Retinol-binding protein 4 and insulin resistance in lean, obese, and diabetic subjects - Graham, T E; Yang, Q; Bluher, M; Hammarstedt, A; Ciaraldi, T P; Henry, R R; Wason, C J; Oberbach, A; Jansson, P-A; Smith, U; Kahn, B B (N Eng J Med, 2006)