1. A medical product containing individually or together: (1) N-acetyl-L-cysteine at a dose of 5-45 mg / kg / day； (2) selenium in the form of selenomethionine at a dose of 0.4-1.2 μg / kg / day and (3) melatonin at a dose of 0.02-0.08 mg / kg / day / or their physiologically acceptable salts. 2. The medical product according to claim 1 for simultaneous, sequential or separate combination administration to a mammal. The medical product according to claim 2, in which components (1), (2) and (3) are intended for oral administration. The medical product according to claim 1, which is a pharmaceutical composition containing the components (1) N-acetyl-cysteine, (2) selenomethionine and (3) melatonin. The medical product according to claim 1, wherein the components (1) N-acetyl-cysteine, (2) selenomethionine and (3) melatonin are intended for application to the skin. The medical product according to claim 5, in which component (1) is intended for administration at a concentration of 3-10% wt., Component (2) is intended for administration at a concentration of 0.3-1% wt. and component (3) is intended for administration at a concentration of 0.01-0.2% by weight. 7. A medical product according to any one of claims 1 to 6 for the treatment of benign or malignant neoplasia. A medical product according to any one of claims 1 to 6 for the treatment of dermatological diseases. A medical product according to any one of claims 1 to 6 for cosmetic skin treatment. 10. The medical product according to claim 1 for use as an antibacterial agent with a medical device adapted for use in contact with body fluids. The medical product of claim 10, wherein the components (1) N-acetyl-L-cysteine, (2) selenomethionine and (3) melatonin are contained in a hydrogel coating for a medical device. The medical product of claim 10 or 11, further comprising �1. Медицинский продукт, содержащий по отдельности или вместе:(1) N-ацетил-L-цистеин в дозе 5-45 мг/кг/сутки；(2) селен в форме селенометионина в д
