消化性溃疡最常见的并发症为（）
A.穿孔
B.出血
C.幽门梗阻
D.癌变
E.瘘管形成
参考答案：B
—Did you enjoy your journey to the town?
— _______. We had driven more than 3 hours before we found the right way.
A．Absolutely
B．No way
C．Not at all
D．Quiet a lot
白细胞分化成熟不同阶段的所表达的细胞表面标志是（）
A.CD
B.CAM
C.CR1
D.CKR
E.FcR
