颈椎病发生和发展中最基本的原因是
A．急性损伤
B．慢性劳损
C．颈椎间盘突出
D．先天性椎管狭窄
E．颈椎间盘退行性变
参考答案：E
Hill often attends lectures at Nanjing University , chiefly ____ his knowledge about hobbies .
A．to acquire
B．for improving
C．to advance
D．by increasing
牙髓充血与急性浆液性牙髓炎的鉴别要点是（）
A.有无探痛
B.有无叩痛
C.有无自发性痛
D.有无温度刺激痛
E.有无化学刺激痛
