Systems toxicology and the Chemical Effects in Biological Systems (CEBS) knowledge base. - Waters,M.; Boorman,G.; Bushel,P.; Cunningham,M.; Irwin,R.; Merrick,A.; Olden,K.; Paules,R.; Selkirk,J.; Stasiewicz,S.; Weis,B.; Van Houten,B.; et al. (EHP Toxicogenomics, 2003)