PPARA and rheumatoid arthritis: The occurrence and development of SZ realted with a multi-indicator diagnostic model of SZ reflect TCM characteristics are established with LysoPA (20:3(5Z,8Z,11Z)/0:0), Prostaglandin E2, Leukotriene B4, Lithocholate 3-O-glucuronide, 3-Hydroxyquinine, Lithocholic acid glycine conjugate and PA(18:0/22:6(5Z,8E,10Z,13Z,15E,19Z)-2OH(7S, 17S) as diagnostic indicators, Which associated with 6 key pathways, such as Pathogenic Escherichia coli infection, Rheumatoid arthritis, PPAR signaling pathway, Bile secretion, GnRH signaling pathway, Fat digestion and absorption.