Characteristics of Early Afterdepolarization in Mouse Atrial Fibers

Early afterdepolarization (EAD) in mouse atrial fibers was investigated under the treatment with aconitine, 3. 0 mmol/L K+ ,quinidine, ryanodine or Bay k 8644. All of these EADs possessed the following common characteristics j all the parameters of EAD showed cycle length-dependence; take-off potential of the first triggered burst played an important role in the generation of the other parameters ; hyper-polarization of the triggered brust enhanced the end of EAD; and the second plateau response might be used as an indicator of the capability of EAD generation of myocardiac cell. All those EADs were inhibited or abolished by nifedipine, tetrodotoxin or lidocaine. Potassium channel activators, lemakalim, thalium ion, acetyl-choline or high potassium could also inhibit or abolish the EADs. It is suggested that the EADs induced by different agents may base on a common mechanism ; all currents contributing to the plateau phase of the action potential play an important role in the generation of EAD.     

全息全感幼儿英语教学法探索

本文结合目前我国儿童英语教育现状及幼儿英语教学法的发展,介绍了全息全感幼儿英语教学法,并分析其与另一流行的全身反应法的区别和联系,总结了在进行幼儿英语教学时,应注意的一些问题。     

汉语正迁移在英语基本功写作训练中的应用

英语基本功写作训练是英语技能教学的重要教学内容。本文分析了影响学生英语基本功写作能力提高的原因,运用心理学的迁移原理,论述了汉语学习的正迁移有利于提高学生的英语写作技能。     

小鼠心房肌早发后去极化的特性

在小鼠心房肌上观察了由乌头碱、3.0mmol/L K~+、奎尼丁、ryanodine及Bay k8644引起的早发后去极化(EAD)。这些EAD具有以下共同特性:EAD的诸参数均呈周长依赖性;其中第一个触发发放的起步电位对其他参数起决定性作用;触发发放的后超极化促进EAD结束;第二平台反应是心肌细胞产生EAD能力的指标。上述所有EAD均可由硝苯吡啶、河豚毒素或利多卡因抑制或消除。钾通道激动剂:lemakalim,Ti~+,乙酰胆碱或高钾也可抑制或消除EAD。结果提示,由不同因素引起的EAD可能基于下列共同机制:参与动作电位平台期的各种电流均可在EAD形成中发生作用。