可见呕血伴慢性、周期性、节律性上腹痛的疾病是：

A．消化性溃疡
B．肝硬化门静脉高压
C．急性再生障碍性贫血
D．急性梗阻性化脓性胆管炎
E．急性传染病

Customs duties shall not be reduced or exempted on goods imported from or exported out of ______.

A．special economic zones
B．coastal eiies
C．chinese-foreign joint ventures
D．foreign wholly-owned enterprises