吞钡X线检查显示食管虫蚀样充盈缺损，纵行黏膜皱襞增宽
A．反流性食管炎B．食管癌C．食管静脉曲张D．贲门失弛缓症E．食管裂孔疝
参考答案：C
Great as Newton was, many of his ideas _______ today and are being modified by the work of scientists of our time.
A．are to challenge
B．may be challenged
C．have been challenged
D．are challenging
关于再沸器结焦的原因，说法正确的是（）。
A、物料的粘度大
B、再沸器温度高
C、使用时间长
D、塔的液位高
