检测HP感染属侵入法的是()
A.HP培养
B.血清HP检查
C."C或"C尿素呼气试验
D.粪便幽门螺杆菌抗原检测
E.检测血PCA和IFA
参考答案:A
______ you think he ______ back by dinner time?
a. Do/have come b. Did/will have come c. Does/will come d. Do/will have come
酸雨的临界值是______。
A.pH=6.0 B.pH=10 C.pH=5.6 D.pH=4.0