Serum FGF21 Levels Are Increased in Obesity and Are Independently Associated With the Metabolic Syndrome in Humans - Zhang, X; Yeung, DC Y; Karpisek, M; Stejskal, D; Zhou, Z-G; Liu, F; Wong, RL C; Chow, W-S; Tso, AW K; Lam, KS L; Xu, A (Diabetes, 2008)