... (Kojima et al. 1991,;Yaoita et al. 1990,), gene expression of nerve growth fac-tor (Koyama et al. 1996,; Koyama et al. 1997,) andneural and osteogenic differentiation (Kimura et al. 1998,; Mie et ... at the end of the articleKumagai et al. AMB Express 2011, 1:23 http://www .amb- express. com/content/1/1/23© 2011 Kumagai et al; licensee S pringer. This is an Open Access article distributed under ... shown in the polygonal line graph. Data represent thegeometric mean ± standard deviation of duplicate determinations.Kumagai et al. AMB Express 2011, 1:23 http://www .amb- express. com/content/1/1/23Page...