对于肥厚梗阻型心肌病患者,下列措施会使心脏杂音减弱的是()
A.深吸气
B.下蹲后站立
C.运动
D.Valsalva动作
E.含服硝酸甘油
参考答案:A
I stayed up late doing my homework yesterday, so I had trouble _____ up early this morning.[ ]
A. get
B. getting
C. got
D. to get
氧气、乙炔瓶应距离明火多少米以上?使用时,两瓶间距多少米以上?