Endogenous opioid release in pathological gamblers after an oral amphetamine challenge: a [11C]carfentanil PET study - Mick, I; Myers, J; Stokes, P; Colasanti, A; Erritzoe, D; Searle, G; Gunn, R; Rabiner, I; Lingford-Hughes, A; Nutt, D (ELSEVIER SCIENCE BV, 2014)