流式细胞仪法检测4HPR诱导Hela细胞凋亡的百分率

目的：实验结果表明4HPR抑制Hela细胞生长的机理之一是诱导该细胞凋亡。本文用流式细胞仪检测不同浓度的4HPR作用不同时间Hela细胞凋亡的百分比及细胞周期变化。方法：体外细胞培养及流式细胞仪检测法。结果：2μg／m的4HPR作用24、48、72h后,Hela细胞的凋亡百分比分别为4.1％、6．6％、26％;4μg／ml的4HPR分别为5．1％、8．3％、28％、8μg／ml的4HPR分别为5．9％、6．2％、34％。细胞周期分布图中,G1细胞明显减少。结论：上述结果提示Hela细胞凋亡的百分比与4HPR的作用时间、作用浓度呈正相关。     

Abnormal pattern detected in fragile-X patients by pulsed-field gel electrophoresis.

The fragile-X syndrome is the most frequent inherited form of mental retardation, with an incidence of 1 in 1,500 males. It is characterized by the presence of a fragile site at Xq27.3 induced in vitro by folate deprivation or by inhibitors of deoxynucleotide synthesis. Its mode of inheritance is unusual for an X-linked trait, with incomplete penetrance in both males and females. Some phenotypically normal males transmit the mutation to all their daughters who rarely express any symptoms, but penetrance is high in sons and daughters of these carrier women. Genetic and physical mapping of the Xq27-q28 region has confirmed that the disease locus is located at or very near the fragile site. Hypotheses proposed to account for the abnormalities in the inheritance of the disease include sequence rearrangements by meiotic recombination or a mutation that affects reactivation of an inactive X chromosome during differentiation of female germ cells. To detect such rearrangements, or methylation changes that may reflect a locally inactive X chromosome, we used pulsed-field gel analysis of DNA from fragile-X patients with probes close to the fragile-X locus. The probe Do33 (DXS465) detected abnormal patterns in fragile-X patients, but not in normal controls or in non-expressing male transmitters.     

棒状杆菌ps1产生广谱抗真菌活性物质的初步研究

棒状杆菌psl能产生广谱抗真菌活性物质，对其活性物质的抗菌谱、产生条件和部分特性进行了初步研究。棒状杆菌psl产生的活性物质pschl对白色念珠菌、丝核菌、镰刀菌等多种真菌均有强烈抑制作用，并具有良好选择性。活性物质pschl耐热性好，pH改变对其活性影响较明显，酸性环境有利于其稳定但在碱性条件下容易失活。     

An anorexic lipid mediator regulated by feeding.

Oleylethanolamide (OEA) is a natural analogue of the endogenous cannabinoid anandamide. Like anandamide, OEA is produced in cells in a stimulus-dependent manner and is rapidly eliminated by enzymatic hydrolysis, suggesting a function in cellular signalling. However, OEA does not activate cannabinoid receptors and its biological functions are still unknown. Here we show that, in rats, food deprivation markedly reduces OEA biosynthesis in the small intestine. Administration of OEA causes a potent and persistent decrease in food intake and gain in body mass. This anorexic effect is behaviourally selective and is associated with the discrete activation of brain regions (the paraventricular hypothalamic nucleus and the nucleus of the solitary tract) involved in the control of satiety. OEA does not affect food intake when injected into the brain ventricles, and its anorexic actions are prevented when peripheral sensory fibres are removed by treatment with capsaicin. These results indicate that OEA is a lipid mediator involved in the peripheral regulation of feeding.     

基于流式细胞技术的两种槭属植物基因组大小测定

【目的】槭属植物具有重要的园林观赏价值和药用价值,开发应用前景广阔,但该属植物分子生物学及基因组学研究还相对匮乏,此次研究利用流式细胞仪技术对该属中鸡爪槭和元宝枫基因组大小进行测定,为后期槭属植物的细胞遗传学和基因组学研究奠定基础。【方法】以鸡爪槭(Acer palmatum)和元宝枫(A. truncatum)的嫩叶为材料,首次采用LB01解离液和碘化丙啶(PI)荧光染料,利用基因组大小已知的玉米(Zea mays L.)CE-777作为内标,建立适合于该两种材料的流式细胞术基因组大小测定方法。【结果】LB01解离液对测定样品与内标解离效果均较好,粒子清晰集中,无重叠峰且区分度良好,最后测得鸡爪槭的基因组1C含量为0.840 4 pg,元宝枫的基因组1C含量为0.756 0 pg。【结论】基于流式细胞仪技术,选取合适的样品处理方法,可成功测定鸡爪槭和元宝枫的基因组大小。该结果和方法可丰富槭属植物的基因库,为揭示该属植物的物种起源和进化提供重要依据,也为其后期的基因组测序工作奠定了重要基础。     

一种硬件辅助的H.263视频编码方案的实现

提出了一种新颖而实用的Ｈ．２６３视频编码方案，其采用了硬件辅助的方法并利用ＰＣＩ总线的高带宽来达到实时效果；给出了其硬件编码环路框图、具体的ＰＣＩ接口实现方案及软硬件总体实现方案。     

火箭炮随机振动起始扰动分析法

本文根据火箭发射装置随机振动的特性,给出了由火箭发射装置振动所引起的火箭弹起始扰动中间偏差φ_0的新估计法.理论分析与计算模拟说明了新估计法具有较高的精度,并且新估计法还能简化测试手段.     

GML文档结构聚类算法Clu-GML

提出了一种geography markup language(GML)文档结构聚类新算法CIu-GML,与其它相关算法不同,该算法在凝聚的层次聚类中引入代表树的计算,通过计算最大频繁Induced子树得到簇的代表树,通过对代表树的比较发现新的簇,并更新新簇的代表树来完成聚类,不仅减少了聚类的时间开销,而且为每个簇形成聚类描述.实验结果表明算法CIu-GML是有效的,且性能优于其它同类算法.     

1.5—4.5MeVα粒子引起Lu,Ta和Au L亚壳层电离的研究

以能量为１．５－４．５ＭｅＶ的α粒子轰击Ｌｕ，Ｔａ和Ａｕ靶，测得Ｌ亚壳层Ｘ射线产生截面，利用荧光产额和Ｃｏｓｔｅｒ－Ｋｒｏｎｉｇ跃迁几率等原子参数得到Ｌ亚壳层电离截面，将实验所得Ｌ亚壳层电离截面与ＥＣＰＳＳＲ预言值进行比较，对Ｌ１和Ｌ３亚壳层，理论值与实验结果符合较好。     

汉语中的性别歧视现象探析——由“总统先生”和“总统夫人”想到的

语言是社会的一面镜子,反映了特定社会的价值观念和民族思维方式.本文着重从汉语的造字语义、词汇组合、修辞手法和日常称谓等方面对语言中存在的性别偏见现象加以分析,并进一步揭示出这些现象背后的社会文化根源.     

美国《化学文摘》收录我校科技文献调查

我校研究人负发表的文献被美国《化学文摘》（CA）收录的篇数在1994～1998年间至上升趋势,从1994年的3篇,到1998年的11篇,说明我校化学化工领域的研究水平不断提高．事实表明,只要论文水平较高,无论在核心期刊或非核心期刊上发表均有可能被CA收录．     

应用生物技术发展罗汉果产业化的探讨

阐述了发展罗汉果产业化生产的重要性,指出了福建省引种栽培罗汉果存在的问题,介绍了应用生物技术研究脱毒罗汉果种苗快速繁殖的方法,并提出建立现代工厂化育苗中心(基地)的建议.     

An unusual feature revealed by the crystal structure at 2.2 A resolution of human transforming growth factor-beta 2.

Transforming growth factor type beta 2 (TGF-beta 2) is a member of an expanding family of growth factors that regulate proliferation and differentiation of many different cell types. TGF-beta 2 binds to various receptors, one of which was shown to be a serine/threonine kinase. TGF-beta 2 is involved in wound healing, bone formation and modulation of immune functions. We report here the crystal structure of TGF-beta 2 at 2.2 A resolution, which reveals a novel monomer fold and dimer association. The monomer consists of two antiparallel pairs of beta-strands forming a flat curved surface and a separate, long alpha-helix. The disulphide-rich core has one disulphide bone pointing through a ring formed by the sequence motifs Cys-Ala-Gly-Ala-Cys and Cys-Lys-Cys, which are themselves connected through the cysteines. Two monomers are connected through a single disulphide bridge and associate such that the helix of one subunit interacts with the concave beta-sheet surface of the other. Four exposed loop regions might determine receptor specificity. The structure provides a suitable model for the TGF-beta s and other members of the super-family and is the basis for the analysis of the TGF-beta 2 interactions with the receptor.