第5题: [单项选择]患有菌群交替症的病人,粪便的致病菌常为 A. 固定一种细菌 B. 固定两种细菌 C. 正常菌群的比例失调 D. 固定多种细菌 E. 以上均不对 参考答案:C 答案解析:长期使用广谱抗生素、免疫抑制剂及慢性消耗性疾病患者可发生肠道菌群失调,引起革兰阴性杆菌数量严重减少甚至消失,而葡萄球菌或真菌等明显增多,粪便中球菌/杆菌比值变大。
第19题: [单项选择]Questions 11 to 18 are based on the conversation you have just heard. A. Robert survived the plane crash. B. All the passengers were killed in the plane crash. C. Robert was killed in the air crash. D. Robert is a wonder-working person. 参考答案:A 答案解析:[听力原文] W: It’s a miracle that Robert came out of the air crash alive. M: That’s indeed a mirac