IncretinsGastric Inhibitory PolypeptideGlucagon-Like Peptide 1Diabetes Mellitus, Type 2Diabetes Mellitus, Type 1Dipeptidyl-Peptidase IV InhibitorsDiabetes MellitusDipeptidyl Peptidase 4Glucagon-Like PeptidesReceptors, GlucagonBlood GlucoseDiabetes ComplicationsHypoglycemic AgentsInsulinGastric BypassGlucagonInsulin-Secreting CellsDiabetes Mellitus, ExperimentalObesity, MorbidBariatric SurgeryGlucose Tolerance TestGlucoseDiabetes, GestationalPostprandial PeriodHemoglobin A, GlycosylatedDiabetes InsipidusRisk FactorsHyperglycemia