1. Division of Biomedical Radiation Sciences, Department of Oncology, Radiology and Clinical Immunology, Rudbeck Laboratory, Uppsala University, S-751 85, Uppsala, Sweden
2. Division of Radiology, Department of Oncology, Radiology and Clinical Immunology, Rudbeck Laboratory, Uppsala University, S-751 85, Uppsala, Sweden
3. Division of Biomedical Radiation Sciences, Department of Oncology, Radiology and Clinical Immunology, Rudbeck Laboratory, Uppsala University, S-751 85, Uppsala, Sweden
4. Nuclear Physics Institute, Rez near Prague, 250 68, Czech Republic