Diagnostics and treatment of non-alcoholic fatty liver disease: clinical guidelines of the Russian Scientific Liver Society and the Russian gastroenterological association - V. T. Ivashkin; Marina V. Mayevskaya; Ch. S. Pavlov; I. N. Tikhonov; Ye. N. Shirokova; A. O. Buyeverov; O. M. Drapkina; Yu. O. Shulpekova; V. V. Tsukanov; S. N. Mammayev; I. V. Mayev; L. K. Palgova (Российский журнал гастроэнтерологии, гепатологии, колопроктологии)