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The stratum granulosum (or granular layer) is a thin layer of cells in the epidermis.〔James, William; Berger, Timothy; Elston, Dirk (2005) ''Andrews' Diseases of the Skin: Clinical Dermatology'' (10th ed.). Saunders. Page 2. ISBN 0-7216-2921-0.〕 Keratinocytes migrating from the underlying stratum spinosum become known as granular cells in this layer. These cells contain keratohyalin granules, which are filled with histidine- and cystine-rich proteins that appear to bind the keratin filaments together. Therefore, the main function of keratohyalin granules is to bind intermediate keratin filaments together.〔Marks, James G; Miller, Jeffery (2006). ''Lookingbill and Marks' Principles of Dermatology'' (4th ed.). Elsevier Inc. Page 7. ISBN 1-4160-3185-5.〕 At the transition between this layer and the stratum corneum, cells secrete lamellar bodies (containing lipids and proteins) into the extracellular space. This results in the formation of the hydrophobic lipid envelope responsible for the skin's barrier properties. Concomitantly, cells lose their nuclei and organelles causing the granular cells to become non-viable corneocytes in the stratum corneum.〔 ==Additional images== Image:Normal Epidermis and Dermis with Intradermal Nevus 10x.JPG|Epidermis and dermis of human skin Image:Skinlayers.png|Section of epidermis 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Stratum granulosum」の詳細全文を読む スポンサード リンク
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