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1.
贞桐的化学成分   总被引:1,自引:0,他引:1  
用正反相硅胶柱层析、中压柱层析、制备性薄层层析等手段,从贞桐中分离得到4个苯丙素甙类成分,根据光谱数据及化学方法,鉴定为马蒂罗甙(1),单乙酰马蒂甙(2),贞桐甙A(4)以及阿克甙(3),其中,贞桐甙A是一新化合物。同时还得到22,23-二氢菠甾醇,豆甾醇,25,26-去氢豆甾醇,乌索酸,丁二酸酐和小麦黄素等。  相似文献   

2.
大火草根部的化学成分   总被引:14,自引:1,他引:14  
大火草(Anemone tomentosaa(Maxim.)Pei)根状茎提取物的乙酸乙酯部分对粘虫(LeucaniaseparataWalker)有较好的非选择性拒食活性。从该部分分离得到11个化合物,通过NMR、MS等波谱分析确定它们的结构分别为4,5-二甲氧基-7-甲基香豆素(1)、4-甲氧基-5-甲基-6,7-二氧亚甲基香豆素(2)、4,7-二甲氧基-5-甲基香豆素(3)、齐墩果酸(4)、齐墩果酮酸(5)、齐墩果酸-3-O-β-D-吡喃木糖甙(6)、β-谷甾醇(7)、豆甾醇(8)、胡萝卜甙(9)、豆甾醇-3-O-β-D-吡喃葡萄糖甙(10)和过氧化麦角甾醇(11)。这些化学成分均为首次从该植物中分离得到,其中1和2为新化合物。  相似文献   

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牛至化学成分的研究   总被引:13,自引:0,他引:13  
从药用植物牛至(Origaanum vulgare L.)中分离并鉴定了8个化合物;乌素酸(1)、齐墩果酸(2)、原儿茶酸(3)、日本椴甙(4)、Sagittatoside A(5)、胡萝卜甙(6)、β-谷甾醇(7)、豆甾醇(8)。2~5为首次从该种植物中分离得到。  相似文献   

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秦艽中的环烯醚萜甙成分   总被引:22,自引:0,他引:22  
秦艽为著名传统中药。中青海西宁产秦艽的甲醇提取物的水溶性部分分离到1个新裂环烯醚萜甙,命名为秦艽甙A,2个已知的环烯醚萜甙即龙胆苦甙和哈马甙以及2个甾醇甙,胡萝卜甙和β-谷甾醇-3-O-龙胆糖甙。这些化合物的结构通过红外光谱、紫外光谱、核磁共振波谱(包括-维氢醇-3-O-龙胆糖甙。这些化合牧的结构通过红外光谱、紫外光谱、核磁共振波谱(包括一维氢谱、碳谱、氢-氢相关谱、碳-氢相关谱、远程碳-氢相关谱  相似文献   

5.
从单条草(LysimachiacandidaLindl)全草中分离出3个皂甙类化合物,经波谱分析并结合化学方法鉴定为:报春花素A3OβD吡喃木糖基(1→2)βD吡喃葡萄糖基(1→4)[βD吡喃葡萄糖基(1→2)]αL吡喃阿拉伯糖甙(1)、原报春花素A3OβD吡喃木糖基(1→2)βD吡喃葡萄糖基(1→4)[βD吡喃葡萄糖基(1→2)]αL吡喃阿拉伯糖甙(lysikoianoside,2)和α菠甾醇葡萄糖甙(3)。其中1是新化合物,命名为单条草甙(candidoside)。  相似文献   

6.
印楝愈伤组织的化学成分   总被引:13,自引:0,他引:13  
从印楝(Azadirachta indica A.Juss)的愈伤组织中,共分离鉴定出5个化合物,经理化性质和波谱分析分别确定为:柳杉酚⑴,豆甾醇⑵,软酯酸-1-甘油酯⑶,豆甾醇-3-O-β-D-吡喃葡萄糖甙⑷,豆甾醇-3-O-β-D-吡喃葡萄糖甙-6’-十六烷酸酯⑸。  相似文献   

7.
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   

8.
川明参根部的化学成分   总被引:4,自引:0,他引:4  
从我国特有的单种属药用植物川明参(Chuanminshen violaceum  Sheh et Shan)中分离出8个晶体,经理化性质和波谱分析分别鉴定为:5,8-二甲氧基补骨脂素(晶Ⅰ),5-异戊烯基-8甲氧基补骨脂素(晶Ⅱ), procyanidin A-2(晶Ⅲ),槲皮素-3-O-葡萄糖醛酸甙(晶Ⅳ),芦丁(晶Ⅴ),豆甾醇(晶Ⅵ),豆甾醇-葡萄糖甙(晶Ⅶ)及棕榈酸,硬脂酸的混合物(晶Ⅷ)。上述化合物均为首次从该植物中分离得到。  相似文献   

9.
滇黄芩中五个新的黄酮类配糖体   总被引:9,自引:0,他引:9  
从滇黄芩(Scutellaria amoena)根中分离到5个新的黄酮类配糖体。命名为滇黄芩甙甲-戊(amoeninsA-E)。经光谱分析,化学结构分别证明为:2’,4’,6’-三羟基二氢查耳酮4’-「O-β-D-半乳吡喃糖基(1→2)」-O-β-D-葡萄吡喃糖甙,5,7,2’-三羟基-6-甲氧基二氢黄酮7-O-β-D-葡萄吡喃糖醛酸甙,(顺式)-5,7,2’-三羟基二氢黄酮醇3-O-β-D-葡萄  相似文献   

10.
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   

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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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