PPL型起搏器质量检测系统的研制

介绍了ＰＰＬ型心脏起搏器质量检测系统．该系统可自动巡捡０～９９路起搏器电路的性能参数，并可随时报警，打印异常情况．该设备可用于生产过程中产品质量的控制．     

兔窦房结细胞的分离方法及其起搏电流特征性探讨

 探讨了家兔窦房结(Sino-Atrial Node,SAN)细胞的分离方法及其形态和起搏电流(Funny Current,I_f)的特征.通过打结定位法确定了带有"中心结区"的家兔SAN组织条,双酶法分离SAN细胞,利用全细胞穿孔膜片钳技术记录SAN细胞的I_f.结果显示,SAN组织为上宽下窄的枣核型,区域体积约为6.25mm×2.23mm×0.26mm,或6mm×2mm×0.1mm—6mm×2mm×3.3mm.SAN细胞成狭长梭形,无清晰横纹,细胞长(65.3±7.8)μm,宽为(7.2±3.1)μm.在正常Tyrode液中,可恢复规则自律性搏动,频率为(187.3±5.6)次/min,典型SAN细胞数量占整个分离细胞的2%—5%.根据电压钳制方案,I_f电流被引出,呈内向性斜坡状,随着钳制电压降低,起搏电流逐渐增大,并随钳制时间延长,倾斜度也增大.I_f带有明显尾电流,也随着超级化激活电位降低,逐渐增大.根据二者电流大小拟合的电流-电压曲线,呈典型横向Y形.本法获得SAN细胞形态典型,状态和活性良好,能够记录具有特征性的I_f,可供心血管领域有关针对SAN细胞I_f研究的技术借鉴.     

五指山小型猪心脏起搏器的放置

将体重为 2 4— 2 6kg的成年五指山小型猪 ,用于颈外静脉放置心脏起搏器的实验研究 ,结果表明此方法操作简单 ,起搏效果好 ,为建立理想的心衰模型提供了可靠的技术方法和措施 ,为小型猪的心衰模型系列开发利用奠定了良好基础。     

HCN channels: Structure, cellular regulation and physiological function

Hyperpolarization-activated and cyclic nucleotide-gated (HCN) channels belong to the superfamily of voltage-gated pore loop channels. HCN channels are unique among vertebrate voltage-gated ion channels, in that they have a reverse voltage-dependence that leads to activation upon hyperpolarization. In addition, voltage-dependent opening of these channels is directly regulated by the binding of cAMP. HCN channels are encoded by four genes (HCN1–4) and are widely expressed throughout the heart and the central nervous system. The current flowing through HCN channels, designated I_h or I_f, plays a key role in the control of cardiac and neuronal rhythmicity (“pacemaker current”). In addition, I_h contributes to several other neuronal processes, including determination of resting membrane potential, dendritic integration and synaptic transmission. In this review we give an overview on structure, function and regulation of HCN channels. Particular emphasis will be laid on the complex roles of these channels for neuronal function and cardiac rhythmicity. Received 22 August 2008; received after revision 22 September 2008; accepted 24 September 2008     

安装临时起搏器护理2例

目的为了更好的提高对安装临时起搏器术后的护理效果。方法对2例安装临时起搏器整个过程进行观察和护理。结果通过护理无1例发生并发症,均获手术成功。结论加强术前、术中、术后护理,为确保患者顺利康复起到了重要作用。     

右室流出道螺旋电极永久性起搏器的临床应用

目的探讨右室流出道起搏螺旋电极永久性起搏器的临床应用效果。方法对6例患者进行了右室流出道螺旋电极永久性起搏器安装手术。结果所有病例都顺利完成手术,未出现严重并发症。结论右室流出道起搏比右室心尖部起搏明显改善血流动力学,改善心力衰竭患者的心功能;急性和慢性起搏参数均良好,起搏安全可靠。     

Cardiac cellular electrophysiology: past and present

Summary The time-course of the cardiac action potential can be accounted for in terms of ionic currents crossing the cell membranes. Depolarizing current is carried by Na⁺ or Ca²⁺ entering the cells, repolarizing current by K⁺ leaving the cells. Membrane permeability for the passive movement of these ions is thought to be voltage-dependent as well as time-dependent. Net transfer of charge may also result from active transport, 2 Na⁺ out against 1 K⁺ in; or coupled exchange, 3 or 4 Na⁺ in against 1 Ca²⁺ out. This review follows the path by which present-day knowledge has been reached. It also gives a few examples to illustrate that electrophysiology has provided concepts useful to clinical cardiology.