皮牵引的重量一般不超过()。
A.2kg
B.3kg
C.4kg
D.5kg
E.6kg
参考答案:D
医师和药学专业技术人员在药物临床应用时须遵循的原则包括()
A.安全
B.有效
C.经济
D.适当
E.尊重患者的知情权
—I hear Mr. Zhang has gone to Beijing for a meeting.
—Really? Do you know when he ______?[ ]
A. leaves
B. was leaving
C. has left
D. left