(A) T3 group: The thyroid follicles were dilated (DL) and contain large amount s of colloid (CO). Also there is thickening of the interstitial tissue of thyroid (T). 10X H & E. (B) Note high dilation of thyroid follicles (DL) with large amount of colloid (CO) and these follicles lined by simple cuboidal epithelium (S). 40X H & E.