Bariatric SurgeryObesity, MorbidGastroplastyGastric BypassGastrectomyAnastomosis, Roux-en-YWeight LossLaparoscopyTreatment OutcomeBariatric MedicineBiliopancreatic DiversionObesityJejunoileal BypassBariatricsPreoperative PeriodAvitaminosisPostoperative ComplicationsHyperoxaluriaBody Mass IndexPostoperative Period