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: MAIN OUTCOME MEASURES : Fasting plasma glucose and fasting serum insulin levels , insulin sensitivity index , homeostasis model assessment of insulin resistance , and glucose effectiveness .
### Output Text:
MAIN OUTCOME MEASURES : Fasting plasma <span class="chemical">glucose</span> and fasting serum insulin levels , insulin sensitivity index , homeostasis model assessment of insulin resistance , and <span class="chemical">glucose</span> effectiveness . 