QT间期指心电波形中QRS波起点到T波终点这一段所对应的时间间隔，代表心室去极化过程。

As the interval between QRS waves and T wave in ECG, QT interval represents the depolarization of ventricle.

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Now, that rapid rise is called depolarization and the membrane is said to be in a depolarized state because it's less polarized or less negatively charged repolarized as negatively charged.

这个迅速上升过程称为去极化,我们称膜处于去极化状态,因为膜的极化程度降低了,或者说是带的负电减少了,而复极化就代表重新带上负电荷

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