Atopic dermatitis(AD)is a chronic, recurrent and inflammatory skin disease commonly seen clinically.In recent years, the incidence of AD in the elderly population has gradually increased.Due to factors such as aging and underlying diseases, AD in the elderly exhibits unique features in etiology, pathogenesis, and clinical manifestations, which also pose certain difficulties in its diagnosis and treatment.This article reviews research progress related to the definition, etiology, pathogenesis, clinical manifestations and treatment of AD in the elderly.

OBJECTIVE： To study the chemical constituents of ethyl acetate fraction of Panax ginseng fungal substance obtained by biotransformation， in order to obtain compounds with better activity and lower toxicity， and to provide reference for new drug R&D and the second development and utilization of P. ginseng. METHODS： Fungus of Code Name C-1 seed solution was added into the culture medium containing P. ginseng， and P. ginseng fungal substance was obtained by biotransformation； the dried P. ginseng fungal substance were weighed， extracting with 70％ ethanol solvent and concentrating to obtain thick paste. The thick paste was added with water suspension and extracted with ethyl acetate to obtain ethyl acetate fraction. TLC， silica gel column chromatography， ODS column chromatography and semi-prepared liquid phase were used to isolate and purify above ethyl acetate fraction， and the compound structure was identified according to physicochemical properties， hydrogen spectrum （1H-NMR） and carbon spectrum （13C-NMR） data. RESULTS： Eight compounds were isolated and identified from the ethyl acetate fraction of P. ginseng fungal substance and identified as ginsenoside Rs7 （1）， ginsenoside Rk3 （2）， oleanolic acid-28-O-β-D-glucopyranoside （3）， ginsenoside Rs6 （4）， 20（R）-ginsenoside Rh1 （5）， ginsenoside F1 （6）， notoginsenoside R2 （7） and ginsenoside F4 （8）. CONCLUSIONS： All the above compounds were found in P. ginseng fungal substance， which compounds 3， 5， 6， 7 and 8 were obtained after biotransformation， proving that biotransformation technology can change the chemical composition of ginseng.