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1.
红豆杉(Taxus chinensis (Pilger) Rehd.)中的非紫杉烷类化合物   总被引:6,自引:1,他引:5  
从红豆杉(Taxus chinensis(Pilger)Rehd.)树皮中分离到三个非萜类化合物,波同它们提吴茱次碱(rutaecarpine)(1)。山奈黄=-4'-甲醚(kaempferol-4'-methyl ether)(2)和谷甾醇(β-D-吡喃葡萄糖甙(sitosterryI-3-O-βglucoside)(3)。吴茱次碱是首次在红豆杉属植物中发现。  相似文献   

2.
中药韭子中一个新生物碱成分   总被引:1,自引:0,他引:1  
从百合科植物韭(Allium tuberosum Rottler)的种子分离并鉴定了7个化合物,1,2,3,4-tetrahydro-4-hydroxy-4-quinolin carboxylic aeid(1)(命名为韭子碱乙,Tuberosine B),7-hydroxy-2,5-dimethyl 4-H-1-Benzopyran-4-one(Ⅱ),Vernolie acid(Ⅲ),3-met  相似文献   

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白喉乌头中的新二萜生物碱   总被引:1,自引:0,他引:1  
通过柱层析和高效液相层析从白喉乌头(Aconitum leucostom um Worosch.)的根中分离得到4种二萜生物碱,通过各种光谱数据的解析鉴定了它们的结构,其中一种是新化合物,命名为喉乌碱(leu-costine,Ⅱ);其它为已知化合物leuconine (Ⅰ)、dehydroacosanine (Ⅲ)和sepaconitine (Ⅳ)。  相似文献   

4.
大花地不容中的生物碱   总被引:3,自引:0,他引:3  
大花地不容(StephaniamacranthaH.S.LoetM.Yang)系防己科千金藤属(Stepha-nia)一新种[1]。其化学成分未见报道。今从其块根中分得8种生物碱,经鉴定,主要为l-四氢巴马汀(l-tetrahydropalmatine,Ⅰ)和异紫堇定碱(isocorydine,Ⅱ),得率分别为0.83%和1.82%。其余为紫堇定碱(corydine,Ⅲ)、紫堇单酚碱(corydalmine,Ⅳ)、千金藤定碱(stephalidine,Ⅴ)、巴马汀碱(palmatine,Ⅵ)、紫…  相似文献   

5.
短距乌头根的两个新二萜生物碱   总被引:2,自引:0,他引:2  
从短距乌头(Aconitum brevicalcaratum Diels)的根分离到两个新的二萜生物碱:短距乌碱丁(acobretine D, Ⅰ)和短距乌碱戊(acobretine E, Ⅱ),通过光谱技术(IR, MS, 1H 和13C-NMR)和化学方法确定了它们的结构。短距乌碱丁最初以盐酸盐的形式分得,利用1H-1HCOSY 和13C-1H COSY 归属了其盐的各碳和氢的化学位移值  相似文献   

6.
Zhao XY  Jiang ZY  Peng JZ 《生理学报》2000,52(6):473-478
在麻醉大鼠侧脑室注射左旋一叶Qiu碱(L-Sec),记录动脉血压(AP)、心率(HR)及肾交感神经放电(RSND),观察前脑室周系统GABA能紧张性活动改变引起的心血管效应。结果如下:(1)L-Sec可引起RSND增加、AP升高和HR加快,并呈一定剂量-效应关系;但L-S盈余 于bicuculline(Bic)。(2)L-Sec既能拮抗muscimol(Mus),又能拮抗baclofen(Bac)  相似文献   

7.
光轴苎叶Ju的化学成分研究   总被引:1,自引:0,他引:1  
从光轴苎叶Ju地上部分甲醇浸膏中分得11个化合物,经波谱分析确定其结构分别为:β-谷旮醇(4),4-烯-6β-羟基-3豆甾烷酮(2),麦角甾醇过氧化物(3),α-软脂酸甘油酯(4),(E)-3,4-亚甲二氧基苯丙烯醛(5),胡椒碱(6),胡椒次碱(7),荜拔明宁碱(8),guineensine(9),cepharanoneA(10),cepharanoneB(1)。  相似文献   

8.
本文测定了数种蝙蝠葛碱衍生物对钙调素激活的人红细胞膜Ca^2+-Mg^2+-ATPase和的影响,结果表明,这些化合物对该酶都有不同程度的抑制作用,其机制表现为性抑制,过量的CaM能完全逆转这些化合物所引起的抑制。当Ca^2+-Mg^2+-ATPase被胰蛋白酶限制性酶解完全活化后,其活力不再受CaM激活,但仍被这些化合物所抑制。  相似文献   

9.
德钦红景天的化学成分   总被引:21,自引:1,他引:20  
从云南产德钦红景天Rhodiola atuntsuensis(Praeg.) Fu 的根及根茎中首次分离得到8 个化合物。根据各项光谱数据及化学反应鉴定其中一个新黄酮甙的结构为3 , 5 , 7 , 8 - 四羟基-黄酮4′- 氧- α- L- 鼠李糖吡喃甙, 命名为德钦红景天甙(rhodiolatuntoside, 2) , 另外7 个已知化合物分别是草质素- 8 - 甲醚(herbacetin - 8 - methylether,1) , 槲皮素(quercetin ,3) , 芦丁(rutin,4) , 酪醇(tyrosol,5) , 红景天甙(salidroside,6) , 没食子酸(gallic acid,7) 和β-谷甾醇( - sitosterol,8) 。  相似文献   

10.
膝瓣乌头中生物碱成分的研究   总被引:2,自引:0,他引:2  
从膝瓣乌头(Aconitum geniculatum)根中共分得14单体成分,我谱法分别鉴定为,黄草乌碱甲、丙(vilmorrianines,A,C)1和2、乌碱(yunnaconitine)3、南乌碱乙(AustroconitineB)4、印乌碱(indaconitine)5,8-乙酰-14-苯甲酰尼奥宁(8-acetyl-14-enzoyineoline)8、塔拉萨敏(talatizminie  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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