Affiliation: | 1. Service de Pédiatrie, Centre Hospitalier Universitaire Vaudois, 1011 Lausanne, USA;2. Department of Neuropathology, Institute of Pathology, University of Zürich, 8091 Zürich Switzerland;3. Department of Neurology, Johns Hopkins Medical School, Baltimore, Md. 21205, USA;4. Department of Animal Sciences, School of Agriculture, Purdue University, Lafayette, Ind. 49707 U.S.A. |