下列哪项引起的呕吐为中枢性呕吐
A．急性胃肠炎
B．急性胰腺炎
C．胆石症
D．癫癎持续状态
E．肠梗阻
参考答案：D
I have no time to tell you the whole story_________. In short they got married at last.
A．in need
B．in the beginning
C．in general
D．in detail
在通常可测范围内，底片衬度随底片密度的提高而（）
A、增加
B、减小
C、不变
D、无规律变化
