流式细胞术BrdU／DNA双染法测定云芝糖肽诱导的Molt-4细胞周期阻滞

目的：探究云芝糖）Ik（PSP）对人急性淋巴母细胞白血病Molt-4细胞周期的影响。方法：采用流式细胞术BrdU／DNA双染法获得各时相细胞分布状况和细胞周期的动力学参数。结果：0．1mg／mlPSP处理12h后,G2／M期细胞百分比由对照组的11．09％减少至3．69％。DNA合成时间由12．10h延长至108．40h。24h处理组中,S期细胞百分比由对照组的43.29％增加至67．26％,而G0／G1期和G2／M期细胞百分比均减少,G0／G1期细胞百分比由对照组的37．47％减少至27．43％,G2／M期细胞百分比由对照组的19．24％降低至5.31％。DNA合成时间更是由11．95h延长至114．52h。结论：PSP对人急性淋巴母细胞白血病Molt-4细胞周期的阻滞作用在于S期．该作用与DNA合成抑制有关。     

秋水仙素诱导细胞周期停滞

DNA含量检测是流式细胞仪最早且目前仍然是其最为广泛的应用之一．原理是用荧光物质标记细胞DNA,流式检测的荧光强度即代表细胞内DNA的多少,由于细胞在不同时期的DNA含量的不同,故可以将细胞周期分为二倍体期（G0／G1期）,四倍体期（G2／M期）和S期（处于二倍体和四倍体间的过渡期）,通常用荧光染料PI（碘化丙啶,水溶性,488nm激发）标记细胞,然后用流式细胞仪进行检测,根据荧光的强弱判断检测的细胞在周期中不同时期的分布。     

三苯氧胺对乳腺癌和宫颈癌细胞增殖的影响

目的：研究三苯氧胺(tamoxifen,TAM)对人乳腺癌Bcap-37和宫颈癌HeLa细胞增殖的影响并探讨其可能的机制。方法：采用细胞培养、细胞计数、MTT、流式细胞术和激光共聚焦显微镜技术。结果：TAM(10^-6mol／L)使Bcap-37细胞的生长曲线下移,使HeLa细胞的生长曲线上移。TAM(10^-8～10^-6mol／L)剂量依赖性的抑制Beap-37细胞的增殖,促进HeLa细胞的增殖作用。TAM(10^-6mol／L)使Bcap-37细胞发生凋亡,凋亡率达到97．5％,而使HeLa细胞周期由G1期加速向S期转化,G1期的DNA含量由对照组的55．5％下降到加药组的32．8％,S期的DNA含量由对照组的29．0％上升到加药组的49．4％。激光共聚焦检测到TAM(10^-6mol／L)可使Bcap-37细胞和HeLa细胞内的Ca^2 浓度显著升高。结论：TAM可以通过调节细胞周期各阶段DNA含量和胞内Ca^2 浓度水平,从而调节Bcap-37细胞和HeLa细胞的增殖活动,提示使用TAM治疗乳腺癌时可能会对子宫颈产生副作用。     

CD11b/DNA双参数流式细胞术检测HL-60细胞分化的细胞周期

目的采用双参数流式细胞术研究全反式维甲酸(alltransretinoidacid,ATRA)诱导人类急性早幼粒白血病细胞HL-60细胞分化的细胞周期。方法HL-60细胞经分化诱导剂ATRA(终浓度为1μmol/L)诱导不同时间点后,利用CD11b/DNA双参数流式细胞术同时检测分化细胞表面抗原CD11b的表达及分化细胞DNA含量。结果HL-60细胞经ATRA诱导后,细胞表面分化抗原CD11b表达明显升高,细胞阻滞于G0/G1期,且CD11b阳性细胞主要位于G0/G1期。结论CD11b/DNA双参数流式细胞术能简便,快速,直观地检测细胞分化的细胞周期。     

流式细胞术BrdU/DNA 双染法测定云芝糖肽 诱导的Molt-4 细胞周期阻滞

目的:探究云芝糖肽(PSP)对人急性淋巴母细胞白血病Molt-4细胞周期的影响。方法:采用流式细胞术BrdU/DNA双染法获得各时相细胞分布状况和细胞周期的动力学参数。结果:0.1 mg/mlPSP处理12 h后,G2/M期细胞百分比由对照组的11.09%减少至3.69%。DNA合成时间由12.10 h延长至108.40 h。24 h处理组中,S期细胞百分比由对照组的43.29%增加至67.26%,而G0/G1期和G2/M期细胞百分比均减少,G0/G1期细胞百分比由对照组的37.47%减少至27.43%,G2/M期细胞百分比由对照组的19.24%降低至5.31%。DNA合成时间更是由11.95 h延长至114.52 h。结论:PSP对人急性淋巴母细胞白血病Molt-4细胞周期的阻滞作用在于S期,该作用与DNA合成抑制有关。     

胍基丁胺对血清诱导大鼠肺动脉平滑肌细胞增殖的影响

目的：观察胍基丁胺对血清诱导大鼠肺动脉血管平滑肌细胞（PASMCs）增殖的影响。方法：采用组织块贴壁法原代培养大鼠PASMCs,取对数生长期PASMCs分对照组和胍基丁胺组,比色法测定细胞培养液中乳酸脱氢酶（LDH）活力。液闪计数仪测定^3H-TdR掺入量,流式细胞仪测定细胞周期,图像分析法测定增殖细胞核原含量（PCNA）作为细胞增殖的指标。结果：胍基丁胺对PASMCs培养液中LDH活力无明显影响;胍基丁胺可显著减少血清诱导增殖PASMCs的^3H-TdR掺入量和PCNA的含量（P〈0．01）,使G0／G1期细胞比例显著增加,G2／M期细胞比例显著减少（P〈0．01）。随着胍基丁胺浓度的增加,PASMCs ^3H—TdR掺入量也相应显著减少（P〈0.01）。结论：胍基丁胺对PASMCs不产生明显的细胞毒性作用;但可抑制血清培养大鼠PASMCs的增殖,这种抑制作用呈剂量依赖性。     

ALA—PDT对正常人角质形成细胞生物效应的实验研究

目的：探讨ALA—PDT抑制角质形成细胞（KC）增殖的可行性和最佳效果。方法：新鲜包皮组织经两次酶消化法进行KC分离与培养,分设对照组、单纯ALA组、单纯照光组及0．1mmol／L、0．6mmol／L、1．2mmol／L、1．8mmol／L、3．6mmol／LALA五个浓度组,经0．5h、1h、3h、5h四个避光孵育时间后PDT。酶标仪检测PDT后KC存活率、FCM检测KC中PpⅨ荧光强度,确定ALA最佳药物浓度和最佳用药时间;吖啶橙染色和Annexin V／PI双染法检测KC凋亡率和生长周期的影响。结果：0．6mmoL／LALA（用药1h）-PDT组为最佳药物浓度和最佳用药孵育时间,显示Pp Ⅸ荧光强度表达与KC凋亡率最高,能明显抑制S期与G2期的细胞增殖,使细胞增殖指数降至最低。结论：0．6mmol／LALA（用药孵育1h）-PDT能明显抑制KC增殖,更有效地促进正常KC凋亡。     

核因子-κB在HUVEC细胞凋亡信号通路中的作用

目的：探讨核因子-κB（NF-κB）在人脐静脉内皮细胞凋亡信号通路中的作用。方法：体外培养人脐静脉内皮细胞系（HUVEC）,实验分为正常对照组、AngⅡ组和Gliotoxin干预组。应用改良MTF法,观察0．01μmol／L、0．1μmol／L、μmol／L和10μmol／L4种浓度的AngⅡ在不同时间对HUVEC细胞活性的影响。应用DNA凝胶电泳和流式细胞术检测AngⅡ作用于细胞后引起细胞凋亡的情况。应用免疫细胞化学技术检测NF-κB p65的核移位,评价NF-KB活化情况。结果：10μmol／L AngⅡ作用于细胞24h时,细胞活性下降,DNA凝胶电泳和流式细胞结果提示细胞发生凋亡,凋亡细胞率明显高于正常对照组,差异具有统计学意义（P〈0．05）,0．1mg／L Gliotoxin可拮抗AngⅡ的细胞抑制活性作用;免疫细胞化学技术显示,HUVEC细胞经AugⅡ诱导后,NF-κB出现明显核移位现象,提示NF-κB发生活化;Gliotoxin明显抑制NF-κB活化,与AngⅡ组相比,差异有统计学意义（P〈0．05）。结论：①ArcⅡ可引起HU—VEC细胞发生凋亡;而NF-κB特异性抑制剂Ghotoxin能够拮抗AngⅡ对HUVEC细胞的作用;②NF-κB可能是AngⅡ调控HUVEC细胞生存／凋亡通路中的重要信号转导分子。     

原儿茶酸促进人脂肪干细胞体外增殖的研究

为了寻找能够促进干细胞增殖的药物,观察了中药益智仁（Alpinia oxyphylln）中提取的原儿茶酸对人脂肪干细胞体外增殖的影响,并对其作用机制进行了初步的探讨．人脂肪干细胞能在体外分化为神经元样细胞,并对凋亡的PC-12细胞起到保护作用．原儿茶酸能够促进人脂肪干细胞的增殖,且呈现明显的剂量依赖性和时间依赖性．流式细胞术检测细胞DNA含量的结果显示,原儿茶酸处理组细胞S期所占比例明显增加,其中,1．5mmol／L原儿茶酸处理组细胞S期所占比例与对照组相比增加2倍以上．同时,该组细胞G2／M期所占比例明显增加,G0／G1期所占比例明显下降．蛋白质免疫印迹结果显示,1．5mmol／L原儿茶酸处理组细胞周期素D1（cyclinD1）的表达明显升高．cyclin D1-siRNA转染显著抑制了原儿茶酸对人脂肪干细胞体外增殖的促进作用．流式细胞术检测细胞表面标志物,成骨诱导和脂肪诱导的结果显示,原儿茶酸处理后,人脂肪干细胞仍保持间充质干细胞多分化潜能的特性．上述结果提示,原儿茶酸有可能在人脂肪干细胞介导的干细胞移植治疗中发挥作用．     

DNA流式细胞术在植物遗传及育种中的应用

DNA流式细胞术是一种分析和测定分离细胞核DNA含量的方法。该方法的关键技术包括制备完整细胞核悬浮液、核酸荧光染料染色、根据相对荧光密度(DNA含量)对细胞核进行分类。由于样品制备及分析方便快捷,该技术已成为植物倍性鉴定、基因组大小测定、生殖途径鉴定等研究的重要工具。该文在对DNA流式细胞术基本原理简要介绍的基础上,对其在植物遗传和育种中的应用进行了综述。     

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.