1870-199X 1870-199X S1870-199X2010000100015 Mexico Mexico Mexico 00 00 2010 00 00 2010 14 1 15 20

2002 66 6 6 766-72 2002 81 8 8 531-5 2000 97 25 25 13625-30 2003 82 12 12 976-81 2003 100 5807-12 2006 41 547-53 2005 8 191-9 2004 364 149-55 2002 81 531-5 2005 8 54-9 2001 29 6 6 532-9 1999 14 1 1 47-56 1999 14 8 8 1345-56 2001 19 180-92 2006 419 99-113 1999 10 79-98 1993 90 8562-5 1995 57 52-9 2000 19 615-22 2004 83 590-5 National Institutes of Health