1. From the Department of Health Sciences Research (V.L.F., D.O.W., W.M.O., J.P.W.) and the Division of Cerebrovascular Diseases (D.O.W., W.M.O., J.P.W.), Mayo Clinic and Mayo Foundation, Rochester, Minn; and the Cerebrovascular Disease Center, Institute of Internal Medicine Siberian Branch of the Russian Academy of Medical Science, Novosibirsk, Russia (V.L.F., Y.P.N.).