Afta

Afta (aphthae; Greek aphthai – ulcerations, rashes in an oral cavity) – small areas of a superficial necrosis of an epithelium of mucous membranes in the form of small ulcers with a bright red inflammatory rim or yellowish-gray roundish erosion.

 
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The liver is the heaviest body in our body. Its average weight makes 1,5 kg.