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 conclusion , reductions in creatinine clearance and renal amphotericin B accumulation after chronic amphotericin B administration were enhanced by salt depletion and attenuated by sodium loading in rats .
### Output Text:
In conclusion , reductions in <span class="chemical">creatinine</span> clearance and renal <span class="chemical">amphotericin B</span> accumulation after chronic <span class="chemical">amphotericin B</span> administration were enhanced by salt depletion and attenuated by <span class="chemical">sodium</span> loading in rats . 