- Normal values and age-dependent changes in GTP cyclohydrolase I activity in stimulated mononuclear blood cells measured by high-performance liquid chromatography. Hibiya, M., Ichinose, H., Ozaki, N., Fujita, K., Nishimoto, T., Yoshikawa, T., Asano, Y., Nagatsu, T. J. Chromatogr. B Biomed. Sci. Appl. (2000)









