[1] Univ Michigan, Med Ctr, Dept Neurol, Ann Arbor, MI 48109 USA
[2] Mayo Clin, Dept Neurol, Rochester, MN 55905 USA
[3] Natl Hosp Neurol & Neurosurg, Dept Neurol, London WC1N 3BG, England
[4] Univ Cattolica, Ist Neurol, Dept Neurol, I-00168 Rome, Italy
[5] Dept Social Med, Bristol BS8 2P, Avon, England
[6] Mt Sinai Med Ctr, Dept Neurol, New York, NY 10029 USA
[7] Univ Bonn, Dept Neurol, D-53105 Bonn, Germany
[8] Toronto Western Hosp, Dept Neurol, Toronto, ON MP11 304, Canada
[9] Inst Psychiat, Dept Neuropathol, London SE5 8AF, England
[10] NINDS, NIH, Bethesda, MD 20892 USA
[11] St Marys Hosp, Pickering Unit, Imperial Coll Sch Med St Marys, Dept Neurovasc Med, London W2 1NY, England
[12] Vanderbilt Univ, Dept Pharmacol, Nashville, TN 37232 USA
[13] Vanderbilt Univ, Dept Neurol, Nashville, TN 37232 USA
[14] Univ Hawaii Manoa, Dept Med, Honolulu, HI 96813 USA
[15] Univ Innsbruck, Neurol Klin, A-6020 Innsbruck, Austria