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 : Both nonobese clozapine - and olanzapine - treated groups displayed significant insulin resistance and impairment of glucose effectiveness compared with risperidone - treated subjects .
### Output Text:
CONCLUSIONS : Both nonobese <span class="chemical">clozapine</span> - and <span class="chemical">olanzapine</span> - treated groups displayed significant insulin resistance and impairment of <span class="chemical">glucose</span> effectiveness compared with <span class="chemical">risperidone</span> - treated subjects . 