原发性支气管肺癌的致病因素有()
A．吸烟
B．大气污染
C．结核瘢痕
D．物理化学因素刺激
E．饮酒
参考答案：A, B, C, D
_______ into many languages, Harry Potter is popular with children and adults as well all over the world. [ ]
A. Having been translated
B. Being translated
C. Having translated
C. To be translated
心绞痛疼痛发作时的典型心电图表现是
A．ST段压低>0.1mV，T波低平或倒置B．出现宽大畸形的病理性Q波C．P-R间期延长D．心肌缺血改变，ST段抬高E．T波高尖
