下列哪种情况可出现二氧化碳结合力升高
A．创伤性休克
B．急性肾功能衰竭
C．呼吸道梗阻
D．癔病
E．高热
参考答案：C
The man we followed suddenly stopped and looked as if ______ whether he was going in the right direction.
A．seeing
B．having seen
C．to see
D．to have seen
缺乏可导致毛细血管脆性增加，伤口愈合延缓的是（）
A.维生素A
B.维生素B
C.维生素C
D.维生素D
E.维生素E
