甲状腺吸碘131率增高,同时高峰前移,见于()
A.甲状腺功能亢进症
B.单纯性甲状腺肿
C.女性青春期
D.妊娠8周以上
E.地方性缺碘性甲状腺肿
参考答案:A
经典的蛋白质抗原纯化分离方法为
A.盐析沉淀法B.有机溶剂沉淀法C.凝胶过滤D.离子交换层析E.亲和层析
Harry ______ Helen with her lessons at this time yesterday. [ ]
A. is helping
B. helps
C. was helping
D. helped