牙周基础治疗的目的在于
A．改正不良的骨外形
B．截除病变牙根
C．固定松动牙
D．修复缺失牙，恢复咀嚼功能
E．消除致病因素
参考答案：E
The chief manger, together with all the construction workers, _______ working on the bridge day and
night to finish it before the storm season comes.
A. was
B. were
C. is
D. are
前列腺癌MRI表现，叙述错误的是（）
A.癌结节多位于边缘区
B.T1WI呈低信号，T2WI呈高信号
C.诊断主要靠T1WI
D.诊断主要靠T2WI
E.增强扫描癌结节轻度强化
