Figure 1.

(a) Gross findings of the lung. Enlargement with an increase in the size of the organ, together with discoloration characterized by the formation of multifocal to confluent whitish, firm nodules (black arrow heads) are shown in the treated lungs. The change is prominent at 6 and 12 months after silica treatment. Saline 6M: 6 months after saline treatment (control), Silica 1M: 1 month after silica treatment, Silica 3M: 3 months after silica treatment, Silica 6M: 6 months after silica treatment, Silica 12M: 12 months after silica treatment. M: Month, and (b) ratio of the lung weight/body weight, showing increased ratio after silica treatment. M: month. All data are expressed as mean ± SD. Statistically significant differences (* p < 0.05) are indicated.