title: Serum protease inhibitor levels in smokers.
mesh_terms: D000328:Adult; D006801:Humans; D008297:Male; D008875:Middle Aged; D011480:Protease Inhibitors / Q000097:blood*; D011656:Pulmonary Emphysema / Q000201:enzymology; D012306:Risk; D012907:Smoking
chemical_list: D011480:Protease Inhibitors