Changes of collagen protein with ageing.
D000375:Aging / Q000502:physiology*; D000818:Animals; D002807:Chondroitin; D003094:Collagen / Q000032:analysis*; D006898:Hydroxylamines; D007202:Indicators and Reagents; D051381:Rats; D012867:Skin / Q000032:analysis
D006898:Hydroxylamines; D007202:Indicators and Reagents; D002807:Chondroitin; D003094:Collagen