3[2]Houlfeld J, Hamm H. The role of pulmonary surfactant in obstructive airway disease [J]. European Respirratory Journal. 1997,10: 482 ~491.
4[4]Fraschini. Effects of a mucolytic agent on the bioavaility of antibiotics in patients with chronic respiratory disease [J]. Current Therapeutic Research. 1997,2 (5) :9.
5[5]Kondo T, Tagami S, Yoshieka A, et al. Current smoking of elderly men reduces antioxidants in alveolar macrophages. Am J Respir Crit Care Med. 1994:149 ~ 178.
6[6]Anonymous. Prevention of chronic exacerbations with ambroxol( mucosolvan retard) -an open,long-term study n 5635 patients. Respiration.1989:55 ~ 84.