Bone marrow (BM) stromal cells have many of the characteristics of stem cells for differentiation into mesenchymal tissues. We have isolated mescenchymal stem cells (MSC) from BM mononuclear cells (BMNC). The cells showed a fibroblast-like morphology, but the morphology changed after 12μmol/L 5-azacytidine (5-aza). The cells gradually increased in size, lengthened in one direction and formed a stick-like morphology at one week. They connected with adjoining cells after two weeks and formed myotube-like stru...