1. Department of Neurology, University Hospital, S-221 85 Lund, Sweden.
2. Department of Medical Cell Research, Biskopsgatan 5, S-223 62 Lund, Sweden.
3. Department of Clinical Immunology, Karolinska Institute at Huddinge Hospital, S-141 86 Huddinge, Sweden.
4. Department of Neurosurgery, University Hospital, S-221 85 Lund, Sweden.
5. Department of Gynecology, University Hospital, S-221 85 Lund, Sweden.
6. MRC Cyclotron Unit, Hamersmith Hospital, London W12 OHS, United Kingdom.
7. Paul Scherrer Institute, Switzerland.
8. MRC Human Movement and Balance Unit and University Department of Clinical Neurology, Institute of Neurology, The National Hospital, Queen Square, London WCIN 3BG, United Kingdom.