似文献   

3.
飞机草中的化学成分   总被引:16,自引:0,他引:16  
从飞机草(Eupatorium odoratum Linn)中分离得7个化合物,经光谱分析鉴定为:山萘酚-4'-甲基醚(1),槲皮黄素7,4'-二甲基醚(2),刺槐素(3),柑桔素-4'-甲基醚(4),豆甾醇(5),β-谷甾醇(6)及β-胡萝卜甙(7)。  相似文献   

4.
鞭打绣球中的苯丙素甙和环烯醚萜甙   总被引:6,自引:0,他引:6  
从鞭打绣球(HemiphragmaheterophyllumWall.)(玄参科)的全草中分离到2个新的苯丙素甙,命名为鞭打绣球甙A和B(hemiphrosideAandB),2个已知的苯丙素甙,plantamajoside和plantainosideD,以及3个已知的环烯醚萜甙,globularicisin,globularin和iso-scrophularioside.通过化学和光谱分析,鞭打绣球甙A和B的结构分别鉴定为2-(3-羟基-4-甲氧基苯基)乙基0-β-D-葡萄吡喃糖基(1→3)-4-O-反式阿魏醚基-β-D-葡萄吡喃糖试和2-(3,4-二羟基苯基)乙基O-[6-O-乙醚基-β-D-葡萄吡喃糖基(1→3)]-4-O-反式咖啡醚基-β-D-葡萄吡喃糖甙.  相似文献   

5.
高山金粉蕨的黄酮类成分   总被引:3,自引:0,他引:3  
从高山金粉蕨(Onychiumcontigqum)地上部分的甲醇抽提物中分到8个成分:高山金粉蕨甲甙(1),高山金粉蕨乙甙(2),金粉蕨素(3),反式桂皮酸(4),瓦利甙(5),β-谷甾醇(6),胡萝卜甙(7)和蔗糖(8)。高山金粉蕨甲甙和乙甙是新成分,反式桂皮酸系首次从金粉蕨属中分到。化学结构用一维和二维核磁共振技术确定。  相似文献   

6.
云木香化学成分研究 II   总被引:7,自引:0,他引:7  
从丽江产云木香(SaussrealappaC.B.Clarke)根中分离得到的另外7化合物,它们分别是孕甾炮醇酮(pregnenolone)(1),β-谷甾醇(β-sitosterol)(2)葫萝卜甙(daucosterol)(3),苯丙素甙(syringin)(4),木质素甙(1-hydroxypinoresinol-1-β-D-glucopyranoside)(5)油酸(z,z)-9,12-o  相似文献   

7.
假朝天罐的化学成分研究   总被引:6,自引:1,他引:6  
从假朝天罐(Osbeckia crinita Benth.)的地上部分分离得到六个化合物,β-谷甾醇、熊果要到、胡萝卜甙、槲皮素-3-鼠李糖甙、槲皮素-3-葡萄糖甙、槲皮素,均是首次从扣坡素-3-鼠李糖甙是首次从该属植物中获得。  相似文献   

8.
中药玄参的化学成分   总被引:8,自引:0,他引:8  
从中药玄参(ScrophularianingpoensisHemsl.)中分离得到1个新化合物:4-O-(对甲氧基肉桂酰基)-α-L-鼠李糖[4-O-(p-methoxycinnamoyl)-α-L-rhamnopyranose];同时还分离到4个已知的环烯醚萜甙:爪钧草甙(harpagide),爪钩草酯甙(harpagoside),O-甲基梓醇(O-methylcatalpol),士可玄参甙A(scropoliosideA)和1个已知的苯丙素甙:安格洛甙C(angorosideC)。新化合物的结构通过化学降解和光谱分析得到证明。  相似文献   

9.
从栗柄金粉蕨(Onychium lucidum)地上部分的甲醇抽提物中分到10个成分,经详细的一维、二维核磁数据分析,它们被鉴定为木犀草甙(1),3,7-二甲基槲皮素(2),高山甙B(3),金粉蕨素(4),栗柄醇(5),金粉蕨醇B(6),β-谷甾醇(7),胡萝卜甙(8),齐墩果酸(9)和蔗糖(10)。栗柄醇系新成分。1,2,9系首次由金粉蕨属分到。  相似文献   

10.
藏药黑边假龙胆的化学研究   总被引:8,自引:0,他引:8  
龙胆科植物黑边假龙胆(Gentianellaazurea(Bunge)Holub)是治疗肝胆湿热的1种藏药,从西藏日喀则产的全草中分离得到9个化合物,其中1个C一甙黄酮,异荭草素(isoorientin);1个山酮甙,獐牙菜酚甙(swertianolin);1个木质体甙,橄榄脂素4一O一β-D-葡萄糖甙(olivil4一O一β一glucoside);3个环烯醚萜甙,龙胆苦甙(gentiopicroside),獐牙菜甙(swertiamarin)和马钱子酸(loganicacid);1个三萜,齐敦果酸(loeanolicacid)1个甾醇,β谷甾醇葡萄糖甙(daucosterol)以及1个长链脂肪醇,三十烷醇(n一1一triacontanol)。它们的结构通过光谱和化学的方法得到了鉴定。上述结果,从次生代谢产物的角度为假龙胆属在系统分类上与龙胆属和獐牙菜属有着密切的联系提供了旁证。  相似文献   

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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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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   

17.
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   

18.
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   

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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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