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1.
从穿鞘菝葜(Smilax perfoliata Lour.)的95%乙醇提取物的乙酸乙酯萃取部分分离得到6个化合物,其中有一个新化合物smilglaside F(1).经过核磁共振、质谱、红外光谱及化学手段鉴定了它们的结构.5个已知化合物分别是:芦丁(2)、3′-甲醚芦丁(3)、cassiamin A(4)、cassiamin B(5)和1,2,3-trimethoxy-5-hydroxyphenol-1-O-β-D-glucopyranoside(6).其中化合物2、4~6是首次从该属植物分离得到.  相似文献   

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采用机械破碎法和果胶酶酶解法,使成熟番茄果实细胞内含物充分释放,上清液经D-101大孔树脂富集吸附后,再经一系列柱色谱分离得到6个化合物,根据其理化性质和波谱分析,分别鉴定为:芦丁(1)、槲皮素(2)、木犀草素(3)、番茄皂苷A(4)、豆甾醇(5)、熊果酸(6)。其中,化合物1、2、3、5、6为首次从该植物中分离得到。  相似文献   

3.
采用机械破碎法和果胶酶酶解法,使成熟番茄果实细胞内含物充分释放,上清液经D-101大孔树脂富集吸附后,再经一系列柱色谱分离得到6个化合物,根据其理化性质和波谱分析,分别鉴定为:芦丁(1)、槲皮素(2)、木犀草素(3)、番茄皂苷A(4)、豆甾醇(5)、熊果酸(6).其中,化合物1、2、3、5、6为首次从该植物中分离得到.  相似文献   

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从草果( Amomum tsao-ko) 果实的甲醇提取物中分离得到了9 个酚性化合物, 其中一个为新的糖基被酰化的酚性配糖体。用1D, 2D NMR 和MS 等现代波谱学方法鉴定为2-甲氧基-1 , 4-二苯酚-1-O - [6- O -(3-甲氧基-4-羟基苯甲酰基) ]-β-D-吡喃葡萄糖苷(1) 。8 个已知化合物分别为3′, 5′-二-C-β-D-吡喃葡萄糖基根皮素( 2)、芦丁(3) 、槲皮素-3- O-β-D-吡喃葡萄糖苷(4 ) 、邻苯三酚( 5 )、邻苯二酚( 6) 、对羟基苯甲酸( 7)、原儿茶酸(8) 和香草酸(9) 。化合物2 , 3 , 5 , 7~9 均为首次从草果果实中分离得到。  相似文献   

5.
从苦荞籽壳Tataricum husks中分离得到9个单体化合物,经理化常数及波谱数据分析鉴定其结构分别为:芦丁(rutin,1)、槲皮素(quercetin,2)、山奈酚(kaempferol,3)、山奈酚-3-O-芦丁糖苷(kaempferol-3-O-rutin-nos,4)、大黄素(emodin,5)、谷甾醇棕榈酸酯(β-sitosterol palmitate,6)、α-谷甾醇(β-sitosterol,7)、过氧化麦角甾醇(ergosterolperoxide,8)和胡萝卜苷(daucostero,9)。除芦丁和槲皮素外,其余化合物为首次从苦荞麦籽壳中分离得到。  相似文献   

6.
牛蒡根化学成分研究   总被引:1,自引:0,他引:1  
从牛蒡根95%乙醇提取液中分离得到6个化合物,通过理化性质和波谱学方法鉴定出5个化合物分别为牛蒡子苷(1)、山柰酚(2)、腺苷(3)、羟基茄碱(4)、spirosl-3-O-α-L-rhamnopyrannosyl-(1→4)-O-β-D-galactopyr-anosyl(5),其中化合物2~5为首次从该种植物中分离得到。  相似文献   

7.
藏药黑蕊虎耳草的化学成分   总被引:10,自引:1,他引:9  
从黑蕊虎耳草(Saxifraga melanocentra)地上部分的乙醇提取物中分离得到10个化合物,通过波谱分析并与有关对照品比较,将其结构鉴定为山奈酚(1),槲皮素(2),山奈酚-3-O-β-D-葡萄糖苷(黄芪苷)(3),槲皮素-3-O-β-D-葡萄糖苷(4),山奈酚-3-O-芦丁糖苷(5),芦丁(6),2″-O-没食子酰芦丁(7),岩白菜素(8),没食子酸(9)和没食子酸甲酯(10),除化合物2、6、8和10外,其余6个化合物均为首次从虎耳草属植物中得到。这些成分的鉴定为该植物的药效学研究提供了新的化学依据。  相似文献   

8.
应用多种色谱技术进行分离纯化,从刺五加果肉水提取物中分离得到10个化合物,经理化性质和波谱分析鉴定其结构分别为左旋芝麻脂素(1)、紫丁香树脂酚(2)、6,7-二甲氧基香豆素(3)、7-羟基-6-甲氧基香豆素(4)、儿茶酚(5)、芦丁(6)、12-羟基硬脂酸(7)、豆甾醇(8)、β-谷甾醇(9)和蔗糖(10)。化合物3、4、5、7和8为首次从该植物中分得,其中化合物7为新的天然产物。  相似文献   

9.
山豆根化学成分研究   总被引:22,自引:2,他引:20  
利用多种柱层析方法,从山豆根中分得5个化合物。经过理化及波谱分析,分别鉴定为L-广高丽槐素(1)、红车轴草苷(2)、槲皮素(3)、芦丁(4)和异鼠李素-3-芸香糖甙(5)。其中化合物3,5为首次从该植物中分离得到。关键词:山豆根;L-高丽槐素;红车轴草苷;槲皮素;芦丁;异鼠李素-3-芸香糖甙  相似文献   

10.
蓝桉果实中的脂溶性成分   总被引:2,自引:0,他引:2  
从蓝桉(Eucalyptus globulusLabill.)果实乙醇提取物的石油醚部位分离鉴定出6个化合物,通过理化和波谱分析结构鉴定为:5-羟基-4′,7-二甲氧基-6-甲基黄酮(1)、blumenol A(2)、蓝桉醇(3)、绿花白千层醇(4)、β-谷甾醇(5)、二十二烷酸(6),其中化合物1~4和化合物6系首次从该植物中分离得到,化合物1和2首次从桉属植物中分离得到.  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   

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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