Early abnormalities of vascular and cardiac autonomic control in Parkinson's disease without orthostatic hypotension. - Barbic, Franca; Perego, Francesca; Canesi, Margherita; Gianni, Michela; Biagiotti, Sara; Constantino, Giorgio; Pezzoli, Giovanni; Porta, Alberto; Malliani, Alberto; Furlan, Raffaello; Costantino, Giorgio (Hypertension (0194911X), 2007)