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1.
石香薷中化学成分的研究   总被引:13,自引:0,他引:13  
从石香薷(Mosla chinensis Maxim .)中分离到10 个化合物,经光谱分析、化学方法及与已知化合物对照,分别鉴定为:6-甲基三十三烷(1)、β-谷甾醇(2)、熊果酸(3)、5-羟基-6,7-二甲氧基黄酮(4)、5-羟基-6-甲基-7-O-β-D-吡喃木糖(3→1)-β-D-吡喃木糖双氢黄酮甙(5)、5,7-二羟基-4-甲氧基黄酮(6)、洋芹素(7)、山奈素-3-O-β-D-葡萄糖甙(8)、桑色素-7-O-β-D-葡萄糖甙(9)、鼠李柠檬素-3-O-β-D-芹糖(1→5)芹糖-4-O-β-D-葡萄糖甙(10)。其中,化合物5和10 为新化合物  相似文献   

2.
麻疯树根的化学成分研究   总被引:18,自引:0,他引:18  
从麻疯树(Jatropha curcas L.)的根中分离到13 个化合物,经理化常数和波谱鉴定(IR、1H-NMR、13C-NMR、EIMS和FABMS)分别为∶5α-豆甾烷-3,6-二酮(1)、川皮甙(2)、β-谷甾醇(3)、蒲公英脑(4)、2S-正二十四饱和脂肪酸甘油酯-1(5)、5-羟基-6,7-二甲氧基香豆素(6)、麻疯树酚酮A(7)、麻疯树酚酮B(8)、6-甲氧基-7-羟基香豆素(9)、caniojane (10)、3-羟基-4-甲氧基-苯甲醛(11)、3-甲氧基-4-羟基苯甲酸(12)和胡萝卜甙(13). 其中,化合物5 为未见报道的新化合物,化合物1、2、9、10、11、12 为首次从该植物中分得,10 为含有过氧基团的二萜化合物. 7 和8 为一对四环二萜的立体异构体,并在碱中相互转化  相似文献   

3.
中国特有植物白豆杉的化学成分研究   总被引:8,自引:0,他引:8  
从中国特有植物白豆杉(Pseudotaxuschienii(Cheng) Cheng)的叶中分得14 个单体成分,主要以波谱方法确定了它们的化学结构。其中13 个为已知化合物,分别为:2-guaiacylpropane-1,3-diol(1)、香草酸(2)、3-甲氧基-4-羟基肉桂酸(3)、3,5-二甲氧基苯酚(4)、taxicatin(5)、5-oxym altol(6)、槲皮素-3-鼠李糖甙(7)、(±)-儿茶素(8)、蜕皮素(9)、β-谷甾醇(10)、葡萄糖(11)、(±)-10-nonacosanol(12)和二十八酸(13)。除β-谷甾醇外,其余化合物均是首次从该植物中得到。其中,化合物1 和6 未曾从植物中直接得到过。另一单体成分经波谱和化学方法鉴定,初步推定为新化合物,命名为白豆杉内酯(pseudotaxlactone,14)。  相似文献   

4.
邱运平  陈秀珍  朱大元   《广西植物》1982,(4):213-215
<正> (山弄)岗通城虎Aristolochia longgangensis C.F.Liang.在前文我们曾报导从其根中分得结晶性单体(Ⅰ—Ⅺ),其中四个(Ⅰ、Ⅱ、Ⅲ、Ⅳ)经鉴定为尿囊素(Allantion)、马兜铃酸(Aristolochic acid)、马兜铃酸C(Aristolochic acid C)和马兜铃内酰胺-β-D-葡萄糖甙(Aristololactam-β-D-glucoside)。本文报导另外三个化合物(Ⅶ、Ⅴ、Ⅸ)的鉴定,它们分别为马兜铃内酰胺AⅡ(Aristololactam AⅡ),朱砂莲内酰胺  相似文献   

5.
从直距翟雀花(Delhinium orthocentrun Franch.)全草的甲醇提取物中分离得到了3个降二萜生物碱,通过NMR,MS等波谱分析将其结构鉴定为7,10-二羟基8,1、4,16三甲氧基19,20-二去氢乌头烷(7β,8β,14α,16β)(1),20-乙基-2,3-二去氢-6,10二羟基-7,8-二氧亚甲菜-1,14,16-三甲氧基乌头烷(1α,6β,14α,16β)(2)和翼北  相似文献   

6.
四川蜘蛛抱蛋的甾体皂甙   总被引:5,自引:0,他引:5  
从四川蜘蛛抱蛋(Aspidistra sichuanensis K。Y。Lang et Z。Y。Zhu)根状茎中分离得到三个甾体皂甙,经光谱和化学方法分别鉴定为22-甲氧基-5β-呋喃甾烷-1β,3β,4β,5β,26-五羟基26-O-β-D吡喃葡萄糖甙(1),蜘蛛抱蛋皂甙(2)和原蜘蛛抱蛋皂甙(3)。(1)是一个呋喃甾醇型单糖链的新皂甙,(3)是本植物的主要皂甙。  相似文献   

7.
用气相色谱-质谱联用法分析了小花琉璃草精油的化学成分,鉴定了茴香脑、爱草醚、小茴香酮、对-甲氧基-苯甲醚等64个化合物,并用气相色谱测定了精油中各成分的相对含量  相似文献   

8.
从马兜铃属植物寻骨风(Aristolochia mollisstma Hance)的茎叶中分离得10种结晶性成份。经鉴定为:马兜铃酸 A、香草酸、马兜铃酸 D、马兜铃内酰胺、6-甲氧基马兜铃内酰胺、棕榈酮、三十醇、β-谷甾醇、β-谷甾醇-D-葡萄糖甙和硬脂酸。动物试验表明,马兜铃酸 A 具有明显的抗早孕作用。  相似文献   

9.
云南永善产蜘蛛抱蛋的甾体成分   总被引:3,自引:0,他引:3  
从云南省永善县产的百合科植物蜘蛛抱蛋(Aspidistra elatior)根状茎中分离得到8个甾体化合物。其中6个为已知的甾体化合物,分别鉴定为(25S)-3β-hydroxy-spirost-5-ene 3-O-β-D-glucopyranosyl(1→)「β-D-xylopyranosyl(1→3)」-β-D-glucopyranosyl(1→4)-β-D-galactopyranoside  相似文献   

10.
紫玉盘中的新内酰胺   总被引:3,自引:0,他引:3  
余冬蕾  郭剑 《Acta Botanica Sinica》1999,41(10):1104-1107
从紫玉盘(UvariamicrocarpaChamp.exBenth.)的茎枝分离到7个生物碱,经光谱数据分析鉴定为紫玉盘内酰胺(uvarilactam,1)、马兜铃内酰胺AⅡ(2)、马兜铃内酰胺BⅠ(3)、马兜铃内酰胺BⅡ(4)、马兜铃内酰胺AⅠa(aristololactamAⅠa,5)、4,5_dioxodehydroasimilobine(6)和oxoanolobin(7)。1~5属于菲甲酸内酰胺类化合物,6~7是阿扑菲生物碱类,化合物3与4以混合物出现。其中1是新化合物,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   

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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   

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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