消化道肿瘤最常用的疗效考察指标是()
A.AFP
B.CEA
C.CA125
D.CA15-3
E.PSA
参考答案:B
A teenager is someone who can hear a song by Lady Gaga _______ three blocks away but not his mother ________ from the next door.
A.playing; calling
B.playing; called
C.played; called
D.played; calling
碘量法测定废气中硫化氢时,易受其他氧化性和还原性气体的干扰。