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1.
采用MTT法检测纤毛婆婆纳(Veronica ciliata Fisch.)乙酸乙酯提取物(ethyl acetate extract,VEAE)对五种不同癌细胞(A549,Hela,U20S,MCF-7和SMMC-7721)的增殖抑制作用,筛选出对VEAE最敏感的细胞,并进一步运用DAPI染色、Annexin V/PI双染及荧光定量PCR(qRT-PCR)来探究其作用机制.MTT结果显示,VEAE对五种癌细胞的增殖均有抑制作用,并呈现时间和剂量的依赖效应,其中对MCF-7细胞的抑制作用最为显著,处理48h后其IC50达到最低,为63.42±0.19μg/mL;DAPI染色和Annexin V/PI双染结果发现,VEAE处理MCF-7细胞后,细胞皱缩变圆,凋亡细胞的数量增加,从对照组的5.00%上升到47.45%;qRT-PCR结果表明;VEAE处理MCF-7细胞后,凋亡基因Caspase-3,Caspase-9和Bax的表达上调,抗凋亡基因Bcl-2的表达下调.由此表明VEAE能抑制癌细胞的增殖,诱导细胞发生凋亡,其机制可能是通过调控与细胞凋亡相关基因的表达来实现.  相似文献   

2.
摘 要 目的:研究人参水溶性总蛋白对小鼠黑色素瘤细胞的增殖抑制作用及对Bcl-2/Bax表达的的影响。方法:1.MTT法测定人参水溶性总蛋白对黑色素瘤B16细胞株的增殖抑制率。2. RT-PCR(Real-time PCR)法检测Bcl-2、Bax基因的mRNA表达情况。3.Western blot测定凋亡蛋白Bcl-2和Bax的表达。结果:1.人参水溶性总蛋白对小鼠黑色素瘤B16细胞株有明显的增殖抑制作用,其抑制率随着加药浓度的增加而升高,并与加药浓度呈现一定的量效关系。2.随着人参水溶性总蛋白浓度的增高(0,100,500,1000ug/mL),RT-PCR检测的Bcl-2 mRNA相对表达量逐渐降低,Bax mRNA相对表达量逐渐升高,当加药浓度为1000ug/ml时,Bcl-2的相对表达量最低,为0.20±0.05,Bax的相对表达量最高,为16.83±0.07;与对照组相比,Bcl-2和Bax基因的相对表达量差异均有统计学意义(P<0.05)。3.经Western blot测定,各组Bcl-2蛋白的表达均低于对照组,各组Bax蛋白表达均高于对照组,且随着加药浓度的增加,Bcl-2蛋白表达量逐渐降低,Bax蛋白表达量逐渐升高。结论:人参水溶性总蛋白可以抑制小鼠黑色素瘤B16细胞株增殖,其分子机制可能与调控Bcl-2/Bax凋亡蛋白的表达有关。  相似文献   

3.
通过研究棉酚对宫颈癌Hela细胞的增殖抑制与凋亡作用,探讨棉酚的抗肿瘤作用机制。本实验采用MTY法检测棉酚对Hela细胞生长抑制率的影响;采用AO/EB双染色法、流式细胞仪进行细胞凋亡形态的观察和凋亡率的检测;免疫细胞化学法检测Bcl-2、Bcl—xL蛋白表达水平。研究结果表明棉酚对Hela细胞增殖有显著抑制作用,且呈剂量及时间依赖性;棉酚能明显诱导Hela细胞凋亡;棉酚降低Hela细胞内Bcl-2、Bcl—xL蛋白表达水平,表明棉酚可抑制宫颈癌Hela细胞的增殖并诱导细胞凋亡。  相似文献   

4.
采用MTT法研究了中华补血草根多酚提取物对HL-60细胞的抑增殖效果;AO/EB染色、DNA片段化检测和Annexin V-FITC流式细胞术等方法检测了多酚提取物对HL-60细胞诱导凋亡结果.Western blotting检测HL-60细胞株中Bcl-2、Bax蛋白的表达量.结果表明,中华补血草多酚能明显抑制HL-60细胞增殖,诱导HL-60细胞凋亡并具有质量浓度依赖性;Western blotting检测经药物处理的细胞内Bax蛋白显著升高,而Bcl-2蛋白表达水平明显降低,差异具有统计学意义(P<0.05),其凋亡机制可能与下调Bcl-2蛋白、上调Bax蛋白表达量相关.  相似文献   

5.
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.  相似文献   

6.
研究人参水溶性总蛋白对小鼠黑色素瘤细胞的增殖抑制作用及对Bcl-2/Bax表达的的影响:(1)MTT法测定人参水溶性总蛋白对黑色素瘤B16细胞株的增殖抑制率。(2)RT-PCR(Real-time PCR)法检测Bcl-2、Bax基因的mRNA表达情况。(3)Western blot测定凋亡蛋白Bcl-2和Bax的表达。结果:(1)人参水溶性总蛋白对小鼠黑色素瘤B16细胞株有明显的增殖抑制作用,其抑制率随着加药浓度的增加而升高;并与加药浓度呈现一定的量效关系。(2)随着人参水溶性总蛋白浓度的增高(0、100、500、1 000μg/m L),RT-PCR检测的Bcl-2 mRNA相对表达量逐渐降低,Bax mRNA相对表达量逐渐升高,当加药浓度为1 000μg/m L时,Bcl-2的相对表达量最低,为0.20±0.05;Bax的相对表达量最高,为16.83±0.07;与对照组相比,Bcl-2和Bax基因的相对表达量差异均有统计学意义(P0.05)。(3)经Western blot测定,各组Bcl-2蛋白的表达均低于对照组,各组Bax蛋白表达均高于对照组,且随着加药浓度的增加,Bcl-2蛋白表达量逐渐降低,Bax蛋白表达量逐渐升高。说明人参水溶性总蛋白可以抑制小鼠黑色素瘤B16细胞株增殖,其分子机制可能与调控Bcl-2/Bax凋亡蛋白的表达有关。  相似文献   

7.
目的 观察五味子酯甲(Schisantherin A,SCA)对人肝癌细胞(HepG2)增殖和凋亡的影响.方法 将体外培养的HepG2细胞分为空白对照组(CON)和SCA 25、50、100μmol/L 3个浓度组.给药48 h后,应用MTT法检测细胞存活率;应用Western blot法检测HepG2细胞Bcl-2、Bax和Caspase-3蛋白的表达水平;Hoechst染色观察上述各组细胞凋亡情况.结果 与CON组比较,SCA各组HepG2细胞存活率均显著降低(P<0.01);Bax及Caspase-3蛋白的表达水平显著增加(P<0.01),Bcl-2蛋白及Bcl-2/Bax比值表达显著降低(P<0.05或P<0.01);Hoechst染色显示HepG2细胞出现明显的核浓缩及核碎裂形态.结论 SCA能够抑制HepG2细胞增殖并促进其凋亡,该作用可为开发利用SCA的相关药物提供理论依据.  相似文献   

8.
为了探究松萝酸对肿瘤细胞增殖和凋亡的影响,体外培养人白血病细胞U937、人骨肉瘤细胞MG-63、人黑色素瘤细胞A375,用不同浓度的松萝酸分别作用于3种细胞24 h和48 h,用MTT法检测3种肿瘤细胞的增殖情况. Hoechst 33342染色观察U937经松萝酸处理后细胞形态的变化,Western Blot检测U937中凋亡相关蛋白的表达情况.结果发现,松萝酸对U937、A375和MG-63细胞增殖均有抑制作用,且均呈现出时间和剂量依赖性. 3种肿瘤细胞中,松萝酸对U937增殖的抑制效果最好.通过Hoechst 33342染色发现,随着松萝酸浓度的升高,凋亡的U937细胞数逐渐增多. U937细胞经松萝酸处理后,Bax蛋白的表达量增高,Bcl-2蛋白和Caspase-3蛋白的表达量降低,Bax蛋白表达量与Bcl-2蛋白表达量的比值增加.由此认为,松萝酸诱导的U937细胞凋亡与Caspase依赖性线粒体途径有关.  相似文献   

9.
以原位末端标记法 (TUNEL)检测凋亡细胞 ,以 SABC免疫组化法检测 Bcl- 2与 Bax基因的蛋白表达改变 .结果是卵巢异位组凋亡指数高 ,与正常对照组相比有极显著差异 ;Bcl- 2 /Bax显著低于对照组 .说明增殖期正常子宫内膜很少发生凋亡 ,卵巢内异症异位内膜凋亡明显 ;卵巢内异症异位内膜细胞的凋亡不受卵巢激素的影响 ,并与月经周期无关 .Bcl- 2 /Bax蛋白对其调控作用也较弱 .  相似文献   

10.
目的:探讨水飞蓟宾对胰腺癌As PC-1细胞的增殖抑制作用及其作用机制.方法:MTT法和克隆形成抑制实验观察水飞蓟宾对人胰腺癌As PC-1细胞的增殖抑制作用,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检测细胞周期及细胞凋亡相关蛋白的表达.结果:不同浓度的水飞蓟宾对胰腺癌As PC-1细胞的生长均有抑制作用,且呈剂量-效应和时间-效应关系(P0.05),水飞蓟宾作用于As PC-1细胞48、72 h的IC50浓度分别为224.20、87.25μmol/L;克隆形成抑制实验显示,随着水飞蓟宾浓度增加,As PC-1细胞克隆形成逐渐减少.细胞周期检测结果显示,随着水飞蓟宾浓度的增加,胰腺癌As PC-1细胞出现明显G1期阻滞;水飞蓟宾处理组细胞的周期蛋白Cyclin D1、Cyclin E2、Cyclin A、Cyclin B1表达下降,细胞周期蛋白激酶CDK4、CDK6表达不变,细胞周期素依赖性蛋白激酶抑制蛋白P15INK4B、P21WAF1/CIP1表达升高,与流式检测的结果相一致.不同浓度水飞蓟宾作用48 h后,出现明显的凋亡细胞群;同时发现Caspase-9、Caspase-3活化降解,Caspase3下游效应蛋白PARP出现切割条带.JNK蛋白表达增加并磷酸化活化,Bcl-2蛋白家族中抗凋亡蛋白Bcl-2、Bcl-x L、Mcl-1表达明显降低,促凋亡蛋白Bax表达基本不变,BH3-only蛋白Bclxs、Bid、Bim表达增加.结论:水飞蓟宾明显抑制胰腺癌细胞增殖,通过诱导P15INK4B、P21WAF1/CIP1表达阻滞细胞周期在G1期,并通过诱导JNK活化激活线粒体细胞凋亡途径,进而诱导胰腺癌As PC-1细胞凋亡.  相似文献   

11.
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   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
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   

14.
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   

15.
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   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
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   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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