高通量检测大样本桑黄发酵液总黄酮含量方法的建立北大核心CSCD

建立了大样本的桑黄发酵液样品中总黄酮的高通量测定方法。通过L9（3^4）正交实验设计优化,确定了基于亚硝酸钠．硝酸铝比色法的微孔板检测方法,优化后总黄酮含量测定的最佳反应条件：5％亚硝酸钠30μL,10％硝酸铝30μL,10％氢氧化钠50μL,室温反应10min,检测波长为510nm。检测结果表明,针对大样本检测,该法稳定性高,平均回收率为100．7％,相对标准偏差为0．607％,线性范围为0—50μg／mL,线性相关系数r^2=0．9994。比较分析结果显示,和多种传统总黄酮测定方法相比,实验所建立的高通量测定方法检测大样本快速、准确、用药量小,且稳定性高。     

多孔板-MTT比色法测定植物抗菌成分对细菌的抑制活性

多孔板-MTT比色法测定植物抗菌成分对细菌抑制活性的步骤为：每孔加入浓度为10^6cfu／mL的供试菌液90灿,然后加入不同浓度的药液10μL,28℃暗培养24h后,每孔中加入5mg／mL的MTT溶液10μL,继续培养4h后加入10％二甲基亚砜100μL,振荡30min,在570nm处测定溶液的吸光值。采用以上方法,测定植物抗菌成分蓝桉醇对辣椒斑点病黄单胞菌（Xanthomonas vesicatoria）和枯草芽孢杆菌（Bacillus subtilis）的半抑制浓度（IC50）分别为0．158和0．395mg／mL,小檗碱对溶血葡萄球菌（Staphylococcus haemolyticus）的IC50为0．587mg／mL。结果表明,多孔板-MTT比色法能快速、微量地测定植物成分对细菌的抑制活性。     

高效液相色谱法测定羊痫疯丸中盐酸小檗碱含量

目的：建立高效液相色谱法测定羊痫疯丸中盐酸小檗碱含量的方法。方法：采用Agilent ZORBAX SB-C18（250mm×4．6mm,5μm）色谱柱,流动相：乙腈-0．05mol／L磷酸二氢钠溶液（用磷酸调节pH值至3）（25：75）,流速：1．0mL／min,检测波长264nm,柱温40℃。结果：线形范围是：盐酸小檗碱0．0446～1．1150μg,r=0．9998（n=5）。平均回收率为97．25％,RSD为3．14％。结论：方法简便、快速准确,重现性好。可作为羊痫疯丸的质量控制方法。     

泥胡菜中芦丁含量分析

建立高效液相色谱法测定泥胡菜中芦丁的方法,优化芦丁的提取工艺。使用Diamonsil（TM）C18柱,流动相：乙腈-0．4％磷酸溶液（20：80）,检测波长：255nm,流速：1ml／min,柱温：30℃。样品用50％乙醇超声提取30min提取率最高为0．166％;芦丁在0．1～2．0μg范围内与峰面积呈良好的线性关系（r=0．9994）,平均加样回收率99．3％（RSD=0．8％,n=5）。该方法准确、快速、重现性好,可作为控制泥胡菜质量的有效测定方法。     

甲醇营养型酵母高密度培养过程中甲醇和乙醇的GC快速检测

采用气相色谱法（GC）快速检测甲醇营养型酵母发酵液中的甲醇、乙醇含量,具有样品处理简便,测定时间较短,结果重视性好的特点。在1－10mg/mL范围内具有很好的线性关系。在毕赤酵母高密度表达发酵过程中应用此法对甲醇和乙醇进行实时监空,细胞终密度超过300g/L（干重）。本方法为甲醇营养型酵母工程菌的发酵中试工艺研究提供了重要 的发酵生化参数。     

野油菜黄单胞菌L4生产黄单胞菌多糖的适宜条件

研究了野油菜黄单胞L4生产黄单胞菌多糖的适宜培养基和培养条件。培养基组成(g／L)为：蔗糖40—50,铵盐1．0—1．25,酵母膏2．0-3.0,CACO,3.0,MgsO4·7H2O 0．25,Na2HPO4·12H2O 0.1,柠檬酸0．01—0．10,pH7．5。种龄为48小时以上。在30℃于旋转式摇床(200r／min)上培养3天,发酵液粘度高达14000-16000cp。用乙醇沉淀得多糖28g／L以上。     

AB-8树脂对珍珠菜总黄酮的吸附性能研究

目的：考察AB-8树脂对珍珠菜提取液中总黄酮的吸附、解吸附性能及影响因素。方法：采用紫外分光光度法测定总黄酮的含量,分别考察了样品液浓度、pH值和流速对AB-8树脂吸附珍珠菜总黄酮的影响,以及洗脱剂乙醇浓度和流速对解吸附效果的影响。结果：样品液总黄酮浓度10mg／mL、pH值5．07、流速1．0mL／min时,AB-8树脂对珍珠菜总黄酮的吸附效果较好;洗脱剂为70％乙醇,流速1．5mL／min时,洗脱完全,固体总黄酮含量较高。结论：在上述条件下,AB-8树脂可用于珍珠菜提取液中总黄酮的分离纯化。     

一种免受乙醇干扰的GOD的酶电极

将酶电极应用于发酵糖的测定时。与糖共存的乙醇常常会影响测糖的准确性,通过对葡萄糖氧化酶(GOD)电极的研究,探讨了乙醇对测糖酶电极测定影响,进而研制出抗干扰的GOD酶电极,若是GOD电极的酶膜通过夹心法制备．在乙醇含量为0．1％(V／V)时·即产生显著的影响,使测定结果偏大4．3%,且乙醇的影响随浓度的升高而增大,若用尼龙网固定GOD膜,GOD电极在测定20mmol／L和5mm01／L左右的葡萄糖溶液时,含量高达9％的乙醇仍未对测定产生显著的影响．表现出良好的不受乙醇干扰的特性,并且,该尼龙网GOD电极具有良好的重复性、稳定的响应活性及较长的保存期．     

固相萃取-高效液相色谱法测定沙苑子苷含量

目的：建立沙苑子总黄酮中沙苑子苷的含量测定方法。方法：用以氨基为固定相的固相萃取柱对沙苑子总黄酮进行纯化,洗去杂质后的洗脱液进高效液相色谱仪测定。色谱柱为VP—ODS（150mm×4．6mm,5um）,流动相为甲醇：1％HAC溶液（41：59）;流速1．2mL／min;检测波长266nm。结果：沙苑子苷在5—25μg／mL范围内呈良好的线性关系,加样回收率为102．5％,RSD2．3％。结论：本法灵敏、快速、准确,可用于测定沙苑子总黄酮中沙苑子苷的含量。     

气相色谱法测定发酵液中胆固醇的含量

气相色谱法测定了发酵液中胆固醇的含量。采用Rtx-1（100%二甲基聚硅氧烷）毛细管色谱柱、FID检测器进行分析测定。当胆固醇浓度在0～200μg/mL范围内与色谱峰面积呈良好线性关系（r=0.9981）。方法的平均回收率为99.38%,相对标准偏差为0.75%（n=8）,最低检出限可达到0.816μg/mL。气相色谱法作为发酵液中胆固醇含量的快速测定方法,具有试剂用量少、操作简单、结果准确等特点。     

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.