题型:单项选择题 女孩,3岁。发热4d,初热不高,流清涕,次日咳嗽,胃纳差,后持续高热,咳加剧声音嘶哑,眼结膜充血,耳后、颈部出现斑丘疹,部分融合,疹间皮肤正常。从外地到上海,未接受任何预防接种,2周前用过青霉素。最可能的诊断是A.猩红热B.药物疹C.麻疹D.荨麻疹E.以上均不是 查看答案
题型:选择题 I didn't see your sister at the meeting. If she _____, she would have met my brother. [ ]A. has comeB. did comeC. came D. had come 查看答案
题型:单项选择题 比较真核生物与原核生物的DNA复制,它们的相同之处是A.引物长度较短B.合成方向自5'→3'C.冈崎片段长度短D.有多个复制起始点E.DNA复制的速度较慢(100dNTP/s) 查看答案