Figure 1From: Calcium-deficiency assessment and biomarker identification by an integrated urinary metabonomics analysis Representative ultra-performance liquid chromatography and quadrupole time-of-flight tandem mass spectrometry (UPLC/Q-TOF MS/MS)-based peak intensity chromatogram of rat urine in electrospray ionization (ESI) negative ion mode. (A) Rat on normal-calcium diet; (B) rat on low-calcium diet. BPI, baseline peak intensity.Back to article page