31 Miyoshi, S. Flexman, J. A. Cross, D. J. Maravilla, K. R. Kim, Y. Anzai, Y. Oshima, J. Minoshima, S. 2005 Transfection of Neuroprogenitor Cells with Iron Nanoparticles for Magnetic Resonance Imaging Tracking: Cell Viability, Differentiation, and Intracellular Localization Springer 7 286-295