气管套囊的压力不能超过()
A.18mmHg
B.25mmHg
C.30mmHg
D.32mmHg
E.40mmHg
参考答案:D
There a pen,two pencils and three rulers in the box.[ ]
A.is
B.are
C.has
D.have
下列哪项不符合胃溃疡癌变的特点
A.上腹痛的规律性消失B.食欲减退C.进行性贫血、消瘦D.大便潜血持续阳性E.反酸烧心加重