test tubes in modern scientific university office - urine quality test for covid-2019 or cystine, medical 3d

2019 acid analysis analyzing ascorbic bilirubin calcium concept control crystalline crystals diagnosis discovery disorders drink epithelial equipment experiment flask glucose gravity illustration ketones leucine medicine metabolic nitrite orange pee piss quality rendering research safety sample scientific study test tract urates urea uric urinalysis urinary urine vials virus yellow