典型心房扑动的发病机制是
A.心房自律性增强
B.交界区自律性增强
C.触发活动
D.传导异常
E.折返机制
参考答案:E
Of the 9,500 drivers since the beginning of the year, 23% were found lacking road
knowledge.
A.test
B.testing
C.tested
D.were tested
具有刺吸式口器的昆虫是()
A.蝗虫
B.蚊子
C.蝼蛄
D.臭蝽