真皮(国外英文资料).doc

真皮(国外英文资料) Sir, dermal profile The dermis is located deep in the epidermis, down and subcutaneous tissue, and there is no clear boundary with the latter. The dermis consists of dense connective tissue. It contains a variety of connective tissue cells and a large number of collagen fibers, elastic fibers, so that the skin is both flexible and resilient. Connective tissue cells are more fibroblasts and mast cells. Dermis thickness is different, palms, soles of the dermis is thicker, about 3mm above, eyelid and so on, the thinnest, about 0.6mm. The average thickness is between 1 and 2mm. The dermis can be divided into papillary layer and reticular layer. Located between the epidermis and dermis subcutaneous tissue, mainly composed of collagen fibers, elastic fibers and reticular fibers and amorphous matrix of connective tissue, including nerve and nerve endings, blood vessels, lymphatic vessels, muscles and skin appendages. The dermis can be divided into two layers, the nipple layer and the reticular layer. The papillary layer can be divided into dermal papilla and papillary layer (both collectively referred to as the upper dermis). The mesh layer can also be divided into the central dermis and the lower dermis, but there is no definite boundary between the two. The collagen fibers and elastic fibers of the dermal connective tissue are intertwined and buried in the stroma. The cells in normal dermis include fibroblasts, tissue cells and mast cells. Collagen fibers, elastic fibers and stroma are secreted by fibroblasts. Reticular fibers are immature collagen fibers, not an independent component. The thickness of dermis and fibrous tissue and matrix is closely related to how much, and compactness, skin plumpness, relaxation and wrinkling are closely related, has attracted more and more attention in recent years, scientists in cosmetic dermatology. [edit this paragraph] Dermal composition 1. collagen fiber It is the most abundant component in the dermis connective tissue.