关于X线产生应具备的条件，以下哪项是错误的（）。
A.电子云
B.高真空
C.电子的高速运动
D.阳极靶
E.电子的骤然加速
参考答案：E
血小板粘附率增高可见于血管性血友病。()
__________，I have to put it away and focus my attention on study this week.
A．However the story is amusing
B．No matter amusing the story is
C．However amusing the story is
D．No matter how the story is amusing
