Lung surfactant (LS) was examined in the course of chronic bronchitis (CB) development in 25 subjects with CB risk factors (RF), 80 with prebronchitis (PB), 30 with chronic non-obstructive bronchitis (CNOB) and 45 with chronic obstructive bronchitis (COB). Biochemical study of the expirates covered total phospholipids (TP), fractions of neutral lipids… (More)