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 this study , three Chinese patients with ticlopidine - induced aplastic anemia were reported and another 13 patients in the English literature were reviewed .
### Output Text:
In this study , three Chinese patients with <span class="chemical">ticlopidine</span> - induced aplastic anemia were reported and another 13 patients in the English literature were reviewed . 