题型:选择题 The opening ceremony of the 29th Olympic Games started ______ August 8thin the National Stadium in Beijing. [ ]A. at B. on C. in D. for 查看答案
题型:单项选择题 女性,50岁,经食管钡餐X线检查诊为食管中段癌。请问食管癌的特征除外下列何种情况()A.最常发生于食管中段B.肿瘤可呈多点起源发生C.细胞类型以鳞癌多见D.食管中段癌预后最佳E.男性患者多于女性患者 查看答案