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: In all the experiments , the attenuation of the lithium - induced diabetes - insipidus - like syndrome by amiloride was accompanied by a reduction of the ratio between the lithium concentration in the renal medulla and its levels in the blood and an elevation in the plasma potassium level .
### Output Text:
In all the experiments , the attenuation of the <span class="chemical">lithium</span> - induced diabetes - insipidus - like syndrome by <span class="chemical">amiloride</span> was accompanied by a reduction of the ratio between the <span class="chemical">lithium</span> concentration in the renal medulla and its levels in the blood and an elevation in the plasma <span class="chemical">potassium</span> level . 