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: CONCLUSIONS : CBDCA is neurotoxic in our model , and the type of pathological changes it induces are so closely similar to those caused by CDDP that it is probable that neurotoxicity is induced in the two drugs by the same mechanism .
### Output Text:
CONCLUSIONS : <span class="chemical">CBDCA</span> is neurotoxic in our model , and the type of pathological changes it induces are so closely similar to those caused by <span class="chemical">CDDP</span> that it is probable that neurotoxicity is induced in the two drugs by the same mechanism . 