RT Journal Article SR Electronic T1 Deoxyribonuclease in the Treatment of Purulent Bronchitis JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP 295 OP 300 DO 10.1136/thx.8.4.295 VO 8 IS 4 A1 P. C. Elmes A1 J. C. White YR 1953 UL http://thorax.bmj.com/content/8/4/295.abstract AB