1. Department of Gastroenterology, Medical Section, Herlev Hospital, University of Copenhagen, Denmark, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Centre for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, The Chinese Academy of Sciences, PR China, Department of Biomolecular Medicine, Imperial College London, United Kingdom, and Department of Cellular and Molecular Medicine, The Panum Institute, University of Copenhagen, Denmark