预防偏头痛下列药物哪种无效( )。
A.心得安 B.阿密替林C.羟甲丙基甲基麦角酰胺 D.盐酸塞庚啶E.氧可酮
参考答案:E
解析: 常见症状的自我药疗
夏至日的日期为________前后,太阳直射在________,北半球昼夜长短状况为________。
Harvard,_____________ in 1636, is one of the most famous universities in the USA.[ ]
A. which is set up
B. which is built
C. which was
D. which was