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1.
目的:研究不同高温和姜黄素联合作用对肿瘤细胞的生长抑制作用.方法:37~43℃与0~40mol/L姜黄素联合作用4~16h后,MTT比色法检测细胞活性,流式细胞仪测定细胞周期时相变化.结果:高温作用后主要引起细胞凋亡和G0/G1期阻滞,姜黄素能抑制HeLa细胞的体外生长,呈时间与剂量依赖性,细胞周期阻滞于G0/G1期.联合作用后表现出了两者作用的双重特点.结论:应用高温和中药联合治疗可能是提高肿瘤治愈率、减少对正常组织细胞损害的有效方式之一.  相似文献   

2.
目的探讨姜黄素(curcumin)对人膀胱癌细胞系T24体外侵袭能力及其作用机制.方法以不同浓度的姜黄素作用于膀胱癌T24细胞,MTT法检测细胞增殖抑制率,Transwell法实验观察T24侵袭能力的变化,Western blot法检测MMP-2和VEGF蛋白表达的差异.结果姜黄素能有效抑制T24细胞的增殖,并抑制T24细胞的体外侵袭能力,呈时间-剂量依赖性(P0.05).20μmol/L和50μmol/L姜黄素作用细胞24 h后,MMP-2,VEGF蛋白的表达量下降(P0.05).结论姜黄素对T24细胞的增殖和侵袭能力有抑制作用,其机制可能与下调MMP-2和VEGF的蛋白表达有关.  相似文献   

3.
探讨吴茱萸碱对人胃癌SGC-7901细胞的生长抑制、诱导细胞凋亡的影响.采用MTT法测存活率;光镜观察细胞形态学改变;流式细胞术测细胞凋亡;流式细胞仪检测线粒体膜电位.结果显示,吴茱萸碱能抑制胃癌细胞SGC-7901的生长.MTT法测得吴茱萸碱的IC50为3.15μg/mL.在光镜下观察药物作用24 h的细胞生长密度逐渐变疏,细胞变小,表面起皱,高质量浓度组大部分细胞破碎.流式细胞仪检测,用20、10、5、2.5、1.25μg/mL质量浓度的吴茱萸碱作用48 h均出现亚二倍体凋亡峰,凋亡率分别为27.273%、24.206%、20.575%、19.520%、18.361%.流式细胞仪测线粒体膜电位,用质量浓度2.5、1.25、0.625、0.313、0.152μg/mL的吴茱萸碱作用48 h后线粒体膜电位显著提高.提示吴茱萸碱通过诱导胃癌细胞SGC-7901的凋亡,而达到抗肿瘤作用.  相似文献   

4.
观察阿霉素对人肝癌细胞株QGY-7701的凋亡诱导作用。实验用阿霉素处理QGY-7701细胞后,用台盼蓝拒染法检测细胞增殖活性;光镜、荧光显微镜、透射电镜观察细胞凋亡形态;DNA琼脂糖凝胶电泳技术观察分析细胞凋亡情况;流式细胞仪检测细胞凋亡率的变化。结果显示,阿霉素处理QGY-7701细胞后,出现了明显的凋亡现象,而且随着药物浓度的增加,细胞凋亡的趋势越明显。分析结果可知,阿霉素作用QGY-7701细胞48 h的IC50值为4.9μg/mL。流式细胞仪检测出阿霉素处理QGY-7701细胞的凋亡率逐渐上升。综上所述,阿霉素可以诱导QGY-7701细胞出现凋亡的现象。  相似文献   

5.
研究岩藻甾醇对人早幼粒白血病HL - 60细胞的生长及细胞凋亡的影响.采用MTT比色法测岩藻甾醇对HL - 60细胞增殖的抑制作用;用Hoechst33258染液染色,在荧光显微镜下观察细胞形态学改变;采用流式细胞术检测细胞周期分布和细胞的凋亡率;比色法检测caspase -9,caspase -3活性.岩藻甾醇能抑制...  相似文献   

6.
为探讨小分子化合物Linifanib和Tivozanib对肺癌细胞A549和H358增殖的影响,以不同浓度Linifanib和Tivozanib预处理细胞48 h,用MTT法检测了细胞存活率,并通过流式细胞仪检测了细胞周期和凋亡情况,用RT-PCR检测了肿瘤抑制因子P21的mRNA表达量.结果表明:Linfanib和Tivozanib能抑制肺癌细胞的增殖,呈现剂量依赖性.Linifanib能诱导细胞凋亡,同时引起细胞周期在G2/M期阻滞.Tivozanib主要引起细胞周期在G2/M期阻滞.Linifanib和Tivozanib均能引起A549和H358细胞中P21的mRNA表达量显著升高,说明Linifanib和Tivozanib能抑制肺癌细胞A549和H358的增殖.  相似文献   

7.
目的:研究黄芩苷(BA)抑制Jurkat T细胞(人T淋巴细胞白血病细胞株)的生长和诱导其凋亡的作用及机制。方法:以噻唑兰(MTT)比色法测定BA对细胞生长的抑制率;胞内[Ca2 ]i和线粒体跨膜电势(ΔΨm)分别用F luo-4/AM和D iOC6(3)荧光探针标记,流式细胞仪检测;PI染色流式细胞术分析细胞周期分布及凋亡率;凋亡细胞形态以Hoechst33342/PI染色后荧光显微镜观察。结果:BA明显抑制Jurkat细胞增殖(P<0.01),并呈时间、浓度依赖性;BA可浓度依赖的诱导Jurkat细胞[Ca2 ]i浓度上升、线粒体膜电势ΔΨm降低,将细胞周期阻滞在S期,凋亡率增加,荧光显微镜下可见经BA(100 mg/L)作用的细胞呈现典型的凋亡核固缩表现,胞核呈致密浓染的颗粒状荧光。结论:BA体外显著抑制Jurkat T细胞增殖及诱导其凋亡,其机制可能与胞内[Ca2 ]i及线粒体依赖的凋亡通路有关。  相似文献   

8.
研究姜黄素与阿霉素联合应用对人纤维肉瘤HT1080、人乳腺癌MCF-7、人肺癌A549细胞的增殖抑制作用及诱导肿瘤细胞凋亡的协同作用,探讨其抗肿瘤协同作用的机制,为临床寻找有效的化疗增敏剂提供实验依据和理论基础.MTT法测定细胞增殖抑制率,结果表明5μmol/L姜黄素与阿霉素联合用药对HT1080、MCF-7、A549细胞均表现出协同抗肿瘤作用;Hoechst 33258荧光染色观察A549细胞凋亡的形态学变化;Westernblot法检测A549细胞bcl-2蛋白的表达,结果表明姜黄素与阿霉素联合应用可显著诱导A549细胞发生凋亡,其协同抗肿瘤的机制可能与下调抑凋亡蛋白bcl-2表达有关.  相似文献   

9.
探究KLF4沉默与经不同作用浓度阿霉素处理诱导的DNA损伤对肝癌HepG2细胞增殖凋亡的影响及其作用机制.应用RNA干扰技术,采用siRNA转染HepG2细胞以沉默KLF4基因.采用MTT法检测KLF4沉默前后对HepG2细胞增殖的影响,使用流式细胞术检测KLF4沉默前后对HepG2细胞周期变化影响,应用Western blot法检测转染前后HepG2细胞中KLF4蛋白及细胞周期相关蛋白表达变化.Western blot检测到高浓度的阿霉素促进KLF4的表达,并且低浓度的阿霉素可使得细胞停滞在G2/M期,高浓度的阿霉素则使部分细胞凋亡(19.31%).将KLF4沉默后,发现细胞生长变缓,低浓度的阿霉素处理后,细胞随时间增加而出现更多的细胞凋亡;高浓度的阿霉素处理后,细胞数明显减少,更多的细胞发生凋亡(28.89%),且在KLF4沉默前后均发现低浓度阿霉素促进p53与p21表达,高浓度阿霉素抑制其表达.阿霉素诱导的DNA损伤可提高KLF4的表达,KLF4依赖于DNA损伤激活的p53促进p21的表达,进而引起G1/S期细胞周期阻滞.沉默KLF4与阿霉素诱导的DNA损伤可协同抑制肝癌细胞的增殖、促进凋亡,其在肝癌细胞 HepG2中扮演十分重要的角色.  相似文献   

10.
目的研究二烯丙基二硫(diallyl disulfide,DADS)诱导人急性髓性白血病细胞系HL-60细胞凋亡和对细胞周期的影响。方法采用MTT、流式细胞仪等方法检测DADS对HL-60的增殖抑制,诱导凋亡以及细胞周期分布的影响。结果20μΜDADS作用HL-60细胞48h,MTT显示DADS对HL-60细胞有明显的抑制增殖作用;流式细胞仪分析结果显示DADS对HL-60细胞有明显的G2/M期阻滞作用;用丫啶橙染色法观察到不同阶段的凋亡细胞形态学改变,且DADS呈时间依赖性诱导HL-60细胞凋亡。结论DADS引起HL-60细胞G2/M期阻滞并诱导凋亡可能是其抗肿瘤的机制之一。  相似文献   

11.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to  相似文献   

15.
Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications (up to 574.8 km/ h test speeds or 380 km/h commercial speeds) in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.  相似文献   

16.
17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.  相似文献   

19.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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