Inclusion Criteria:  diagnosis of a first-ever stroke verified by computed tomography (CT) or magnetic resonance imaging (MRI) reports admitted to the hospital for standard neurorehabilitation within 1 to 6 months of stroke onset healthy individuals (for control group)  Exclusion Criteria:  significant acute medical illness (e.g., autoimmune disease, infection, tumor, heart failure, renal or liver dysfunction) significant acute neurological illness other than stroke (e.g., head trauma, brain abscess, brain tumor, migraine attack, seizure) cannot adapt to work previous history of neurorehabilitation therapy taking the antioxidant supplements