85 citations
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  October 2007   in “International Journal of Dermatology”    Curly hair shape is due to uneven growth patterns in the hair follicle.  
     
           191 citations
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  November 1959   in “Annals of the New York Academy of Sciences”    Hair and wool have complex microscopic structures with microfibrils and varying cystine content.  
     
           40 citations
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  May 2016   in “Proceedings of the National Academy of Sciences of the United States of America”    Changes in keratin make hair follicles stiffer.  
     
           30 citations
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  April 2017   in “Journal of structural biology”    Human hair keratin fibers have a detailed nano-scale structure that changes with different conditions.  
               1 citations
,
  January 2021   in “Springer Proceedings in Materials”    Researchers developed a new method to clearly see and label hair proteins with minimal errors using advanced freezing and microscopy techniques.