正在使用的热电偶温度变送器,如果某一部分出现问题,那么可以使用热电阻温度变送器的()部分进行替代。
A、输入
B、放大
C、反馈
D、比较
参考答案:B
The successful spread of a virus depends on how long it can (74) unnoticed, before its presence is made known by the activation of side-effects. For example, many viruses (75) their code to avoid recognition.
A.move
B.replicate
C.backup
D.die out
下列哪项不是食管超声心动图的适应证()
A.食管病变、静脉曲张
B.瓣膜成形术
C.需体外循环的先心病手术
D.肥厚性心肌病左室流出道疏通术
E.先心病诊断