Fig. 4From: Systemic analysis of urinary stones from the Northern, Eastern, Central, Southern and Southwest China by a multi-center studyNitrogen and calcium distribution in uric acid and uric acid- calcium oxalate mixed crystals (the red dot represented element distribution). a Uric acid crystals: A1. The energy spectrum, A2. Nitrogen distribution; b Uric acid- calcium oxalate mixed crystals: B1. The energy spectrum, B2. Nitrogen distribution, B3. Calcium distributionBack to article page