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: We noticed that 10 of our 35 cases of cefotetan - induced hemolytic anemias were in patients who had received cefotetan prophylactically for obstetric and gynecologic procedures .
### Output Text:
We noticed that 10 of our 35 cases of <span class="chemical">cefotetan</span> - induced hemolytic anemias were in patients who had received <span class="chemical">cefotetan</span> prophylactically for obstetric and gynecologic procedures . 