CEA是指（）
A.甲胎蛋白
B.肿瘤相关抗原
C.癌基因
D.癌胚抗原
E.抑癌基因
参考答案：D
Audiences and critics were _____ by its originality, vitality, and excitement of the Beijing Olympic opening ceremony. [ ]
A. happened
B. reflected
C. occurred
D. struck
开放性骨折防止感染的首要措施是（）
A.注射大量抗生素
B.及时彻底清创
C.迅速复位和内固定
D.手法复位和外固定
E.彻底清除碎骨片和异物
