. 2006 Apr 24;5:25. doi: 10.1186/1475-925X-5-25
Copyright © 2006 Gao et al; licensee BioMed Central Ltd.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.