RT Journal Article SR Electronic T1 Serum branched-chain amino acid to histidine ratio: a novel metabolomic biomarker of knee osteoarthritis JF Annals of the Rheumatic Diseases JO Ann Rheum Dis FD BMJ Publishing Group Ltd and European League Against Rheumatism SP 1227 OP 1231 DO 10.1136/ard.2009.120857 VO 69 IS 6 A1 Guangju Zhai A1 Rui Wang-Sattler A1 Deborah J Hart A1 Nigel K Arden A1 Alan J Hakim A1 Thomas Illig A1 Tim D Spector YR 2010 UL http://ard.bmj.com/content/69/6/1227.abstract AB Markup server — Error Error There was a problem handling your request. Please try again in a few minutes, or contact us if you continue to experience this problem.