A sensitive sandwich ELISA for measuring thrombopoietin in human serum: serum thrombopoietin levels in healthy volunteers and patients with haemopoietic disorders - Tahara, T; Usuki, K; Sato, H; Ohashi, H; Morta, H; Tsumura, H; Matsumoto, A; Miyazaki, H; Urabe, A; Kato, T (Br J Haematol, 1996)