单项选择题
Which of the following tissues based strictly on spindensity should appear the darkest? ( )
A.fat B.muscle C.water D.bone
多项选择题 椎体外伤性压缩骨折的X线表现有()
单项选择题 关于移动因素与照片影像关系的叙述，错误的是()
单项选择题 CT扫描，消化管阳性对比剂通常为()
