阵发性高血压,发作时伴有头痛、面色苍白、出汗、心动过速等,α受体阻滞剂有效()
A.肾动脉狭窄
B.原发性醛固酮增多症
C.尿毒症
D.皮质醇增多症
E.嗜铬细胞瘤
参考答案:E
对人体来讲,安全电压应不高于______伏.
the end of last term, every student in the school, I think, has taken at least five maths tests.
A.By
B.Since
C.From
D.In