Christensen T, Riis AH, Hatch EE, Wise LA, Nielsen MG, Rothman KJ, Toft Sorensen H, Mikkelsen EM. Costs and efficiency of online and offline recruitment methods: a web-based cohort study. J Med Internet Res. 2017 Mar 1;19(3):e58. doi: 10.2196/jmir.6716
Gallego R, Codony-Servat J, Garcia-Albeniz X, Carcereny E, Longaron R, Oliveras A, Tosca M, Auge JM, Gascon P, Maurel J. Serum IGF-I, IGFBP-3, and matrix metalloproteinase-7 levels and acquired chemo-resistance in advanced colorectal cancer. Endocr Relat Cancer. 2009 Mar;16(1):311-7. doi: 10.1677/ERC-08-0250