In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: At autopsy , analysis of liver parenchyma revealed rich portal inflammatory infiltrate , which consisted of mixed eosinophil and monocyte cells , associated with several foci of necrosis surrounded by a hard ring of non - specific granulomatous tissue .
### Output Text:
At autopsy , analysis of liver parenchyma revealed rich portal inflammatory infiltrate , which consisted of mixed eosinophil and monocyte cells , associated with several foci of necrosis surrounded by a hard ring of non - specific granulomatous tissue . 