Background: Tobacco smoking may be the most important risk factor for chronic obstructive pulmonary disease (COPD) development. without any evidence of infection or COPD. The serum levels of TNF- were assessed by ELISA. Results: The TNF- serum levels were significantly higher for the group of smokers compared to the group of nonsmokers ( 0.004). We… Continue reading Background: Tobacco smoking may be the most important risk factor for