常見例句Activation of the heart normally begins in the sinoatrial node.在正常情況下，心髒的活動始於竇房結。This process continues over and over as the atria refill with blood and other electrical signals come from the SA node.隨著心房的再次充血和竇房結電信號的再次産生，這個過程會一直重複下去。 返回 SA node