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: A significant relationship was observed between maximal cTnT and the extent of myocardial morphological changes , and between LV diameters / BW and histological findings .
### Output Text:
A significant relationship was observed between maximal cTnT and the extent of myocardial morphological changes , and between LV diameters / BW and histological findings . 