Kazan medical journalKazan medical journal0368-48142587-9359Eco-Vector7204210.17816/kazmj72042Research ArticleSignificance of the study of sialic acid in the blood serum to identify the activity of the rheumatic processKlyucharevaS. G.info@eco-vector.comKazan Medical Institute150619614237102306202123062021Copyright © 2021, Klyuchareva S.G.2021<p>The defeat of the connective tissue in collagen diseases is, as is known, in the destruction of the collagen complex with pathological release of proteins, polysaccharides, mucoproteins into the blood.</p>Kazan Medical archiveКазанский медицинский архив