PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 2721585-4 1989 Cultivation of the cells at the optimum growth-stimulating concentration (500 microM) of ferric citrate resulted in an intracellular iron level about 100-fold higher than that of cells cultivated at the optimum transferrin concentration (5 micrograms/ml). ferric citrate 89-103 serotransferrin Bos taurus 211-222