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1.
华山松球果多糖对人早幼白血病细胞的诱导分化作用   总被引:1,自引:0,他引:1  
研究了华山松球果多糖对人早幼粒白血病细胞的诱导分化作用。HL-60细胞经20~50mg/L华山松球果多糖处理后,细胞形态有明显的变化,细胞增殖能力下降,细胞对NBT染料还原能力增强,给药4d,NBT阳性细胞率达75%,酸性磷酸酶活力明显增加,呈阳性反应。非特异性酯酶呈阴性反应,该实验结果表明,华山松球果多糖可诱导分化HL-60细胞沿粒系方向途径趋于成熟。  相似文献   

2.
nm23-H1基因与人早幼粒白血病细胞HL-60增殖的相关性分析   总被引:4,自引:0,他引:4  
目的探讨nm23-H1基因的表达与白血病细胞HL-60增殖之间的关系。方法:以25ng/mL阿糖胞苷处理HL-60细胞,MTT法测定细胞生长抑制率,NBT还原比色法判断细胞分化状况,RT-PCR检测nm23-H1基因表达的变化;构建nm23-H1基因的真核表达质粒pEGFP-N1-nm23-H1,转染HL-60细胞,通过细胞生长曲线和血清依赖性实验检测nm23-H1基因的过表达对HL-60细胞生长的影响。结果:小剂量Ara-C对HL-60细胞的生长呈时间依赖性抑制,作用4d后细胞NBT还原能力增强且nm23-H1基因的表达下调;转染nm23-H1基因的HL-60细胞生长加快、血清依赖性下降。结论:Ara-C对HL-60细胞增殖的抑制作用与下调nm23-H1基因的表达有-定关系;nm23-H1基因在HL-60细胞中的过表达有促细胞增殖的作用,即增高了HL-60细胞的恶性程度。  相似文献   

3.
目的:探讨针对bcl-2mRNA蛋白编码区的反义寡核苷酸对HL-60细胞bcl-2蛋白表达和凋亡的作用。方法:应用台盼蓝拒染法和流式细胞仪检测HL-60细胞的活性和bcl-2蛋白表达和细胞凋亡的情况。结果:10μmol/L和20μmol/L的反义寡核苷酸能抑制HL-60细胞bcl-2蛋白表达和诱导细胞调亡,并且针对bcl-2mRNA蛋白编码区的反义寡核苷酸比针对bcl-2mRNA翻译起始区的反义寡核苷酸作用更强。结论:针对bcl-2mRNA蛋白编码区的反义寡核苷酸能抑制HL-60细胞bcl-2蛋白表达和诱导细胞调亡。  相似文献   

4.
利用MTT法、台盼蓝排染法、Hoechst33258荧光染色法、瑞氏-姬姆萨染色法以及单细胞凝胶电泳法检测了三氧化二砷(As2O3)单独作用及联合Trolox后对人早幼粒白血病细胞HL-60的增殖抑制、凋亡诱导作用及其DNA损伤作用.结果表明,1μmol.L-1As2O3作用即可抑制HL-60细胞的增殖,联合100μmol.L-1Trolox对HL-60细胞增殖抑制作用较As2O3单独作用时明显增强.高浓度的As2O3(4μmol.L-1)作用24h可引起HL-60细胞的凋亡,与Trolox联合作用,在低浓度(1μmol.L-1)下即可引起细胞凋亡.联合100μmol.L-1Trolox可以显著增强As2O3引起的HL-60细胞的DNA损伤.这种损伤可能导致细胞周期阻滞,从而在生长曲线中体现出对HL-60细胞的增殖抑制作用.  相似文献   

5.
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。  相似文献   

6.
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   

7.
利用倒置显微镜观察法、台盼蓝排染法、Hoechst33258荧光染色法、DNA ladder电泳以及流式细胞分析技术,检测了从甘肃产异叶败酱(Patrinia heterophylla Bunge.)中分离得到的三萜化合物常春藤皂苷元(HG)对人早幼粒白血病细胞HL-60的增殖抑制、周期阻滞及凋亡诱导作用.结果表明,常春藤皂苷元在较低浓度(10~40 μmol·L-1)条件下,时HL-60细胞增殖具有良好的抑制作用;在较高浓度(40~50μmol·L-1)条件下,对HL-60细胞具有致死作用;同时,常眷藤皂苷元对HL-60细胞的G1期阻滞和凋亡诱导作用极可能是其实现增殖抑制和致死作用的主要途径.  相似文献   

8.
苯胺类毒物(aniline poison)是一类常用化工原料和环境污染物,通过食物或饮水污染进入体内后能够干扰人体正常内分泌系统(endocrinium)稳态,影响细胞遗传物质的稳定最终导致细胞DNA突变增加癌变或畸变的风险。最近的研究表明,苯胺类毒物还有可能影响恶性肿瘤的治疗效果。选取代表性的三个苯胺类毒物:对苯二胺(p-phenylene diamine,p-PDA)、间苯二胺(m-phenylene diamine,m-PDA)、邻苯二胺(o-phenylene diamine,o-PDA),考察其在非小细胞肺癌(non-small cell lung cancer,NSCLC)中诱导肺耐药蛋白(human lung resistance protein,LRP)表达及其可能的分子机制。培养NSCLC细胞系A549,使用系列浓度梯度的对苯二胺(p-phenylene diamine,p-PDA)、间苯二胺(m-phenylene diamine,m-PDA)、邻苯二胺(o-phenylene diamine,o-PDA)处理细胞后,使用实时荧光定量PCR(q PCR)检测LRP的mRNA表达;蛋白印记实验(Western bolt,WB)检测LRP的蛋白表达;进一步使用芳香烃受体(aryl hydrocarbon receptor,AhR)的小干扰RNA(siRNA)抑制A549细胞中AHR的表达,确定对苯二胺、间苯二胺、邻苯二胺对LRP的诱导作用是否依赖于AhR;在此基础上,使用对苯二胺、间苯二胺、邻苯二胺预处理A549细胞后,再分别使用抗肿瘤药物吉非替尼(Gefitinib)、吉西他滨(Gemcitabine)处理A549细胞,利用MTT实验检测上述抗肿瘤药物对A549细胞存活的抑制率(inhibitory rate,IR),并计算药物作用的半数抑制率(IC50值)。q PCR实验与WB实验结果显示,对苯二胺、间苯二胺、邻苯二胺刺激A549细胞能够剂量依赖地诱导LRP的mRNA、蛋白表达水平。干扰AhR表达后,该三种苯胺类毒物不能诱导LRP的mRNA与蛋白表达。MTT实验结果表明,对苯二胺、间苯二胺、邻苯二胺能够下调抗肿瘤药物吉非替尼、吉西他滨对A549细胞的杀伤作用:吉非替尼作用于A549细胞的IC50值从(1.20±0.25)μmol/L上调为(5.67±0.44)μmol/L、(6.07±0.30)μmol/L与(7.51±0.28)μmol/L,其耐药指数(resistance folds)分别为4.73、5.06与6.26;吉西他滨作用于A549细胞的IC_(50)值从(0.44±0.10)μmol/L上调至(1.55±0.25)μmol/L、(1.88±0.19)μmol/L与(2.33±0.40)μmol/L,其耐药指数分别为3.52、4.27与5.30。3种代表性苯胺类毒物能够在肺癌细胞中通过AhR诱导LRP表达,并且能够引起A549对抗肿瘤药物耐受。  相似文献   

9.
D-核糖发酵液离心洗涤得菌体,采用超声波破碎(在40kW下,工作4s,间歇4s,破碎90次),制备无细胞抽提液.取无细胞抽提液80μL及100μmol/L葡萄糖、4μmol/LNADP、0.6mmol/LTris-HCl(pH=6.8)、10μmol/LMnSO4溶液各1mL,在37℃下保温10min,测定A340num的值,对比NADPH标准曲线,测定D-葡萄糖脱氢酶的酶含量.根据测定的时间及酶蛋白的含量,从而确定D-葡萄糖脱氢酶的酶活力的测定方法.  相似文献   

10.
背景:苯胺类毒物(aniline poison)是一类常用化工原料和环境污染物,通过食物或饮水污染进入体内后能够干扰人体正常内分泌系统(endocrinium)稳态、影响细胞遗传物质的稳定最终导致细胞DNA突变增加癌变或畸变的风险。最近的研究表明,苯胺类毒物还有可能影响恶性肿瘤的治疗效果。目的:选取代表性的三个苯胺类毒物:对苯二胺(p-phenylene diamine, p-PDA)、间苯二胺(m-phenylene diamine, m-PDA)、邻苯二胺(o-phenylene diamine, o-PDA),考察其在非小细胞肺癌(non-small cell lung cancer, NSCLC)中诱导肺耐药蛋白(human lung resistance protein, LRP)表达及其可能的分子机制。方法:培养NSCLC细胞系A549,使用系列浓度梯度的对苯二胺(p-phenylene diamine, p-PDA)、间苯二胺(m-phenylene diamine, m-PDA)、邻苯二胺(o-phenylene diamine, o-PDA)处理细胞后,使用实时荧光定量PCR(qPCR)检测LRP的mRNA表达、蛋白印记实验(Western bolt, WB)检测LRP的蛋白表达;进一步使用芳香烃受体(aryl hydrocarbon receptor, AhR)的小干扰RNA(siRNA)抑制A549细胞中AHR的表达,确定对苯二胺、间苯二胺、邻苯二胺对LRP的诱导作用是否依赖于AhR;在此基础上,使用对苯二胺、间苯二胺、邻苯二胺预处理A549细胞后,再分别使用抗肿瘤药物吉非替尼(Gefitinib)、吉西他滨(Gemcitabine)处理A549细胞,利用MTT实验检测上述抗肿瘤药物对A549细胞存活的抑制率(inhibitory rate, IR),并计算药物作用的半数抑制率(IC50值)。结果:qPCR实验与WB实验结果显示,对苯二胺、间苯二胺、邻苯二胺刺激A549细胞能够剂量依赖地诱导LRP的mRNA、蛋白表达水平。干扰AhR表达后,该三种苯胺类毒物不能诱导LRP的mRNA与蛋白表达。MTT实验结果表明,对苯二胺、间苯二胺、邻苯二胺能够下调抗肿瘤药物吉非替尼、吉西他滨对A549细胞的杀伤作用:吉非替尼作用于A549细胞的IC50值从1.20±0.25μmol/L上调为5.67±0.44μmol/L、6.07±0.30μmol/L与7.51±0.28μmol/L,其耐药指数(resistance folds)分别为4.73、5.06与6.26;吉西他滨作用于A549细胞的IC50值从0.44±0.10μmol/L上调至1.55±0.25 μmol/L、1.88±0.19 μmol/L与2.33±0.40 μmol/L,其耐药指数分别为3.52、4.27与5.30。结论:三种代表性苯胺类毒物能够在肺癌细胞中通过AhR诱导LRP表达,并且能够引起A549对抗肿瘤药物耐受。  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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