针芽肺衣的化学成分

从针芽肺衣(Lobaria isidiophora)中共得到9个化合物,分别鉴定为针肺晶(isidiphoin),斑点酸(stictic acid),降斑点酸(norstictic acid),隐斑点酸(cryptostictic acid),茶渍酸(lecanoric acid),网脊衣酸A、B(retigeric acid A, B)和苔色酸甲酯、乙酯(methyl, ethyl orsellinates)。其中针肺晶为一新的缩酚酮,根据光谱和化学分析,推定了其结构。     

四种药用地衣的化学成分

从四种药用地衣中分离鉴定了黑茶渍素(1),降斑点酸(2),8′-乙氧基-降斑点酸(3),(—)-placodiolic acid(4),松萝酸(5),珠光酸(6),伏勒米醇(7)和五个相应的单芳环衍生物:β-苔黑酚酸甲酯(8),赤星衣酸(9),赤星衣酸乙酯(10)。2-羟基-4-甲氧基-6-正戊基苯甲酸(11)和2,4-二羟基6-正戊基苯甲酸(12)等12个化合物。其中金丝带[Le-thariella zahlbruckneri(DR.)]中含1,4,8,和10金丝刷[Lethariella cladonioids(Nyl·)Krog.Syn.]中含1,2,3,8和9,雀石蕊[Cladonia stellaris(Opiz.)Pouzar & Vezda]中含1,5,6,11和12黑石耳[Dermatocarpon miniatum(L.)Mann.]中含7,4被鉴定为前人报道的桔黄色素(canarionic acid)。     

梅衣的化学成分

从梅衣中分离得到9个化合物,经光谱鉴定,它们分别为黑茶渍素、氯代黑茶渍素、茶渍衣酸、苔黑酚羧酸、苔黑酚羧酸乙酯、β-苔黑酚羧酸甲酯、柔扁枝衣酸、分歧扁枝衣酸及赤星衣酸甲酯,用气相色谱和色谱-质谱联用法,对梅衣精油和梅衣浸膏分别进行了定性、定量分析。梅衣浸膏中共鉴定了37个成分,主要为赤星衣酸乙酯,β-苔黑酚羧酸甲酯、苔黑酚羧酸乙酯等。梅衣精油鉴定了47个成分,未发现有特殊苔香香气的物质。     

金丝带缩酚酸类化学成分研究

对采自青海省的金丝带[Lethariella zahlbruckneri(Dr.)Krog.]的乙酸乙酯部分进行研究,采用硅胶柱色谱、半制备高效液相和重结晶技术进行分离纯化,通过1 H-NMR、13 C-NMR技术对化合物结构进行鉴定,结果共分离鉴定了5个化合物,包括:1个缩酚酸类:雪茶素(5);4个缩酚酸和缩酚酸环醚裂解产物:赤星衣酸甲酯(1),β-苔黑酚酸甲酯(2),苔色酸甲酯(3)和苔色酸乙酯(4)。其中化合物1、3、4、5均为首次从该植物中分得。     

中国珊瑚枝属地衣之新记录和稀有种

对福建武夷山地衣物种多样性研究,发现了一些珊瑚枝属地衣的中国新纪录和稀有类群。它们是东亚珊瑚枝细枝变种和东亚珊瑚枝矮枝变种(中国新记录种),侧顶果珊瑚枝、大珊瑚枝头状变种和疣珊瑚枝为稀有种。标本保藏于中国科学院微生物研究所菌物标本馆地衣标本室(HMAS-L),并对其进行了简明的描述和讨论。     

云南的牛皮叶属地衣

本文报道中国云南的6种牛皮叶地衣,其中裂边牛皮叶(Stieta ptaetextata为中国新记录种,柄扇牛皮叶(S.gracilis),双缘牛皮叶(S.duplolimbata)和缘裂牛皮叶(S.weigelii)为云南首次记载,用TLC方法测定了每种地衣的地衣物质,并发现平滑牛皮叶(S.nylanderiana)除含三苔色酸(gyrophoric acid)外,还含有伴三苔色酸(congyrophoric acid);长期以来一般被认为不产生地衣物质的缘裂牛皮叶含有一未知物质,其斑点处于C溶剂系统的Rf3区,C+黄色KC+红色。     

黑龙江省两种地衣植物化学成分研究

本文报道石蕊科的两种地衣植物的化学成分。我们从地衣植物林石蕊(Cladonia arbusculd),雀石蕊(Cladonia stellaris)中分离鉴定了松萝酸(Usnicacid)、黑茶渍素(Atranorin)、珠光酸(Perlatolic acid)和四个相应的单芳环衍生物:赤星衣酸(Haematornmic acid)、赤星衣酸乙酯(Uthyl haematommate)、2-羟基-4-甲氧基-6-正成基苯甲酸(2-hriroxy-4-methoxy-6-n-pentylbenzoic acid)、2,4-二羟基-6-正戊基苯甲酸(2.4-dihydroxy-6-n-pentylbenzoic acid)。上述资料,对开发利用这种植物提供了科学依据。     

绿槽枝衣的化学成分

从地衣绿槽枝衣( Sulcaria virens) 中分离得到一个新的亚油酸异丙叉衍生物, 通过波谱学方法包括2D-NMR 确定其化学结构为: 9, 10-O-异丙叉基- (12 Z)-十八碳烯酸(1) 。同时还得到其它12 个已知化合物:( 9 Z, 12 Z )-十八碳二烯酸(2), 扁枝衣二酸(3), ( R ) -松萝酸(4), 枕酸甲酯( 5), 黑茶渍素(6) , virensic acid ( 7), abieslactone (8), 3α-羟基羊毛甾-7, 24-二烯-26, 23 R-内酯(9), 蒲公英赛醇(10 ), 蒲公英赛酮 ( 11 ), (22 E , 24 R )-5α, 8α-过氧麦角甾-6, 22-二烯-3β-醇(12) 和2, 2′-四氢角鲨烯(13)。     

硬枝树花的化学成分及抗氧化研究

以梯度提取的方法对硬枝树花进行石油醚(30–60)、二氯甲烷、乙酸乙酯提取,浸膏经过色谱柱层析分离纯化得到6个单体化合物,分别为松萝酸(1)、黑茶溃素(2)、巴尔巴地衣酸(3)、去甲环萝酸(4)、地弗地衣酸(5)、藻纹苔酸(6),并且都是首次从硬枝树花中分离得到。通过对清除DPPH?和ABTS?+能力的测定,对这6个化合物体外抗氧化活性进行评价。结果表明:藻纹苔酸在检测浓度范围内的?DPPH的清除率和终浓度呈现一定的量效关系,在55μmol/L时,藻纹苔酸的清除率为57.05%(P0.01)。黑茶溃素、巴尔巴地衣酸、去甲环萝酸在13.75–55μmol/L检测浓度范围内的DPPH自由基清除率与终浓度呈量效关系。松萝酸对DPPH?的清除能力较强,在3.4375μmol/L及27.5μmol/L时,DPPH自由基清除率达到74.78%(P0.01)及74.82%(P0.01),接近对照组BHT浓度为55μmol/L的清除率。地弗地衣酸、藻纹苔酸、巴尔巴地衣酸的ABTS?+自由基清除率与终浓度呈现一定的量效关系,在浓度为55μmol/L时,地弗地衣酸ABTS?+自由基清除率为50.79%(P0.01),藻纹苔酸为44.53%(P0.01),巴尔巴地衣酸为44.34%(P0.01),在13.75–55μmol/L浓度范围内,黑茶溃素ABTS?+自由基的清除率随着浓度的增大而逐渐增大。硬枝树花中含有多样的苯骈呋喃类和缩酚酸类化合物及其衍生物,是具有开发利用潜力的抗氧化剂资源。     

两种地衣植物的化合物分析

本文报道石蕊科石蕊属的两种地衣植物的化学成分,我们从软石蕊(Cladonia mitis),石蕊(Cladonia rangiferina)中分离鉴定了五个化合物,它们分别是左旋和右旋松萝酸、黑茶浸素、原地衣硬酸、环萝酸、蛋氨酸乙酯;上述资料对开发利用该植物资源提供了科学依据。     

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.