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1.
沙旋复花中的化学成分   总被引:3,自引:0,他引:3  
从沙旋复花[Inula salsoloides (Turcz.)Ostenf.]地上部份分得12种成分。根据其理化性质,化学反应及波谱分析,其中9种成分鉴定为蒲公英醇(Ⅰ)、蒲公英醇醋酸酯(Ⅱ)、蒲公英醇软酯酸酯(Ⅲ)、胡萝卜甙(Ⅳ)、木犀草素(Ⅴ)、豆甾醇(Ⅵ)、β-谷甾醇(Ⅶ),蜂花酸(Ⅷ)和泽兰内酯(Ⅸ)。这9种化合物均为首次从该植物中分得。(Ⅲ)和(Ⅸ)具有明显的细胞毒作用。  相似文献   

2.
蒲葵叶化学成分研究   总被引:4,自引:1,他引:4  
为研究传统药用植物蒲葵的化学成分,从蒲葵叶中分离得到5个化合物,分别鉴定为:3,5,7-三羟基-4′甲氧基黄酮醇(Ⅰ)、5,7,4′-三羟基黄酮-8-C-D-葡萄糖苷(Ⅱ)、β-谷甾醇(Ⅲ)、豆甾醇(Ⅳ)、二十六烷醇(Ⅴ)。该5个已知化合物均为首次从蒲葵叶中分离得到。  相似文献   

3.
蕺叶秋海棠化学成分的研究   总被引:8,自引:2,他引:6  
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)。  相似文献   

4.
紫茎泽兰化学成分的研究(Ⅰ)   总被引:8,自引:0,他引:8  
从云南紫茎泽兰(Eupatorium aclenophorum Spreng)茎、叶中分出10个化合物,经波谱(IR,MS,~1H-NMR,~(13)C-NMR)分别鉴定为9-oxo-ageraphorone(Ⅰ),9β-hydroxy-ager-aphorone(Ⅱ),表木栓醇(epifriedelinol,Ⅲ),豆甾醇(stigmasterol,Ⅳ),正二十八烷酸(octa-cosanoic acid,V),β-胡萝卜甙(β-daucosterol,Ⅵ),邻羟基桂皮酸(O-hydroxy cinnamic acid,Ⅶ),阿魏酸(ferulic acid,Ⅷ),咖啡酸(caffeic acid,Ⅸ),2-异丙烯基-5-乙酰基-6-羟基苯骈呋喃的乙酰化物(2-isopropenyl-5-acetyl-6-hydroxybenzofuran acetate,Ⅹ)。化合物(Ⅲ~Ⅹ)均系首次从该植物中分离到。  相似文献   

5.
小叶黄杨化学成分的研究   总被引:2,自引:0,他引:2  
小叶黄杨氯仿组分通过硅胶柱色谱分离纯化,从中分离得到9个化合物,分别鉴定为:β-谷甾醇(β-Sitosterol,Ⅰ)、豆甾醇(Stigmasterol,Ⅱ)、胡萝卜甙(daucosterol,Ⅲ)、水杨酸(salicylis acid,Ⅳ)、香草酸(vanillicacid,Ⅴ)、5,4′-二羟基-3,3′,7-三甲氧基-黄酮(5,4′-dihydroxy-3,3′,7-trimethoxy-flavone,Ⅵ)、5,4′-二羟基-3,3′,6,7-四甲氧基-黄酮(5,4′-dihydroxy-3,3′,6,7-tetramethoxy-flavone,Ⅶ)、Cleomiscosin A(Ⅷ)、3,5-二羟基-4′,6,7-三甲氧基-黄酮-3′-O-β-D-葡萄糖甙(3,5-dihydroxl-4′,6,7-trimethoxyl-flavone-3′-O-β-D-glucopyranoside,Ⅸ),其中化合物Ⅳ、Ⅴ、Ⅵ、Ⅶ均首次从该属植物中分离得到。  相似文献   

6.
牧马豆生物碱成分研究   总被引:3,自引:0,他引:3  
从豆科野决明属植物牧马豆(Thermopsis lanceolata R.Br.)的全草中分得五个生物碱.经物理常数测定及光谱分析,分别签定为:奥豆碱(Ⅰ),无叶豆碱(Ⅱ),13-0-Acetylbaptifoline(Ⅲ),黄华胺(Ⅳ)和N-甲醛基金雀花碱(Ⅴ).其中化合物Ⅲ和Ⅴ为首次从该种植物中分得.  相似文献   

7.
叉子圆柏中的抗肿瘤化学成分   总被引:4,自引:0,他引:4  
从叉子圆柏(Sabina vulgaris Ant.)的树皮中分得12种成分,根据其理化性质、化学反应及光谱分析,其中11种成分鉴定为反式璎珞柏酸(Ⅰ),顺式璎珞柏酸(Ⅱ),山达海松酸(Ⅲ),异柏油酸(Ⅳ)、柳杉酚(Ⅴ)、12-羟基-6,7-断松香烷8,11,13三烯6,7二醛(Ⅵ),β-足叶草素 A 早醚(Ⅶ),佛手内酯(Ⅷ),β-谷甾醇(Ⅹ),二十四烷酸(Ⅺ)和蜡酸(Ⅻ),另一种是新的3,4苯并香豆素类化合物,命名为圆柏内酯(sabilactone,Ⅸ),Ⅳ-Ⅹ为首次从该植物中分得。生物试验表明Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅵ和Ⅶ具有细胞毒作用。  相似文献   

8.
药用植物灯笼草的化学成分研究   总被引:3,自引:0,他引:3  
从药用植物灯笼草(Clinopvdium polycephalum)中分离鉴定了5个化合物。其中主要成分为乌索酸(ursolic acid,Ⅰ),其余4个分别鉴定为:异樱花素(isosakuranetin.Ⅱ),香蜂草甙(didymin,Ⅲ),6'-十六碳酸酯基-α-菠甾醇-3-O-β-D-葡萄糖甙(6’-Palmityl-α-spinasteryl-3-O-β-D-glucoside,Ⅳ a)和十八碳酸酯基-α-波甾醇-3-O-β-D-葡萄糖甙(6’-stearyl-α-spinasteryl-3-O-β-D-glucoside,Ⅳ b)。上述化合物在该植物中均为首次报道。  相似文献   

9.
紫珠叶的化学成分研究Ⅰ   总被引:3,自引:2,他引:3  
从马鞭草科紫球叶的乙醇提取物中分得5个化合物,经理化性质和光谱数据分别鉴定为:三十五烷(Ⅰ)、α-香树脂醇(Ⅱ)、四十五碳酸(Ⅲ)、5-羟基-4′,3,6,7-四甲氧基-黄酮(Ⅳ)、豆甾醇(Ⅴ)。除豆甾醇外,其余化合物均为首次从该属植物中分得。  相似文献   

10.
利用硅胶柱色谱、Sephadex LH-20柱色谱等手段从大头艾纳香(Blumea megacephala(Randeria)Chang etTseng)全草中分离得到13个化合物,根据化合物的理化性质和光谱数据分别鉴定为无羁萜(1)、小麦黄素(2)、豆甾醇二十六烷酸酯(3)、豆甾醇十八烷酸酯(4)、α-香树脂醇(5)、α-香树脂醇乙酸酯(6)、β-香树脂醇乙酸酯(7)、β-谷甾醇(8)、豆甾醇(9)、β-胡萝卜苷(10)、二十七烷醇(11)、十六烷酸(12)和二十四烷酸(13)。所有化合物均为首次从大头艾纳香中分离得到。  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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