胸肺顺应性的简易计算方法是潮气量除以()
A.平台压-呼气末压
B.峰压
C.呼气末压
D.平台压
E.气道阻力
参考答案:A
根据句意,选用适当的词填空。
1. —Is this your pencil?
—No,it isn't. ______ (That,That's) my pencil.
2. —What's this?
—______(It's, Its) a red pen.
3. I can see______ (a, an) English girl.
4. —______(What's, What)color is the clock?
—It's white.
5. —Excuse ______ (I, me),Sally. Is this your book?
—No, it isn't.
背压式汽轮机启动时,要先开启汽封抽气器的原因是()。
A、防止背压蒸汽串入其它系统
B、增加背压蒸汽温度
C、暖管
D、防止不凝气积聚