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1.
血竭对大鼠背根神经节细胞钠通道电流的影响   总被引:8,自引:0,他引:8  
研究血竭对大鼠背根神经节细胞电压门控性钠通道电流的影响。方法:采用全细胞膜片钳记录法,在新鲜分离的大鼠背根神经节细胞上观察血竭对钠通道电流幅值的影响。结果:血竭剂量依赖地抑制单个DRG细胞电压门控性钠通道电流,高剂量的血竭抑制作用不可逆。结论:血竭对背根神经节细胞钠通道电流的这种抑制作用,可能是其产生躯体镇痛作用的药理机制之一。  相似文献   

2.
目的:观察血竭总黄酮对小鼠三叉神经节(TG)细胞河豚毒素敏感型(TTX-S)钠通道电流的影响,确定血竭对TG细胞电压门控性钠通道电流产生抑制效应的有效部位.方法:酶解法急性分离昆明种小鼠(1月龄)三叉神经节细胞,应用全细胞膜片钳技术记录TG 细胞TTX-S钠通道电流,观察血竭总黄酮对其影响.结果:在钳制电位为-90 mV时,3种浓度(0.001 %,0.01 %,0.1 %)的血竭总黄酮对锋钠电流的抑制率分别为17.02±5.42 %,33.23±5.12 %,49.30±5.14 %(P值均小于0.05),抑制效应呈典型的浓度依赖性,血竭总黄酮对TG细胞TTX-S锋钠电流的半数抑制浓度(IC50)为0.101 3 %.结论:血竭总黄酮是血竭抑制TG细胞TTX-S钠通道电流的有效部位,该研究为血竭有效成分的提取缩小了研究范围.  相似文献   

3.
用膜片钳技术分析了棉铃虫三氟氯氰菊酯抗性品系(R)及其同源对照品系(S)不同龄期幼虫神经细胞电压门控Na^ 通道的电生理特性.结果表明,S幼虫神经细胞Na^ 通道的激活电压介于-50~-30mV,约70%细胞的Na^ 通道在-40mV左右激活.Na^ 通道电流(1Na)的峰值电压介于-30~0mV,约72%细胞的1Na在-20mV左右达峰值.R幼虫Na^ 通道的激活电压介于-50~-20mV,约60%细胞的Na^ 通道在-40mV左右激活,约30%的在-30~-20mV激活.2龄幼虫(R2)约76%细胞的1Na在-20mV左右达峰值.R3和R4均有60%以上细胞的INa在-10~OmV达峰值,即R3和R4多数细胞1Na的峰值电压向正电位方向移动.上述结果表明R幼虫神经细胞Na^ 通道功能发生了变异,同时也提示R幼虫在不同发育阶段其Na^ 通道的表达不同.  相似文献   

4.
采用酸提、碱化、萃取等步骤提取青椒中的生物碱类成分,以苯-醋酸乙酯-无水乙醇-氨水(体积比为24:3:1:O.5)为展开剂;采用醇提、酸溶、碱化、萃取等步骤提取血竭中的血竭素,以氯仿-甲醇(19:1)为展开剂.鉴别项下层析图谱清晰,阴性对照无干扰,专属性强,该法简便、准确、重现性好,可作为控制中药消糜栓中青椒、血竭质量的鉴别项。  相似文献   

5.
利用全细胞膜片钳技术检测了新型杀虫剂烯啶虫胺(Nitenpyram)对急性离体培养的棉铃虫Helicoverpaarmigera(Hübner)中枢神经细胞电压门控钠和钙通道的影响.结果表明:烯啶虫胺对棉铃虫神经元TTX敏感型钠通道和L-型钙通道的峰值电流有显著抑制作用;药物作用后,钠及L-型钙通道的激活曲线均左移,钠通道半数激活电压向超极化方向移动约3 mV,钙通道半数激活电压向超极化方向移动约7 mV,均具有统计学差异;烯啶虫胺对钠和L-型钙通道的失活也有影响,使半数失活电压均向超极化方向移动,钠通道的V0.5偏移约2 mV,钙通道的V0.5偏移约5 mV,均具有显著性差异. 另外,烯啶虫胺可显著增大钠通道和L-型钙通道的窗口电流. 最终确认烯啶虫胺对棉铃虫幼虫中枢神经元TTX敏感钠通道和L-型钙通道的峰值电流及通道的激活和失活都有影响,使钠、钙通道窗口电流增大,棉铃虫中枢神经细胞的钠、钙通道为烯啶虫胺的潜在作用靶标.  相似文献   

6.
用全细胞膜片钳技术分析了棉铃虫Helicoverpa armigera(Hübner)幼虫中枢神经细胞电压门控Ca~(2+)通道的电生理学特性,并检测了三氟氯氰菊酯(cyhalothrin,Cyh)对Ca~(2+)通道功能特性的影响.结果表明,Ca~(2+)通道电流(I_(Ca))激活阈值-40 mV,峰值电压介于-10 mV-10 mV.约82%细胞的I_(Ca)在-20 mV激活,93%细胞的I_(Ca)在0 mV左右达峰值.棉铃虫表达高电压激活、对Cd~(2+)敏感的Ca~(2+)通道和高电压激活、对Cd~(2+)不敏感的Ca~(2+)通道.Cyh作用后,I_(Ca)在幅值减小的同时,I-V曲线和激活曲线均向超极化方向移动10-20 mV,表明Cyh不仅对I_(Ca)有抑制作用,对Ca~(2+)通道的激活也有影响,棉铃虫幼虫腹神经索中枢神经细胞高电压门控Ca~(2+)通道也是Cyh的作用靶标之一.  相似文献   

7.
建立高效液相色谱法测定骨筋丸胶囊中血竭素含量的方法。方法:选用Hypersil BDS色谱柱(150mm×4.6mm,5μm),乙腈-0.05molo-磷酸二氢钠溶液(40:60),流速:1.0mL·min^-1;检测波长:440nto。结果:血竭素在0.08-072μg内线性关系良好(r=0.9999),平均回收率为100.94%,RSD=1.29%(n=6)。结论:方法简便、快速、准确,能有效地控制骨筋丸胶囊质量。  相似文献   

8.
应用全细胞膜片钳技术记录急性分离的小鼠三叉神经节细胞电压门控性钠通道电流,观察白细胞介素-1β对河豚毒素敏感性钠电流的影响,拟从离子通道水平探讨白细胞介素-1β调节颜面部痛的分子机制.结果发现白细胞介素-1β双相调节三叉神经节细胞河豚毒素敏感性钠通道,低浓度白细胞介素-1β(1ng/mL和10ng/mL)抑制三叉神经节细胞河豚毒素敏感性钠电流锋值,其中1ng/mL白细胞介素-1β使河豚毒素敏感性钠通道半失活电压向超极化方向偏移,复活时间常数延长.高浓度白细胞介素-1β(100ng/mL)在给药即刻增强三叉神经节细胞河豚毒素敏感性钠电流锋值,使河豚毒素敏感性钠通道半激活电压向超极化方向偏移,而不影响其失活及复活特性.高、低浓度白细胞介素-1β对三叉神经节细胞河豚毒素敏感性钠电流锋值的效应具有可逆性特点.结果表明白细胞介素-1β双相调节三叉神经节细胞河豚毒素敏感性钠通道,可部分解释白细胞介素-1β双相调节痛觉的产生及对神经元的损害和保护双相效应.  相似文献   

9.
探讨电压门控钾离子通道在乳腺上皮细胞增殖过程中的作用.通过MTT法检测了钾通道阻断剂TEA、电压门控钾通道阻断剂4-AP对人乳腺上皮细胞MCF10A增殖的影响并与乳腺癌细胞MCF7作了比较,免疫印迹方法观察了电压门控钾通道Kv1.2、Kv1.5的表达.研究发现,两种钾离子通道阻断剂对人乳腺细胞和乳腺癌细胞增殖的影响均呈剂量依赖性关系.经5mmol/LTEA处理72h后,MCF10A细胞的生长抑制率为21.67%,而MCF7细胞的生长抑制率为41.36%;5mmol/L 4-AP处理72h后,MCF10A的生长抑制率为29.24%,而MCF7细胞的生长抑制率为40.24%.Kv1.2在MCF10A和MCF7中表达没有变化.而Kv1.5在MCF10A细胞中的表达明显高于MCF7细胞.提示电压门控钾离子通道在乳腺细胞的增殖中起重要作用,其中Kv1.5可能和乳腺细胞的转化密切相关.  相似文献   

10.
Navβ1亚基是电压门控钠离子通道的辅助亚基之一,调控通道的门控特性,以及通道的激活和失活。而Navβ1亚基对KCNQ通道的调控作用尚不清晰。文章利用全细胞膜片钳技术检测了Navβ1亚基对异源表达的KCNQ通道及其亚型的电流调控特征。实验结果发现,Navβ1亚基可以差异性调控KCNQ通道的电流特性,抑制KCNQ1和KCNQ2通道的活性,而激活KCNQ3和KCNQ4通道,延缓KCNQ1通道的激活,易化KCNQ3和KCNQ4通道的激活。研究首次发现了Navβ1亚基对KCNQ通道的差异性调控作用,为解析KCNQ通道的功能以及相关疾病的诊疗提供新思路。  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.
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   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  相似文献   

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