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1.
湖北泽泻的HPLC分析及有效成分含量测定   总被引:1,自引:0,他引:1  
采用高效液相色谱方法,以乙腈和水(65?35)为流动相,图谱收集波长为210 nm。用指标成分24-乙酰泽泻醇A、23-乙酰泽泻醇B的标准品作回归曲线(利用浓度和峰面积的线性关系),对药店出售的片状干燥泽泻的含量进行测定和图谱分析,并与资料中展示的不同泽泻制品含量相比较,从而对泽泻的制作方法、有效成分含量的影响及泽泻质量进行评价,建立起成熟的质量评价的定量方法体系。  相似文献   

2.
泽泻中二个三萜新成分的研究Ⅱ   总被引:3,自引:1,他引:2  
继前文鉴定的七个泽泻醇类成分后 ,又从泽泻中分离、鉴定出六个三萜成分 ,其中 11 乙酰 2 5 脱水泽泻醇A(2 5 anhydroalisolA 11 acetate,Ⅳ )、2 4 乙酰 2 5 脱水泽泻醇A (2 5 anhydroalisolA 2 4 ac etate ,Ⅴ )为新化合物 ,新泽泻醇 (neoalisol,Ⅵ )为新天然产物 ,其它已知成分是泽泻醇A(alisolA ,Ⅰ )、2 4 乙酰泽泻醇A(alisolA 2 4 acetate ,Ⅱ )、2 5 脱水泽泻醇A(2 5 anhydroalisolA ,Ⅲ )。  相似文献   

3.
四川产泽泻中三萜成分的研究   总被引:13,自引:3,他引:10  
从四川产泽泻中分离出七个泽泻醇类成分,其中24-乙酰泽泻醇F为新确定的立体构型,其它已知成分为泽泻醇F、23-乙酰泽泻醇B、16-羟基-23-乙酰泽泻醇B、13β,17β-环氧泽泻醇B、23-乙酰泽泻醇C、泽泻醇C。  相似文献   

4.
崔大方 《植物研究》1992,12(4):369-371
本文发表了新疆泽泻属一新种,即小泽泻Alisma nanum D.F.Cui,sp.nov。  相似文献   

5.
福建泽泻元素分析及其属性判别研究   总被引:3,自引:0,他引:3  
利用电感耦合等离子体质谱(ICP-MS),对福建建瓯产大叶、小叶泽泻中17种元素的含量进行了测定,在此基础上,运用SAS软件的DISCRIM过程对两类泽泻样品进行了判别分析,取得了良好的分类判别结果,利用上述方法得到的泽泻元素含量分布图谱有可能为中药材指纹图谱的建立及其规范化种植提供新的途径。  相似文献   

6.
泽泻化学成分的研究   总被引:11,自引:1,他引:11  
从泽泻(Alisma orientalis(Sam)Juzep)块茎中分离出12个化合物,经理化性质和波谱分析,分别鉴定为:β-谷甾醇3-O-硬脂酸酯(β-sistosterol-3-O-stearate,1),正二十三烷(tricosane,2),β-俗甾醇(β-sitosterol,5),硬脂酸(stearic acid,6)1-硬脂酸甘油酯(glyeryl 1-stearate,7),胡萝卜甙6′-O-硬脂酸酯(daucosterol-6′-O-stearate,8),泽泻醇B单醋酸酯(alisol B monoacetate,9),大黄素(emodin,10),泽泻醇C单醋酸酯(alisol C monoacetate,11),环氧泽泻烯(alismoxide,12).化合物1,2,5,6,7和10为首次由该植物中获得,化合物12首次以结晶形式获得,化合物3和4的鉴定仍在进行。  相似文献   

7.
本文对湖北省三种泽泻属 Alisma L. 植物进行了核型分析和形态研究。 结果表明: 泽泻 A.plantago-aquatica L. 和东方泽泻1) A. orientale (Sam.) Juzep. 2n=2x=14,窄叶 泽泻 A.canaliculatum A.Br. Bouche 2n=6x=42。 其中东方泽泻的核型是未报道过的新 类型,这与前人所提出的该属植物核型为同型的结论不同,且泽泻和东方泽泻在形态方面亦有 很大差异,因而支持将泽泻和东方泽泻分立两种的观点。又结合前人的工作,讨论了该属植物 核型变异的三种式样。  相似文献   

8.
氮磷钾肥对地道药材建泽泻生长与品质的影响   总被引:2,自引:1,他引:1  
通过田间正交试验并结合室内HPLC分析,研究了氮、磷和钾素营养对建泽泻〔Alisma orientale(Sam.)Juzepcz.〕生长和品质的影响。结果表明,施用基肥对建泽泻生长前期的叶片数、株高、叶宽和叶长等农艺性状的影响均大于不施基肥处理;氮、磷和钾施用量对建泽泻产量均无显著影响,当施肥量为纯N 225.0 kg.hm-2、P2O5187.5 kg.hm-2和K2O 225.0 kg.hm-2,总施肥量为637.5 kg.hm-2时,产量最高;氮、磷和钾施用量对建泽泻块茎的粒重均无显著影响;磷的施用量对建泽泻指标性成分23-乙酰泽泻醇B含量有显著影响,而氮和钾均没有显著影响,且影响作用从高至低次序依次为P2O5、N、K2O。  相似文献   

9.
泽泻三萜成分的研究Ⅲ   总被引:1,自引:0,他引:1  
本文又从四川产泽泻中分离、鉴定了 5个三萜成分 ,其中alisolE 2 4 acetate(Ⅱ )、13 ,17 epoxyal isolA 2 4 acetate(Ⅳ )为新化合物 ,其它已知成分是alisolE 2 3 acetate(Ⅰ )、13β ,17β epoxyalisolA(Ⅲ )、11 deoxyalisolA(Ⅴ )。  相似文献   

10.
采用国标方法测定泽泻梗的营养成分,用化学比分法和氨基酸比值系数法对其蛋白质的营养价值进行评价。此外,还对泽泻梗粗提物抑制α-葡萄糖苷酶的活性进行了测定。结果表明:泽泻梗(每100 g干样)含粗蛋白26.10 g、粗脂肪2.20 g、总膳食纤维27.56 g、灰分8.70 g、多糖4.22 g、还原糖4.87 g、维生素C 406.30 mg、胡萝卜素380.00μg。泽泻梗蛋白质组成中必需氨基酸/总氨基酸(EAA/TAA)为39.54%、必需氨基酸/非必需氨基酸(EAA/NEAA)为60.46%,鲜味氨基酸占总氨基酸含量的40%以上;其第一限制性氨基酸为含硫氨基酸(蛋氨酸和胱氨酸)。浓度为500μg/m L的泽泻梗水提醇沉物、泽泻梗醇提物的α-葡萄糖苷酶抑制率分别为43.75%、39.90%。  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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