tokens: Collagen was extracted from the skin , and the lack of type III collagen was determined by means of sodium dodecyl sulfate-polyacrylamide gel electrophoresis ( SDS-PAGE ) .
folded_tokens: Collagen be extract from the skin , and the lack of type iii collagen be determine by means of sodium dodecyl sulfate-polyacrylamide gel electrophoresis ( sds-page ) .