Decreased Microglial Activation Precedes Stabilization of Disability in Multiple Sclerosis Patients Treated with Natalizumab - Politis, M; Giannetti, P; Niccolini, F; Su, P; Turkheimer, F; Waldman, A; Reynolds, R; Nicholas, R; Piccini, P (LIPPINCOTT WILLIAMS & WILKINS, 2013)