Effects of hypoxia inducible factor-1 alpha small interfering RNA on hypoxia inducible factor-1 alpha, stromal derived factor 1 alpha and vascular endothelial growth factor gene expression in bone marrow mesenchymal stem cells  Chinese Journal of Tissue Engineering Research . 2010, (36): 6759 -6763 .  DOI: 10.3969/j.issn.1673-8225.2010.36.024