慢性阻塞性肺疾病（COPD）患者的支气管肺泡灌洗液和血浆中肿瘤坏死因子－α（TNF-α）的浓度明显高于正常人。近年来，发现机体TNF-α水平受遗传控制，研究证实TNF-α水平与TNF-α基因启动子片段多态性相关。本研究使用气浴式DNA扩增仪，采用聚合酶链式反应（PCR）和限制性片 Bronchoalveolar lavage fluid and plasma levels of tumor necrosis factor-α (TNF-α) in patients with chronic obstructive pulmonary disease (COPD) were significantly higher than those in normal subjects. In recent years, it has been found that the level of TNF-α in the body is genetically controlled. The study confirmed that TNF-α level is related to the polymorphism of TNF-α gene promoter. This study used an air bath DNA amplification instrument, using polymerase chain reaction (PCR) and restriction fragments