患者74岁,不慎跌伤,X线片示为无牙颁,下颌骨体部骨折移位,急症治疗应首选()
A.口外牵引
B.颌间固定
C.单颌结扎
D.颌间牵引
E.不锈钢针固定
参考答案:E
The old man sat in front of the television every evening, happy ___ anything that happened to be on.
[ ]
A. to watch
B. watching
C. watched
D. to have watched
数据库系统中实现各种数据管理功能的核心软件是______。