[Effect of flights of varying duration on the blood protein makeup of cosmonauts].

After space flights of varying duration different adaptive changes in the protein composition of cosmonaut's blood were detected. A short-term 2-day flight induced a decline of gamma-globulin (immunoglobulins G and A) and beta 2-glycoprotein fractions. Longer-term 16- and 18-day flights caused an increase in albumin and most globulin fractions. A long-duration 49-day flight brought about an increase in the content of C3c- and C4-factors of the complement and immunoglobulins G, A and M. Return of the blood protein composition to the normal after prolonged space flights takes a long period of time.