缓解肺气肿患者呼吸困难的首选措施是
A．胸腔引流
B．通畅呼吸道，持续低流量吸氧
C．镇静剂
D．强心剂
E．呼吸兴奋剂
参考答案：B
— The little boat is ______ safe . Don't you think so, Mike ?
— No worries! I've on this boat dozens of times.[ ]
A. something but
B. nothing but
C. anything but
D. everything but
抓好资金管理，确保项目资金专款专用是进度控制的( )。
A．组织措施 B．技术措施C．经济措施 D．合同措施
