MRI横断面可清楚显示以下哪种结构（）
A.眶底
B.上颌窦分界
C.上颌窦前后壁
D.筛窦
E.上颌窦底
参考答案：C
确定此病最灵敏的指标是
A．血涂片，中性粒细胞多分叶现象B．血清铁蛋白测定C．骨穿及骨髓象分析D．MCV、MCH、MCHCE．血清维生素B12测定
There was a fire in the hotel around midnight last Friday. Luckily, it was soon .
A．turned on
B．turned off
C．put on
D．put out
