手工钨极氩弧焊时焊接速度增加,则保护效果()。
A.增加
B.不变
C.减弱
参考答案:C
麻醉前用药的选择,下列哪种说法不正确()。
A.全麻病人以镇静药和抗胆碱药为主
B.腰麻病人以镇静药为主
C.冠心病及高血压病人的镇静药剂量可适当减少
D.心脏瓣膜病、心功能差及病情严重者,镇静及镇痛药的剂量应酌减
E.年轻体壮或甲亢病人,镇静及镇痛药的剂量应酌增
Of the making of good books there is no end; neither ________ any end to their influence on man's lives.[ ]
A. there is
B. there are
C. is there
D. are there