External Quality Assessment of Trans-European Multicentre Antigen Determinations (Enzyme-Linked Immunosorbent Assay) of Urokinase-Type Plasminogen Activator (uPA) and Its Type 1 Inhibitor (PAI-1) in Human Breast Cancer Tissue Extracts

British Journal of Cancer - United Kingdom
doi 10.1038/bjc.1998.704