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: All three aminoglycosides decreased GFR and increased urinary excretion of sodium and potassium .
### Output Text:
All three <span class="chemical">aminoglycosides</span> decreased GFR and increased urinary excretion of <span class="chemical">sodium</span> and <span class="chemical">potassium</span> . 