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: Eighty - nine new referral hypertensive out - patients and 46 new referral non - hypertensive chronically physically ill out - patients completed a mood rating scale at regular intervals for one year .
### Output Text:
Eighty - nine new referral hypertensive out - patients and 46 new referral non - hypertensive chronically physically ill out - patients completed a mood rating scale at regular intervals for one year . 