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: Cocaine induced no significant change in heart rate , LV dP / dt ( positive or negative ) , or LV end - diastolic volume , but it caused an increase in systolic and mean arterial pressures , LV end - diastolic pressure , and LV end - systolic volume , as well as a decrease in LV ejection fraction .
### Output Text:
<span class="chemical">Cocaine</span> induced no significant change in heart rate , LV dP / dt ( positive or negative ) , or LV end - diastolic volume , but it caused an increase in systolic and mean arterial pressures , LV end - diastolic pressure , and LV end - systolic volume , as well as a decrease in LV ejection fraction . 