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: The patient was fully conscious , blood pressure 120 / 80 mmHg , pulse rate 100 x / minute , regular .
### Output Text:
The patient was fully conscious , blood pressure 120 / 80 mmHg , pulse rate 100 x / minute , regular . 