第15题: [单项选择]A. He has had thirteen decayed teeth. B. He doesn’t have a single decayed tooth. C. He has fewer decayed teeth than other people of his age. D. He never had a single tooth pulled out before he was fifty. 参考答案:B 答案解析:[听力原文] What does the passage tell us about the condition of Dr. Faustick’s teeth
第21题: [单项选择]目前最有效的杀包囊药是() A. 甲硝唑 B. 二氯尼特 C. 喹碘方 D. 氯喹 E. 乙酰砷胺 参考答案:B 答案解析:二氯尼特口服后,主要靠其未吸收部分杀灭阿米巴原虫的囊前期,是目前最有效的杀包囊药。喹碘方口服吸收较少,可用于肠内阿米巴病,如排包囊者;或与甲硝唑合用治疗急性阿米巴痢疾。甲硝唑是目前治疗贾第鞭毛虫病最有