TY - CHAP M1 - Book, Section TI - Chapter 16. Disorders of Cellular Growth, Differentiation, & Maturation A1 - Chandrasoma, Parakrama A1 - Taylor, Clive R. PY - 1998 T2 - Concise Pathology, 3e AB - The cells of the body continue to grow, divide, and differentiate throughout life. Normally, growth and differentiation are controlled in such a way as to maintain the normal structure of a particular tissue. In tissues characterized by continuous cell loss (skin, intestinal mucosa, blood), labile stem cells continuously undergo mitosis to replace lost cells. Stem cells frequently differentiate from a primitive to a mature form during this process—eg, normoblasts in bone marrow become the erythrocytes of the peripheral blood. In the skin, as superficial keratinized cells are shed from the surface, basal cells proliferate at a suitable rate to replace them. The newly produced basal cells move upward, differentiating into squamous cells that undergo nuclear and cytoplasmic changes to become the superficial cornified layer of cells. When the epidermal turnover rate is normal, the skin appears normal on histologic examination; but if the rate is greatly increased, as occurs in psoriasis, cells do not fully mature, and abnormalities are seen both on gross examination and at the histologic level. SN - PB - The McGraw-Hill Companies CY - New York, NY Y2 - 2024/03/28 UR - accessphysiotherapy.mhmedical.com/content.aspx?aid=185466 ER -