[名词解释] 房室传导阻滞(AVblock)

充血性心力衰竭(CongestiveHeartFailure) 中纵隔最常见的肿瘤是() ["A．胸内甲状腺肿","B．神经源性肿瘤","C．胸腺瘤","D．淋巴瘤","E．畸胎瘤"] 潜伏青紫型先心病 粉尘导致尘肺的发病作用是() ["A．超敏反应","B．致癌作用","C．中毒作用","D．致纤维化作用","E．局部刺激作用"] R-on-T现象 房室传导阻滞(AVblock)