RT Journal Article SR Electronic T1 Asthma: is there an airway receptor barrier? JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP 773 OP 776 DO 10.1136/thx.51.8.773 VO 51 IS 8 A1 B. A. Hills YR 1996 UL http://thorax.bmj.com/content/51/8/773.abstract AB