1Department of Clinical Physiology and Nuclear Medicine, Center of Functional and Diagnostic Imaging and Research, Copenhagen, Denmark
2Gastro Unit, Medical Department, Hvidovre Hospital, Hvidovre, Denmark
3Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
4Department of Clinical Biochemistry, Rigshospitalet, Copenhagen, Denmark
5Department of Medicine I, Bispebjerg Hospital, Copenhagen, Denmark
6Clinical Research Centre, Hvidovre Hospital, Copenhagen, Denmark