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Maxime Caru François Lalonde Hugo Gravel Chantal Daigle François Tournoux Vincent Jacquemet 《European Journal of Sport Science》2016,16(8):1005-1013
The protective action of remote ischaemic preconditioning (RIPC) has been demonstrated in the context of surgical interventions in cardiology. Application of RIPC to sports performance has been proposed, but its effect on the electrocardiogram (ECG) during exercise remains unknown. This exploratory study aims to measure the changes in ventricular repolarization observed during exercise following RIPC in healthy subjects. In an experimental randomized crossover study, 17 subjects underwent two bouts of constant load exercise tests at 75% and 115% of gas exchange threshold (GET). Prior to exercise, they were allocated to either control or RIPC intervention with four cycles of 5?min of ischaemia followed by 5?min of reperfusion. ECG was continuously recorded during the protocol. QT and RR intervals were measured every 30?s (on an average tracing of the preceding 10?s). Although the time course of RR intervals did not differ between the two interventions (p?=?.56 at 75% GET and p?=?.74 at 115% GET), a significant shortening of QT intervals (measured from Q onset to T end) was observed during exercise (mean?±?standard deviation of RIPC vs. control: ?32?±?19?ms at 75% GET (p?p?p?p?相似文献
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目前,国内外运动生理学领域中有关诱发脑电的研究尚属不多,而有关CNV的报导更是少见。本文通过对射击、短距离、球类等各专项组运动员CNV的波幅、面积、时程的比较,分析各组间的差异,阐明了以CNV作为有关专项运动员中枢神经系统的选材和脑功能评定的电生理学指标的可行性。 相似文献
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目的 :探讨CsCl对心脏慢反应自律细胞的电生理效应。方法 :应用细胞内微电极记录技术 ,观察了 16例家兔窦房结和主动脉前庭 (左心室流出道 )自律细胞动作电位的特征。以分析CsCl对窦房结和流出道自律细胞作用的异同。结果 :给予 2mmol/LCsCl灌流后 ,两自律细胞自发慢反应电位的VDD及RPF均明显减慢 (P <0 .0 5 ) ,10min左右达到最大效应 ,而MDP、APA、Vmax、APD、APD50 、APD90 与正常对照比均无明显差别 (P >0 .0 5 )。结论 :CsCl对窦房结起搏细胞和主动脉前庭自律细胞的起搏离子流有明显抑制作用。 相似文献
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目的 探讨腺苷对房室结折返性心动过速患者（AVNRT）房室结双径路传导现象（DAVNP）的诊断价值。方法 对53例阵发性室上性心动过速（PSVT）患者在窦性心律下经外周静脉推注递增剂量的腺苷后观察体表心电图上房室传导时间的变化。其中18例AVNRT患者在慢径消融术后行再次腺苷检查。结果 有31例慢快径咱折返性心动过速患者中有26例出现PR间期突然跳跃达60ms以上，20例房到折返性心动过速（AVRT）及2例房性心动过速（AT）中仅2例出现此现象（P＜0.01），18例AVNRT患者在慢径消融成功后电生理检查示8例慢径消失，6例存在DAVNP，但在静推腺苷时沿慢径下传的激动显著减少（P＜0.01）。结论 房室结双径路前传时快径路对腺苷的敏感性要高于慢径路，窦性心律下静脉推注腺苷是床边诊断房室结折返性心动过速患者双径路传导现象的有效方法，对心房程序扫描刺激未能发现房室传导时间跳跃时腺苷推注有助于房室结双径路的诊断。 相似文献
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视网膜电图可用于评判视觉系统的发育、功能及病变,已成为眼科必备检查项目之一。目前已开发商用系统仅用于人类眼科检查和大的动物研究,无法用于斑马鱼视网膜功能测量。利用玻璃电极、四维度微操、LED光刺激模块及电生理放大器,搭建了适合于幼小斑马鱼视网膜电图测量的系统,系统具有高信噪比、适应性强、方便操作、实验成功率高等优点,将在斑马鱼视觉系统发育、遗传学研究等方面发挥积极的作用。 相似文献
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Simulation of biatrial conduction via different pathways during sinus rhythm with a detailed human atrial model 总被引：1，自引：1，他引：0
Dong-dong Deng Ying-lan Gong Guo-fa Shou Pei-feng Jiao Heng-gui Zhang Xue-song Ye Ling Xia 《Journal of Zhejiang University. Science. B》2012,13(9):676-694
In order to better understand biatrial conduction, investigate various conduction pathways, and compare the differences between isotropic and anisotropic conductions in human atria, we present a simulation study of biatrial conduction with known/assumed conduction pathways using a recently developed human atrial model. In addition to known pathways: (1) Bachmann’s bundle (BB), (2) limbus of fossa ovalis (LFO), and (3) coronary sinus (CS), we also hypothesize that there exist two fast conduction bundles that connect the crista terminalis (CT), LFO, and CS. Our simulation demonstrates that use of these fast conduction bundles results in a conduction pattern consistent with experimental data. The comparison of isotropic and anisotropoic conductions in the BB case showed that the atrial working muscles had small effect on conduction time and conduction speed, although the conductivities assigned in anisotropic conduction were two to four times higher than the isotropic conduction. In conclusion, we suggest that the hypothesized intercaval bundles play a significant role in the biatrial conduction and that myofiber orientation has larger effects on the conduction system than the atrial working muscles. This study presents readers with new insights into human atrial conduction. 相似文献
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目的 :为进一步阐明Ca2 + 通道在心脏起搏中所起的作用 ,及左心室流出道 (主动脉前庭 )自律细胞的特性。方法 :利用常规的玻璃微电极细胞内记录技术 ,观察了 2 6例家兔窦房结和左心室流出道自律细胞动作电位的特征。以分析钙通道阻断剂 -维拉帕米 (VER)和氯化镍 (NiCl2 )对窦房结和流出道自律细胞的影响。结果 :(1)用 1μmol/LVER灌流后窦房结及主动脉前庭自律细胞的APA、Vmax、MDP绝对值、VDD、RPF均明显下降 ,APD90 延长 (P <0 .0 5 )。 (2 )用 180 μmol/LNiCl2 灌流后两自律细胞自发慢反应电位的VDD、APA、Vmax、RPF均明显下降 (P <0 .0 1) ,而且窦房结细胞APD90 也显著延长 ;二者的MDP、APD50 均无明显改变 (P >0 .0 5 )。结论 :钙通道阻断剂对窦房结起搏细胞和主动脉前庭自律细胞动作电位 0相和 4相去极离子流有明显抑制作用。 相似文献
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目的:研究普罗帕酮对心室肌细胞的影响作用.方法:应用常规的玻璃微电极细胞内记录技术,观察普罗帕酮对豚鼠心室肌细胞的动作电位0相幅值(APA),最大除极速率(Vmax),动作电位时程(APD),50%复极化时间(D50),90%复极化时间(D90).结果:(1)用5μmol/L的普罗帕酮灌流后与正常对照组相比动作电位0幅值(APA)下降(P＜0.05),动作电位时程(APD)及50%复极化时间(D50)升高(P＜0.05),(3)用10μmol/L的普罗帕酮灌流后与正常对照组相比动作电位0幅值(APA)下降(P＜0.05),动作电位时程(APD)明显升高(P＜0.01),50%复极化时间(D50)及90%复极化时间(D90)升高(P＜0.05).结论:普罗帕酮能抑制心室肌细胞的动作电位0幅值,延长动作电位时程、最大除极速率及50%、90%复极化时间. 相似文献
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英国生理学家阿奇博尔德·希尔长期从事神经生理学研究并做出了重要贡献。他首次发现神经受刺激后的产热现象并对此进行了深入探讨。他提出高度概括的电兴奋与适应的成功理论,对电生理学的发展产生了积极影响。本文对希尔在神经生理学领：战的工作和贡献进行历史性回顾,并揭示其现实的深刻启示,以期为今后的科学研究提供借鉴。 相似文献
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