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1.
滇黄芩中五个新的黄酮类配糖体   总被引:9,自引:0,他引:9  
从滇黄芩(Scutellaria amoena)根中分离到5个新的黄酮类配糖体。命名为滇黄芩甙甲-戊(amoeninsA-E)。经光谱分析,化学结构分别证明为:2’,4’,6’-三羟基二氢查耳酮4’-「O-β-D-半乳吡喃糖基(1→2)」-O-β-D-葡萄吡喃糖甙,5,7,2’-三羟基-6-甲氧基二氢黄酮7-O-β-D-葡萄吡喃糖醛酸甙,(顺式)-5,7,2’-三羟基二氢黄酮醇3-O-β-D-葡萄  相似文献   

2.
山西甘草化学成分的研究   总被引:7,自引:1,他引:6  
本文报导了从山西甘草中分离出的八种化合物,经化学方法和光谱分析(UV,IR,MS,^1HNMR和^13C NMR)鉴定出其中六种化合物,1蔗糖(sucrose),Ⅱ4’5,7-三羟革-8-异然基黄酮(4’,5,7-Trithydroxy-8-prenyl-flavone);Ⅲ异芒柄花甙(Isoononin),Ⅳ,4‘,7-二羟基黄酮(4’-7-Dithydroxyflavone);Ⅳ(liquir  相似文献   

3.
云南血竭的化学成分及抗真菌活性   总被引:53,自引:0,他引:53  
云南血竭为剑叶龙血树(Dracaena cochinchinensis(Lour.)S.c.Chen)树脂,从中分离到5个芳香族化合物:对羟基苯甲酸乙酰(1),7,4^′-二羟基黄烷(2),7-羟基-4^′-甲氧基黄烷(3),7,4^′-二羟基黄酮(4)和loureirin A(5)以及1个甾体皂甙(6),并对其中3个酚性成分进行了抗真菌活性检测。另外,用薄层层析法对云南血竭、广西血竭、海南血竭及  相似文献   

4.
为了解苦槛蓝(Myoporum bontioides)的化学成分,采用色谱分离法从叶中分离得到11个化合物,分别鉴定为:5,7,3’-三羟基-4’-甲氧基黄酮(1)、3,5,7,4’-四羟基-3’-甲氧基黄酮(2)、5,7,4’-三羟基-3’,5’-二甲氧基黄酮(3)、木犀草素(4)、山奈酚(5)、鼠李黄素(6)、5,7-二羟基二氢黄酮(7)、7,4’-二羟基二氢黄酮(8)、5,7,3’,4’-四羟基二氢黄酮(9)、5-O-乙酰基-3,7,3’,4’-四羟基二氢黄酮(10)和7-甲氧基香橙素(11)。除化合物4、7、11之外,其他化合物均为首次从苦槛蓝叶中分离得到。菌丝生长速率法测试表明化合物4、7~9和11对荔枝霜疫霉菌具有较好的抑菌活性。  相似文献   

5.
小叶臭黄皮的黄酮苷甙成分   总被引:3,自引:0,他引:3  
从云南西双版纳的小叶臭黄皮(Clausena excavata Burm.f.)中分离到一个新黄酮甙,5,7,5′-三羟基-3′,4′-二甲氧基黄酮3-0-α-L-吡喃鼠李糖甙(1)和4个已知黄酮甙,分别为5,7,3′,5′-四羟基-4′-甲氧基黄酮3-O-α-L-吡喃鼠李糖甙(2),5,7,3′-三羟基-4′-甲氧基黄酮3-O-α-L-吡喃鼠李糖甙(3),5,7,4′-三羟基-3′,5′-二甲氧基黄酮3-O-α-L-吡喃鼠李糖甙(4),5,7,4′-三羟基黄桐3-O-α-L-吡喃鼠李糖甙(5)。根据HMQC、HMBC实验修正了化合物2-5C6和C8的位碳化学位移的归属。  相似文献   

6.
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   

7.
从钟花报春花Primula sikkmensis Hook.中分离得到5个化合物,通过波谱分析其结构分别鉴定为5-羟基黄酮(1),2-苯基色原酮(2),5,8-二羟基黄酮(3),2’-羟基黄酮(4),3’-羟基-黄酮-4’-O-β-D-吡喃葡萄糖苷(5)。其中化合物1~4首次从该属植物中分离得到,化合物5首次从该植物中分离得到,并首次对3的NMR数据进行了归属。  相似文献   

8.
林辉  常徽  糜漫天 《生物磁学》2009,(8):1416-1418,1474
目的:观察2’-羟基二氢黄酮诱导白血病细胞HL-60凋亡过程中胞内抗氧化酶活性的变化,并探讨其抗肿瘤作用机制。方法:采用CASY-TT亚流式细胞术测定2’-羟基二氢黄酮对HL-60细胞存活率的影响;Annexin V/PI双染流式细胞仪检测分析细胞凋亡变化;化学比色法测定2’-羟基二氢黄酮作用后,HL-60细胞胞内抗氧化酶SOD、CAT、GSH—Px的活性变化。结果:2’-羟基二氢黄酮显著降低HL-60细胞存活率,其作用呈剂量和时间依赖性;凋亡分析结果显示,20μM的2’一羟基二氢黄酮作用HL-60细胞后,细胞凋亡率逐渐升高,并在12h后显著高于作用前水平;酶活性检测表明,20μM2’一羟基二氢黄酮作用后,HL-60细胞胞内抗氧化酶SOD、CAT、GSH.Px活性均显著降低,脂质过氧化产物MDA含量显著升高。结论:2’-羟基二氢黄酮显著降低白血病HL广60细胞存活率并诱导细胞凋亡,其中伴随着胞内抗氧化酶活性的显著降低。  相似文献   

9.
藏药翁布的黄酮类化学成分研究   总被引:1,自引:1,他引:0  
从藏药翁布(Myricaria germanica)的60%丙酮提取物中分离得到了11个黄酮类化合物,利用光谱、波谱分析法鉴定其结构分别为:35,,4’-三羟基-73,’-二甲氧基黄酮(1),3,5,4’-三羟基-7-甲氧基黄酮(2),3,5,3’,4’-四羟基-7-甲氧基黄酮(3),35,7,-三羟基-4’-甲氧基黄酮(4),柽柳素(5),山柰酚(6),槲皮素-3-O-β-D-葡萄糖苷(7)5,,7,4’-三羟基-3-O-β-D-葡萄糖醛酸(8),5,7,3’4,’-四羟基-3-O-β-D-葡萄糖醛酸(9),槲皮苷(10)和阿福豆苷(11)。上述化合物均为首次从该植物中分离得到,其中化合物4、5、7~11为首次从水柏枝属植物中分离得到。  相似文献   

10.
圆穗蓼中的新黄酮甙成分   总被引:1,自引:0,他引:1  
从圆穗蓼(Polygonum sphaerostachyum Meisn.)中分离得到2个新黄酮甙,经光谱分析和化学方法鉴定为:3'-羟基-5,4'-二甲氧基-6,7-二氧亚甲基黄酮-3-O-「β-D-吡喃木糖基(1→6)」-β-D-吡喃葡萄糖甙⑴和5,4'-二甲氧基-3'-异丙烯基乙酰基-6,7-二氧亚甲基黄酮-3-O-「β-D-吡喃木糖基(1→6)-β-D-吡喃葡萄糖甙⑵,分别命名为圆穗蓼素A  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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