Amyloid-β protein oligomerization and the importance of tetramers and dodecamers in the aetiology of Alzheimer's disease. by Bernstein, S, Dupuis, N, Lazo, N, Wyttenbach, T, Condron, M, Bitan, G, Teplow, D, Shea, J, Ruotolo, B, Robinson, C, Bowers, M