RT Journal Article SR Electronic T1 Vitamin D3 and response to glucocorticoids in steroid resistant asthmatics JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP 375 OP 375 DO 10.1136/thx.2006.la0200 VO 61 IS 5 A1 S Kon YR 2006 UL http://thorax.bmj.com/content/61/5/375.abstract AB