Changes in fasting and prandial gut and adiposity hormones following vertical sleeve gastrectomy or roux-en-y-gastric bypass: An 18-month prospective study - Alamuddin, N; Vetter, M L; Ahima, R S; Hesson, L; Ritter, S; Minnick, A; Faulconbridge, L F; Allison, K C; Sarwer, D B; Chittams, J; Williams, N N; Hayes, M R; Loughead, J W; Gur, R; Wadden, T A (Obes Surg, 2016)