Genji Imokawa 2021. Hyaluronan in the Skin: Mechanisms of Age-Dependent and UVA-Provoked Down-Regulated Secretion of Hyaluronan by Human Dermal Fibroblasts and Prospective Agents to Ameliorate the Hyaluronan Deficiency in Chronologically Aged Skin and Photo-aged Skin. Hyaluronan in the Skin: Mechanisms of Age-Dependent and UVA-Provoked Down-Regulated Secretion of Hyaluronan by Human Dermal Fibroblasts and Prospective Agents to Ameliorate the Hyaluronan Deficiency in Chronologically Aged Skin and Photo-aged Skin. (Nov. 2021), 1–93. DOI:https://doi.org/10.9734/bpi/mono/978-93-5547-382-0.