. 2008 Mar 10;2:29–37. doi: 10.2174/1874091X00802010029
2008 Bentham Science Publishers Ltd.
This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.5/), which permits unrestrictive use, distribution, and reproduction in any medium, provided the original work is properly cited.