关于腰椎前后位摄片的叙述,下列哪项是错误()
A.常规位置
B.必须使用滤线器
C.常与侧位片一同摄取
D.X线管阴极端必须对上部腰椎
E.取深呼气后屏气曝光
参考答案:D
The little boy was at the murder’s face with a gun in his hand.
A.frightening; frightened
B.frightened; frightening
C.frightened; frightened
D.frightening; frightening
金属拉伸试验时,试样发生断裂,将两部分拼接后测量的标距为()。
A.总延伸标距
B.断裂总延伸率
C.断后标距
D.断后弹性标距