电流型逆变器中间直流环节贮能元件是()。
A.电容
B.电感
C.蓄电池
D.电动机
参考答案:B
The research project has only been under way for three months, so it's too early to________its success.[ ]
A. conclude
B. evaluate
C. indicate
D. reveal
36岁,男性,呕吐2h入院。检查中又呕血约500ml,血压9/7kPa(70/55mmHg),皮肤湿冷,神志恍惚,腹膨隆,脾于肋弓下2cm,腹水征阳性。最应如何治疗()
A.立即手术止血
B.补充血容量后紧急手术
C.补充血容量及静脉用止血药
D.补充血容量及三腔二囊管压迫止血