Functional and morphological maturation of implanted neonatal cardiomyocytes as a comparator for cell therapy. by Sato, M, Carr, C, Stuckey, D, Ishii, H, Kanda, G, Terracciano, C, Siedlecka, U, Tatton, L, Watt, S, Martin-Rendon, E, Clarke, K, Harding, SE