梗阻性黄疸时,BUS显示胆总管和肝内胆管均不扩张,为明确诊断应选择哪项检查()
A.放射性核素胰腺扫描
B.PTC
C.低张十二指肠造影
D.ERCP
E.CT
参考答案:D
Tom hurried to school only to find that there was none because it was Sunday and he _____to school.
A.couldn’t have gone
B.needn’t have gone
C.mustn’t go
D.needn’t go
计算机病毒的特征()
A.隐蔽性
B.潜伏性,传染性
C.破坏性
D.可触发性
E.以上都正确