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1.
从秃叶黄皮树叶子(Phellodendron chinensevar.glabriusculumSchneid)分离到7个化合物,经波谱解析鉴定为6-O-乙酰基黄柏苷(1),6-O-乙酰基二氢黄柏苷(2),(2R)-4′,5-二羟基-7-O-β-D-吡喃葡萄糖基-8-异戊烯基-二氢黄酮(3),黄柏苷(4),2-O-β-D-吡喃葡萄糖基-6-羟基-苯甲酸苄酯(5),柑橘素C(6),3-羰基齐墩果烷(7),其中化合物1~3,5~7为首次从秃叶黄皮树叶子中分离得到。  相似文献   

2.
抱茎苦荬菜水溶性成分的分离与结构鉴定   总被引:3,自引:0,他引:3  
从抱茎苦荬菜的水溶性成分分离得到5个化合物,根据理化性质和光谱数据分别鉴定为木犀草素-7-O-β-D-葡萄糖醛酸苷(1),木犀草素-7-O-β-D-葡萄糖1→2葡萄糖苷(2),芹菜素-7-O-β-D-葡萄糖醛酸苷(3),菊苣酸(4),(-)3,4-二羟基咖啡酰基酒石酸(5)。化合物3~5为首次从该植物中分离得到。  相似文献   

3.
藏药翁布的黄酮类化学成分研究   总被引:1,自引:1,他引:0  
从藏药翁布(Myricaria germanica)的60%丙酮提取物中分离得到了11个黄酮类化合物,利用光谱、波谱分析法鉴定其结构分别为:35,,4’-三羟基-73,’-二甲氧基黄酮(1),3,5,4’-三羟基-7-甲氧基黄酮(2),3,5,3’,4’-四羟基-7-甲氧基黄酮(3),35,7,-三羟基-4’-甲氧基黄酮(4),柽柳素(5),山柰酚(6),槲皮素-3-O-β-D-葡萄糖苷(7)5,,7,4’-三羟基-3-O-β-D-葡萄糖醛酸(8),5,7,3’4,’-四羟基-3-O-β-D-葡萄糖醛酸(9),槲皮苷(10)和阿福豆苷(11)。上述化合物均为首次从该植物中分离得到,其中化合物4、5、7~11为首次从水柏枝属植物中分离得到。  相似文献   

4.
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   

5.
鹿蹄草化学成分研究   总被引:1,自引:0,他引:1  
从鹿蹄草(Pyrola callianthaH.Andres)中分离得到11个化合物,经光谱分析确定其结构为(4R)-1-四氢萘酮(1),(4S)-1-四氢萘酮(2),夹竹桃麻素(3),没食子酸(4),3,4-二羟基苯甲酸(5),鹿蹄草素(6),5-羟甲基糠醛(7),金丝桃苷(8),2″-O-没食子酰基金丝桃苷(9),鹿蹄草苷B(10),4-羟基-2,7-二甲基萘基-1-O-β-D-吡喃葡萄糖苷(11)。其中化合物1,2,3,5,6,11为首次从该植物中分离得到,化合物7为首次从该属中分离得到。  相似文献   

6.
吊石苣苔中的化学成分   总被引:5,自引:0,他引:5  
新鲜吊石苣苔全草用70%丙酮水溶液组织破碎提取,然后经Diaion HP-20,Toyopearl HW-40,硅胶等柱色谱技术进行分离纯化得到8个化合物,经波谱分析鉴定为5,7-二羟基-6,8,4′-三甲氧基黄酮(1),丁香酸(2),邻苯二甲酸-双-(2-乙基己基)酯(3),5,7-二羟基-6,8,4′-三甲氧基黄酮醇(4),7-羟基-6,8,4′-三甲氧基-5-O--βD-葡萄糖黄酮苷(5),7-羟基-6,8,4′-三甲氧基-5-O-[-βD-葡萄糖-(1→6)]--βD-葡萄糖黄酮苷(6),4′,5-二羟基-7-甲氧基-6-C--βD-葡萄糖黄酮苷(7)和4′,5-二羟基-6,7-二甲氧基-8-C-β-D-葡萄糖黄酮苷(8)。除7-羟基-6,8,4′-三甲氧基-5-O--βD-葡萄糖黄酮苷和7-羟基-6,8,4′-三甲氧基-5-O-[β-D-葡萄糖-(1→6)]--βD-葡萄糖黄酮苷外,其余6个化合物均为首次从该植物中分离得到。  相似文献   

7.
对显脉獐牙菜(Swertia nervosa)的化学成分研究。采用系统溶剂提取,常规硅胶柱色谱和薄层色谱进行分离纯化,根据化合物的物理、化学性质,UV、IR、MS、1H NMR、13C NMR等波谱鉴定其结构。从显脉獐牙菜中分离得到10个化合物,分别鉴定为1,5,8-三羟基-3-甲氧基酮(1)、1,3,8-三羟基-5-甲氧基酮(2)、5,7,3',4'-四羟基黄酮(3)、3,5,7,3',4'-四羟基黄酮(4)、2-C-β-D-吡喃葡萄糖-1,3,6,7-四羟基酮(5)、獐牙菜苦苷(6)、当药苦酯苷(7)、羟基当药苦酯苷(8)、齐墩果酸(9)、胡萝卜苷(10),化合物3~5、7、8和10为首次从显脉獐牙菜中分离得到。  相似文献   

8.
从珍珠荚蒾(Viburnum foetidum var.ceanothoides)的枝叶中分离得到14个化合物,经鉴定分别为:白桦醇(1),熊果醇(2),β-谷甾醇(3),白桦脂酸(4),熊果酸(5),对羟基苯甲酸(6),4,4′-二羟基-a-古柯间二酸(7),反式对香豆酸(8),顺式对香豆酸(9),红花菜豆酸(10),原儿茶酸(11),胡萝卜苷(12),1-O-(6-O-α-L-rhamnopyranosyl-β-D-glucopyranosyl) -4-allylbenzene(13)和apigenin 7-O-α-L-rhamnopyranosyl(1″ ′→2″)-β-D-glucopyranoside (14).其中,化合物1、7、9、10和13为首次从荚蓬属中分离得到;所有化合物均首次从珍珠荚蓬中分离得到.  相似文献   

9.
广藿香大极性化学成分的研究   总被引:1,自引:0,他引:1  
从广藿香(Pogostemon cablin (Blance)Benth.)地上部分乙醇提取物的正丁醇萃取部位分离得到13个化合物.通过光谱和波谱分析,分别鉴定为:芹菜素(1)、3,5,4'-三羟基-7-甲氧基黄酮(2)、3,5-二羟基_4',7-二甲氧基黄酮(3)、Apigenin 7-galacturonide(4)、Apigenin 7-(O-methylghacuronide)(5),Luteolin 7-O-(6-O-methyl-β-D-glucuronopyranoside)(6),4',5-二羟基-3',7-二甲氧基二氢黄酮(7)、Quercetha-7-β-D-ghcoside(8),3,23-Dihydroxy-12-oleanen-28-oic acid(9)、Syringaresinol-β-D-glucoside(10),毛蕊花糖苷(11)、列当苷(12)、紫葳新苷(13),化合物2~13均为首次从该植物中分离得到.  相似文献   

10.
大管的化学成分研究   总被引:1,自引:0,他引:1  
从小芸木属植物大管茎皮部位共分离得到12个化合物,运用MS、1H NMR和13C NMR等波谱方法并结合文献对照分别鉴定为5-formyl-6,7-dimethoxycoumarin(1),isoscoploletin-β-D-glucoside(2),6-(trans-1-buten-3-only)-7-methoxycoumarin(3),6-羟基-7-甲氧基香豆素(4),microfalcatin isovalerate(5),小芸木宁(6),丁香苷(7),coniferin(8),methyl 2-O-β-D-glucopyranosylbenzoate(9),2-hydroxy-5-methoxy-trans-cinnamic acid(10),3,5-二甲氧基-4-羟基苯甲醛(11)和邻仲丁基苯酚(12)。其中化合物1为新的天然产物;除5和6外,其余化合物均首次从该植物中分离得到。  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   

16.
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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