[1] Rush Univ, Rush Presbyterian St Lukes Med Ctr, Dept Neurol Sci, Chicago, IL 60612 USA
[2] Pharmacia Inc, Columbus, OH USA
[3] Novartis Pharmaceut, E Hanover, NJ USA
[4] GlaxoSmithKline, Res Triangle Pk, NC USA
[5] Merck & Co Inc, Whitehouse Stn, NJ USA