消化性溃疡X线检查最具诊断意义的是：()
A．辐射状黏膜
B．痉挛性切迹
C．球部激惹
D．局部压痛
E．龛影
参考答案：E
Although he failed this time, he didn’t give up and ＿＿＿＿＿＿studying hard.
A．stopped
B．continued
C．succeeded
D．finished
绝缘油介质损耗测试仪，测量电极与保护电极间的绝缘电阻，应为测量设备绝缘电阻的（）倍以上。
A.20
B.50
C.100
D.200
