EVALUATION OF MAINTENANCE OF PATIENTS WITH CHRONIC OBSTRUCTIVE LUNG DISEASE AIMED AT HOSPITALIZATION IN PULMUNOLOGIC DEPARTMENTS OF KAZAN oleh A. A. Vizel, I. N. Salakhova, I. Y. Vizel, A. R. Vafina, V. I. Ilyinsky, E. Z. Kudryavtseva, V. A. Sergeev