雷诺现象或雷诺病发病的病理生理机制为()
A.手指足趾小动脉间隙性痉挛
B.末梢细小动脉对寒冷反应性痉挛
C.淋巴水肿
D.静脉痉挛导致淤血
E.小动脉扩张
参考答案:A
--- Do you mind telling us something about this area?
--- Not at all. ________ of the land in this area _________ covered with trees and grass.
A.Two fifth, is
B.Two fifth, are
C.Two fifths, is
D.Two fifths, are
消除及避免引起虚劳的病因是预防虚劳的根本措施。