多巴酚丁胺与β阻滞剂合用使,效应占优势,引起周围血管阻力增大的机理是
A.心搏出量增加
B.血压升高
C.β-作用被阻断
D.加剧血管收缩
E.血压剧降
参考答案:C
It was with great joy _____ he received the news that his lost daughter had been found. [ ]
A. because
B. which
C. since
D. that
玉溪电网新设备投运调度管理遵循“()、()”的原则。
A.统一调度
B.分级管理
C.统一管理
D.分级调度