experiments on albino rats showed that polyvinylpyridine-n-oxide ( pvno ) inhalations ( mol . mass 2000 ; 9.8 +/- 1.2 and 99 +/- 4 mg/m3 for 7 months ) slowed down the course of silicosis developing with a gradual entrance and uniform distribution of dust in the lungs , but proved little effective with a one-time introduction of a large amount of `` '' aggressive '' '' dust because of the difficulty for the drug to reach and penetrate the sclerosed sections of the tissue .
C0037116
silicosis
C0024109
lungs