[1] Mayo Clin, Dept Neurol, Scottsdale, AZ 85269 USA
[2] Thomas Jefferson Univ, Jefferson Med Coll, Philadelphia, PA 19107 USA
[3] So Illinois Univ, Springfield, IL USA
[4] Harvard Univ, Sch Med, Boston, MA USA
[5] Cornell Med Sch, New York, NY USA
[6] Univ Washington, Seattle, WA 98195 USA
[7] Univ Kentucky, Lexington, KY 40506 USA
[8] Univ Arizona, Tucson, AZ USA
[9] Rush Univ, Chicago, IL 60612 USA
[10] Neurol Clin Texas, Dallas, TX USA
[11] New Jersey Neurosci Inst, Edison, NJ USA
[12] Univ Oklahoma, Oklahoma City, OK USA
[13] Med Coll Wisconsin, Madison, WI USA
[14] Wake Forest Univ, Winston Salem, NC 27109 USA
[15] Jacksonville Neurol Clin, Jacksonville, FL USA
[16] Univ Florida, Gainesville, FL USA
[17] Univ S Dakota, Sioux Falls, SD USA