1. Digestive Diseases Branch; National Institutes of Health; Bethesda; MD; USA
2. Laboratory of Biological Modeling; National Institutes of Health; Bethesda; MD; USA
3. Office of the Intramural Clinical Director; National Institutes of Health; Bethesda; MD; USA
4. Office of the Director National Institute of Diabetes Digestive and Kidney Diseases, National Institutes of Health; Bethesda; MD; USA
5. Nuclear Medicine Division, Clinical Center; National Institutes of Health; Bethesda; MD; USA