与哮喘气流受限机制有关的是()
A.管腔内粘液栓阻塞
B.气道壁重建
C.支气管平滑肌收缩
D.肺泡过度充气
E.支气管壁水肿
参考答案:A, B, C, D, E
—It’s very modern,but they have some antique________ in it.
A.furniture B.furnitures
C.piece of furnitures D piece of furniture
如果电动机外壳未接地,当电动机发生一相碰壳时,它的外壳就带有()
A.线电压
B.线电流
C.相电压
D.相电流