乳突拟耧斗菜中的一新二萜成分

从乳突拟耧斗菜(Paraquilegia anemoides)乙醇提取物的非碱部分中分得两个二萜类化合物:ent—考兰烷—16β,17—二醇和拟耧斗菜素(paraquilegin)。其中拟耧斗菜素是一新化合物,其结构经光谱解析和化学方法证明为ent—17—咖啡酰氧基-考兰烷—16B-醇。     

乳突拟耧斗菜中的一新二萜成分

从乳突拟耧斗菜(Paraquilegia)乙醇提取物的非碱部分中分得两个二萜类化合物：ent-考兰烷-16β，17-二醇和拟耧斗菜素(paraquilegin)。其中拟耧斗菜素是一新化合物，其结构经光谱解析和化学方法证明为ent-17-咖啡酰氧基-考兰烷-16B-醇。     

荷叶的化学成分研究

从荷叶(Folium Nelumbinis)的乙醇提取物中分离鉴定出13个化合物,分别为荷叶碱(nuciferine,1),鹅掌楸碱(liriodenine,2),2-羟基-1-甲氧基阿朴啡(2-hydfoxy-1-methoxyaporphine,3),原荷叶碱(pronuciferine,4),去氢莲碱(dehydroroemerine,5),去氢荷叶碱(dehydronuciferine,6),莲碱(roemerine,7),胡萝卜苷(daucosterol,8),β-谷甾醇(β-sitosterol,9),1-二十烷醇(1-icosanol,10),1-十一烷醇(1-undecanol,11),(2R,4S,4aS,8aS)-4,4a-环氧-4,4a-二氢食用西番莲素[(2R,4S,4aS,8aS)-4,4a-epoxy-4,4a-dihydroedulan,12]和邻二羟基苯酚(benzene-1,2-did,13).其中化合物10～13为首次从荷叶中分离得到.     

蓖麻提取物和淡紫拟青霉对南方根结线虫的防治作用

通过杀线活性测定及盆栽试验,研究了蓖麻提取物和淡紫拟青霉(Paecilomyces lilacinus)对南方根结线虫(Meloidogyne incognita)的杀线活性及防治效果.结果表明:蓖麻碱不影响淡紫拟青霉孢子的萌发.蓖麻碱和淡紫拟青霉均具有较强杀线活性,蓖麻碱处理对南方根结线虫的卵孵化抑制率和二龄幼虫死亡率分别达61.7%和59.2%,显著高于对照处理;蓖麻碱和孢子液复合处理接种南方根结线虫的番茄苗后,植株平均根结数为15±3,显著低于对照的平均根结数37±2,株高、鲜重和根长增长率分别比对照提高38.5%、44.0%和57.0%.说明蓖麻提取物和淡紫拟青霉能减轻线虫危害,对番茄南方根结线虫病控制效果明显.     

碱蓬内生真菌拟茎点霉菌次生代谢产物研究

利用固体大米培养基对一株碱蓬内生真菌拟茎点霉菌(Phomopsis chimonanthi)进行发酵培养,利用硅胶、凝胶柱层析法以及高效液相色谱等技术对该株真菌的次生代谢产物进行研究。通过质谱和核磁共振等现代波谱分析方法对其结构进行了鉴定。分离得到3个次生代谢产物,分别为:3S,22R,26-trihydroxy-8,24E-euphadien-11-one(1),3-hydroxy-3-phenylpropanoic acid(2)和3-hydroxy-3-(4-hydroxyphenyl)propanoic acid(3)。其中化合物1为首次从该株真菌中分离得到。     

HPLC-UV测定大鼠血浆中氧化槐定碱含量及其药代动力学研究

建立测定大鼠血浆中氧化槐定碱的体内分析方法,并考察其药代动力学参数。血浆样品以甲醇溶液沉淀,采用ZORBAX XDB-C18(150 mm×4.6 mm,4.0μm)色谱柱分离,流动相为乙腈-磷酸缓冲溶液(0.01 mol/L KH2PO4,H3PO4调p H 3.30)=4∶96(V/V),检测波长210 nm。血浆中氧化槐定碱在2.50~500.00μg/m L内线性较好(r=0.9971),提取回收率为77.3%~89.9%,日内、日间精密度RSD均小于10%。大鼠静脉注射50mg/kg和100 mg/kg氧化槐定碱后,其消除半衰期t1/2分别为(37.24±9.27)和(34.25±8.82)min,AUC分别为(1998.76±178.35)和(5130.62±1450.86)mg/L/min,Cmax分别为(89.53±10.47)和(247.35±112.02)mg/L。本文建立的方法简便、经济,可用于氧化槐定碱体内药代动力学分析。     

黄河口滨岸潮滩不同生境下翅碱蓬硫元素的季节变化

2008年5-11月, 对黄河口滨岸潮滩不同生境下翅碱蓬(Suaeda salsa)硫(S)的季节变化特征进行了研究。研究表明: 中潮滩翅碱蓬(JP1)和低潮滩翅碱蓬(JP2)各器官生物量均具有明显的季节变化特征, 总体表现为JP1 > JP2; JP1和JP2地上与地下部分比值的变化较为一致, 整体表现为JP2 > JP1; 二者枯落物量呈递增变化; JP1和JP2叶、茎和枯落物中的全硫(TS)含量在生长季波动变化明显, 整体呈先增后减变化, 而根中的TS含量在生长季呈递减变化, 符合指数衰减模型; 二者不同器官及枯落物的TS累积量和S累积速率(V_S)季节变化明显, JP1地上部分的TS累积量和V_S明显高于JP2, 且二者地上部分的TS累积量和V_S均明显高于地下; JP1和JP2不同部分的S分配比差异明显, 其中叶的分配比最高, 分别为(38.34 ± 16.19)%和(66.27 ± 12.09)%, 说明叶是翅碱蓬重要的S累积器官。结果显示, 翅碱蓬的生态学特性和其所处生境的水盐状况对JP1和JP2生物量、TS含量、累积量、累积速率、分配比均具有重要影响。     

拟螺距翠雀花中的新二萜生物碱

从拟螺距翠雀花的根中分离、鉴定了六个二萜生物碱成分,其中三个为已知成分,分别为methyllycaconitine(1)、ajacine(2)和delsemine(3);另三个为新二萜生物碱,分别命名为螺翠碱甲(bulleyanitine A)、螺翠碱乙(bulleyanitine B)和螺翠碱丙(bulleyanitine C),纤MS、IR、~1H NMR、~(13)C NMR及DEPT等光谱的解析证明其化学结构分别为(4)、(5)、(6)。     

双台河口翅碱蓬生长与根、茎、叶碳、氮的分配

生物个体生长过程是其同化作用和异化作用过程中物质和能量吸收、转运、储存、排出平衡的综合结果,体现了生物对其生存环境的适应。对采集于双台河口潮滩湿地的翅碱蓬(Suaeda heteroptera)进行株高和根、茎、叶碳、氮含量测定的结果显示,以AIC_C和adj-R~2为准则选择的翅碱蓬株高生长模拟方程为Logistic方程。采用多模型推断确定的双台河口翅碱蓬平均理论渐近株高H_∞为(38.11±2.59)cm。翅碱蓬根、茎、叶碳含量分别为(37.92±4.40)%、(39.98±3.12)%、(28.27±3.41)%;氮含量分别为(0.68±0.35)%、(0.94±0.31)%、(1.26±0.19)%。仅根碳、氮含量与株高间呈显著负相关生长关系。翅碱蓬根碳、氮相对含量分别为97.8±2.1、90.2±9.2,与株高(8.1—36.6 cm)相比,翅碱蓬根碳、氮积累可能受到了环境条件限制。     

辽河口滨海湿地CH4排放特征及其影响因素

采用静态箱-气相色谱法,于2016年6—11月连续观测辽河口芦苇湿地、翅碱蓬湿地和裸滩湿地的CH_4排放速率,同时测定温度、氧化还原电位(Eh)、pH值和电导率(EC)等相关环境因子的动态变化。结果表明,3种类型湿地的CH_4排放具有明显的季节变化特征,均呈先上升后下降趋势。芦苇湿地、翅碱蓬湿地(涨潮前)和裸滩湿地(涨潮前)CH_4排放通量变化范围分别为0.447—10.40、0.045—0.509 mg m~(-2) h~(-1)和0.016—0.593 mg m~(-2) h~(-1),观测期内排放通量均值相应为(3.699±3.679)、(0.165±0.156) mg m~(-2) h~(-1)和(0.198±0.191) mg m~(-2) h~(-1),不同类型湿地之间差异显著(P0.01),芦苇湿地裸滩湿地(涨潮前)翅碱蓬湿地(涨潮前)。涨潮过程中,翅碱蓬湿地和裸滩湿地的排放速率分别变化在0.009—0.353 mg m~(-2) h~(-1)和0.018—0.335 mg m~(-2) h~(-1),观测期间其排放速率均值分别为(0.119±0.132) mg m~(-2) h~(-1)和(0.131±0.103) mg m~(-2) h~(-1),明显低于涨潮前(P0.01)。不同湿地类型间CH_4排放通量与电导率(EC)呈显著负相关(P0.01)。研究结果表明,潮汐和电导率均为影响辽河口不同类型湿地中CH_4排放的关键因子。     

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.