1. National Institutes of Health, Bethesda Section on Medical Neuroendocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, , MD, 20892-1109 , USA
2. Department of Nuclear Medicine, Aix-Marseille University, La Timone University Hospital , 13385 Marseille , France
3. Molecular Imaging Branch, National Cancer Institute, National Institutes of Health , Bethesda, MD, 20892 , USA