氯化锂对MGC803细胞增殖及细胞周期的影响

研究氯化锂(LiCl)在体外对MGC803胃癌细胞增殖及周期的影响,以不同浓度的LiCl作用MGC803细胞24 h后,采用四甲基偶氮唑盐(MTT)比色法检测各组细胞的增殖活性,利用流式细胞术进行细胞周期分析.结果:①不同浓度的LiCl(10、20、40 mmol/L)均对MGC803细胞具有抑制增殖的作用,这种增殖抑制作用呈剂量依赖关系.②随着LiCl浓度的升高,发生G2/M期阻滞,与正常对照组相比,差异具统计学意义.说明LiCl能抑制MGC803胃癌细胞增殖和导致G2/M期阻滞.     

升阳十一味丸对胃癌细胞凋亡及细胞周期的影响

研究复方蒙药升阳十一味丸对体外培养的人胃癌MGC—803细胞凋亡及细胞周期的影响。以不同浓度的蒙药处理MGC—803细胞,通过MTT法检测药物作用后细胞的增殖情况,并计算生长抑制率。利用倒置光学显微镜、Hochest33342/PI荧光染色、流式细胞术,研究蒙药诱导细胞凋亡的作用及对细胞周期的影响。结果蒙药能抑制MGC—803细胞的增殖,并具有良好的量效关系。2.5 mg/mL药物作用MGC—803细胞48 h后,光镜下可见核固缩、核碎裂等凋亡细胞形态学变化。流式细胞仪检测到"亚G1峰",细胞周期分析表明S期细胞较对照组增多,G2/M期细胞下降,阻滞于S期。说明蒙药升阳可明显抑制胃癌MGC—803细胞的增殖,并在一定浓度范围内诱导细胞凋亡,这可能是其发挥抗肿瘤的作用主要途径之一。     

抗氧化剂Isoverbascoside对MGC80-3细胞抗氧化酶活性和癌基因表达的影响

以苔酚蓝拒染法、核黄素-NBT还原法、DTNB还原法及RNA斑点杂交分析法分别对经不同浓度Isoverbascoside(Isov)处理的MGC80-3 细胞的生长速率、II期抗氧化酶(超氧化物歧化酶、谷胱甘肽过氧化物酶和过氧化氢酶)活性和N-ras、C-m yc及p53 基因表达作了检测.结果显示:经Isov处理后,细胞生长明显受抑;II期抗氧化酶活性较处理前明显上升;癌基因N-ras、C-m yc的表达较处理前下降,而抑癌基因p53 表达上升. 表明Isov 的抑癌作用与诱导II期抗氧化酶活性升高和癌基因表达改变有关     

阿霉素脂质体的制备及其活性的初步研究

用超声波脂质体制备法建立一种阿霉素脂质体的制备方法，并观察其体外对人肝癌细胞系n9101及人低分化胃癌MGC803细胞系的杀伤效力．对阿霉素脂质体溶液进行扫描，寻求最佳波长．用sephadex G50柱分离单纯阿霉素和阿霉素脂质体．苔盼蓝拒染法测定杀伤力．阿霉素脂质体在480nm处有最大吸收峰，测定阿霉素脂质体的包封率为99．39％．对n9l0l和MGC803两种细胞系的杀伤作用与单纯阿霉素相近，作用更持久．此法制备的脂质体包封率高，重现性好，简便易行，所制得的阿霉素脂质体具有高度的杀伤活性．     

新型吲哚类衍生物对人胃癌MGC-803细胞增殖的影响

为了深入研究吲哚类衍生物对胃癌细胞增殖的作用及其机制,本文研究了19种吲哚类衍生物对人胃癌MGC-803细胞增殖的抑制作用并进行了构效关系分析,最终筛选出结构全新且具有明显抗肿瘤活性的候选化合物16.进一步的研究发现:化合物16能诱导MGC-803细胞发生G_2/M期阻滞;同时,Annexin V/PI双染的结果表明化合物16能诱导MGC-803细胞的凋亡.     

去甲斑蝥素抑制胃癌MGC-803细胞生长并诱导其凋亡

目的:探讨去甲斑蝥素对胃癌MGC-803细胞的抑制作用及其可能的作用机制。方法:噻唑蓝（MTT）法及克隆形成抑制实验观察去甲斑蝥素对胃癌MGC-803细胞的生长抑制作用,碘化丙锭（propidium iodide,PI）单染色检测细胞周期改变,膜连蛋白-异硫氰酸荧光素（Annexin V-FITC/PI）双染流式细胞术检测细胞凋亡水平,Western blotting检测凋亡相关蛋白的表达。结果:去甲斑蝥素作用MGC-803细胞后,不同浓度的去甲斑蝥素对胃癌细胞的生长均有抑制作用,且呈剂量-效应关系（P<0.05）,去甲斑蝥素作用于胃癌MGC-803细胞48 h和72 h的IC₅₀浓度分别为69.92μmol/L和31.27μmol/L;与对照组相比随着去甲斑蝥素的浓度增加,细胞克隆逐渐减少;细胞周期检测结果显示,随着去甲斑蝥素浓度的增加,胃癌MGC-803细胞出现明显G2/M期阻滞;不同浓度去甲斑蝥素作用后,出现明显的凋亡细胞群;Western blotting检测结果显示,去甲斑蝥素处理组细胞的Bcl-2蛋白家族中抗凋亡蛋白Bcl-2、Bcl-xL、Mcl-1表达明显降低,促凋亡蛋白Bax表达基本不变。Casepase-9、Caspase-3活化降解,PARP蛋白出现切割条带。结论:去甲斑蝥素能够抑制胃癌MGC-803细胞生长,使细胞周期抑制在G2/M期,并通过线粒体凋亡途径诱导细胞发生凋亡。     

水飞蓟宾联合5-FU抑制胃癌MGC-803细胞增殖及机制

目的:研究水飞蓟宾联合5-氟尿嘧啶(5-FU)抑制胃癌MGC-803细胞增殖,探讨其协同增效作用及机制.方法:采用噻唑蓝(MTT)法检测不同浓度的水飞蓟宾对人胃癌MGC-803细胞,人正常肝L02细胞的增殖抑制作用,并计算IC20,IC50;采用IC20浓度的水飞蓟宾联合不同浓度的5-氟尿嘧啶,观察对人胃癌MGC-803细胞增殖抑制作用;水飞蓟宾单独或联合5-FU作用于胃癌MGC-803细胞,碘化丙锭(PI)单染色检测细胞周期改变,Annexin V-FITC/PI双染流式细胞术检测细胞凋亡水平,Western blotting检测细胞周期和凋亡相关蛋白的表达.结果:MTT法检测显示,水飞蓟宾对胃癌MGC-803细胞有增殖抑制作用,且呈剂量-效应关系,对人正常肝L02细胞增殖抑制作用较弱.水飞蓟宾作用于胃癌MGC-803细胞48 h的IC20、IC50浓度分别为144.6、214.7μmol/L;水飞蓟宾与不同浓度的5-氟尿嘧啶联合作用于MGC-803细胞48 h,可提高MGC-803细胞对5-氟尿嘧啶的敏感性,增敏5.73倍.流式结果显示,无论是单独使用水飞蓟宾、5-氟尿嘧啶还是水飞蓟宾与5-氟尿嘧啶联合使用都能使细胞抑制在G0/G1期和出现凋亡细胞群;Western blotting结果显示,水飞蓟宾与5-氟尿嘧啶联合使用,能使细胞的细胞周期相关蛋白P15表达升高,CDK6表达下降,Bcl-2蛋白家族中抗凋亡蛋白Bcl-2,Bcl-xL表达明显降低,促凋亡蛋白Bax表达基本不变,Casepase-9,Caspase-3活化降解.结论:水飞蓟宾提高胃癌MGC-803细胞对5-FU的敏感性,水飞蓟宾在联合5-FU之后能够使MGC-803细胞抑制在G0/G1期,并通过线粒体凋亡途径使细胞发生凋亡.     

多糖对人胃癌SGC7901细胞生长抑制

以培养的人胃癌SGC7901细胞为对象,研究了用多糖处理后培养细胞的变化特征.结果显示,多糖可以抑制人胃癌SGC7901细胞的增殖,并呈现出对剂量和时间的依赖性.用1.0×10-2g/mL的多糖处理培养细胞48h后,出现典型的形态学凋亡现象和明显的DNA片段化,细胞凋亡率达到40%左右.随着细胞凋亡的发生,BCL-2蛋白的表达下降,而BAX蛋白的表达上升.因此,结果表明多糖可以通过诱导细胞发生凋亡来抑制人胃癌SGC7901细胞的生长,从而达到治疗胃癌的目的.     

紫杉烷类PEG-PDLLA纳米粒的制备及其体外评价

采用乳化-溶剂蒸发法制备紫杉烷类PEG-PDLLA纳米粒,马尔文激光粒度仪测其粒径及Zeta电位;HPLC法测定纳米粒包封率和载药量;研究载药纳米粒在PBS中的释放动力学;初步评价载药纳米粒在MGC803、HeLa细胞中的摄取及细胞毒性。结果表明,通过包载形成的纳米粒的粒径为(13±1)nm,分布较集中。载体与药物的质量比在20∶1时,紫杉醇的均一性最好,卡巴他赛的包封率最高,达到88.77%。载药纳米粒具有较好的缓释作用,MGC803、HeLa细胞的存活率降低,与临床用注射剂效果相近。紫杉烷类PEG-PDLLA纳米粒的性质、释放、细胞抑瘤率都较好,可为开发紫杉烷类新型静脉注射制剂提供实验依据。     

S-腺苷酰-L-甲硫氨酸（SAM）对HL-60细胞生长与分化的影响

以甲基供体S－腺苷酰－L甲硫氨酸（SAM）作为分化诱导物,处理人急性早幼粒白血病HL－60细胞,导致细胞生长受到抑制,且表现出一定的范围的SAM浓度依赖性和时间依赖性,在10umol.L^-1最适浓度下,细胞分化指数（NBT阳性率）达到16％,中性粒细胞标志酶酸性磷酸酶活性增高,细胞出现的明显的分化特征性形态变化,说明SAM具有诱导HL－60细胞分化功能。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that