18 citations
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January 1994 in “Skin pharmacology and physiology” Sunlight damages hair, causing cuticle loss, protein changes, and discoloration.
45 citations
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December 2006 in “Biopolymers” Permanent waving weakens hair by altering its protein structure.
12 citations
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January 2014 in “Cell structure and function” Different combinations of human hair keratins affect how hair fibers form.
4 citations
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July 2010 in “International Journal of Cosmetic Science” Curved human hair has different structures on its convex and concave sides.
4 citations
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January 1981 in “PubMed” Hair medullary cells in mammals vary in complexity, with humans having more structured cells similar to inner root sheath cells.