上段食管受压移位,下述疾病何种原因为常见:().
A.淋巴结肿大
B.神经源性肿瘤
C.甲状腺肿大
D.胸腺肿瘤
E.以上都不是
参考答案:C
________China has successfully launched its Shenzhou Ⅵ with two astronauts in it has shocked the world.
A.What
B.As
C.It
D.That
曲线区段承力索位置限界值为()。
A、±50mm
B、±200mm
C、允许向曲线内侧偏移150mm
D、允许向曲线外侧偏移150mm