how to get biomedical datasets
http://www.cdc.gov/nchs/
http://www.cdc.gov/nchs/datawh.htm#Data%20base%20searches
http://www.cdc.gov/nchs/datawh/ftpserv/ftpdata/ftpdata.htm
http://www.cdc.gov/nchs/about/major/nhanes/nh3data.htm#Data%20Files%201a