About the proof of urocanic acid in callus and in normal human horny layer.
D002145:Callosities; D002845:Chromatography; D006801:Humans; D007093:Imidazoles; D066298:In Vitro Techniques; D012867:Skin; D013057:Spectrum Analysis; D014466:Ultraviolet Rays
D007093:Imidazoles