小前胡中香豆素类成分研究

本文对韩国植物新种小前胡(Angelica czernaeviaKita forma dentate Yook)的根部进行了化学成分研究,从中得到了7个香豆素类化合物,利用波谱方法分别鉴定为异欧前胡素(1),川白芷内酯(2),紫花前胡素(3),7-羟基香豆素(4),紫花前胡醇(5),紫花前胡苷元(6)和紫花前胡苷(7);同时采用高效液相色谱法对该植物的根、茎、叶和果实进行了主成分川白芷内酯(2)和紫花前胡素(3)定量分析。     

中药前胡核磁共振氢谱法鉴定

使用＾１Ｈ－ＮＭＲ法对１９种前胡乙醚提取物进行了测试和解析,其中９种前胡的化学成分未见报道。根据主要化学成分香豆素的类型,将含角型二氢吡喃香豆素的１０种前胡归入白花前胡类;含线型二氢吡喃香豆素或线型二氢呋喃香豆素的８种前胡归秋紫花前胡类。研究结果表明,＾１Ｈ－ＮＭＲ法是鉴别中药前胡的快速、简便而可靠的检测方法。     

马山前胡的香豆素

从马山前胡(Peucedanum mashanense Shan et Sheh)中分离得到4个化合物,鉴定为香豆素化合物白花前胡丙素[( )pareruptorin A],白花前胡丁素[( )anomalin],虎耳草素(pimpinellin)和β-谷甾醇(β-sitosterol)。     

俯卧前胡的化学成分

从伞形科植物俯卧前胡(Peucedanum decumbens Maxiam)的根中分离鉴定了13个成分,其中化合物(1)是一个新的二氢呋喃香豆素,经各项光谱测定,确定其结构为:顺式-2′-(1″-甲基,1″-千里光酰氧基-乙基)-3′-羟基-线型二氢呋喃香豆素,命名为俯卧前胡素(decumbensol)。     

细裂前胡的香豆素成分

细裂前胡Peucedanum macilentum Franch。(伞形科)是云南西部应用的前胡地方品种,从其根的乙醇提取物中经硅胶柱层析得到6个化合物,分别鉴定为香豆素类化合物:伞形花内酯(umbelliferone)(1),佛手柑内酯(bergapten)(2),laserpitin(3),异白花前胡丁素(anomalin)(4);其它化合物:阿魏酸(ferulic acid)(5),β-谷甾醇(β-sitosterol)。     

水飞蓟油—一种很有开发利用价值的植物油

水飞蓟[Silybum marianum(L)Gaertn.],又名水飞雉、乳蓟,为菊科[Compositae]水飞蓟属植物,原产于南欧和北非。水飞蓟属共两种,另一种为象牙蓟[Silybum eburneum Coss. et Dur.]。常见的水飞蓟品种有紫花水飞蓟与白花水飞蓟[Silybum inarianum Var. albiflorum];白花水飞蓟系水飞蓟(紫花)的变种。在国外水飞蓟自古代就作为药用植物,应用较广泛的是德国民间,主要用于治疗肝胆疾     

遮阳对白花前胡叶片光合特性的影响

为规范白花前胡(Peucedanum praerupterum)种植和提高产量,对不同光强下白花前胡的光合特性进行了研究.结果表明,与遮阳40％和60％相比,对照(CK)和遮阳20％的白花前胡叶片具有更高的最大电子传递速率[分别为247.129和266.866μmol/(m2·s)]和最大净光合速率[分别为25.621...     

泰山前胡化学成分的研究

泰山前胡(Peucedanum wawrii(Wolff)su.)为多年生草本,有镇咳,祛痰的功效有较多蕴藏量,但尚未加以利用现报道泰山前胡香豆素的研究结果。结晶 A,熔点138—140℃,分子式为 C_(24)H_(28)O_7,红外光谱提示有酯基、芳环、芳醚。质谱 m/z:M~ 428,核磁共振谱示有凯林(khellactone)母核,连结异戊草酸及当归酸。此结晶不溶于水,能溶于无水乙醇及氯仿等溶剂。经鉴定结晶 A 为白花前胡 E 素(3′-angeloyl-4′-isovaleryl-cis-khellactone)。     

紫花前胡的提取工艺优化研究

目的:采用多指标综合评分法结合响应面法优选紫花前胡香豆素类成分的最佳提取工艺参数.方法:通过HPLC检测紫花前胡中的化学成分伞形花内酯、紫花前胡苷、补骨脂素、花椒毒素和佛手柑内酯的含量,以综合评分值作为评价指标,并对液料比、甲醇浓度和超声时间进行考察,且在单因素试验基础上,运用Box-Behnken设计响应面法优化提取...     

前胡属（Peucedanum L.）血清分类学研究

利用琼脂板双扩散沉淀反应对我国前胡属（Peucedanum L.)13种2变种的叶片蛋白质进行了血清学分析,根据血清相似性将所分析的种类分成5个类群,其中石防风（p.terebinthaceum(Fisch)Fisch.ex Turcz.]刺尖前胡（p.elegans Komarov)和白花前胡（p.praeruptorum Dunn)各自为一类群,其余种类分别以华北前胡（p.harry-smithii Fedde ex Wolff)和华山前胡（p.ledebourielloides K.T.Fu)为代表分成二个类群,结合形态,地理等资料,分别讨论了各血清学类群的种间关系和分类学问题。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

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.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

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.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

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.     

肝癌中HBV和HCV基因和抗原的分布及意义

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     

Selection with two alleles and complete dominance

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.