RT Journal Article SR Electronic T1 Clinical Features and Perforin A91V Gene Analysis in 31 Patients with Macrophage Activation Syndrome and Systemic Juvenile Idiopathic Arthritis in China JF The Journal of Rheumatology JO J Rheumatol FD The Journal of Rheumatology SP 1238 OP 1239 DO 10.3899/jrheum.121040 VO 40 IS 7 A1 ZENG HUASONG A1 WEI PING A1 CHEN XIANGYUAN A1 WEI YANDAN YR 2013 UL http://www.jrheum.org/content/40/7/1238.abstract AB