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: Multidisciplinary approaches with long - term psychiatric follow - up may contribute to low post - transplant suicide rates seen and low rates of graft loss because of non - compliance .
### Output Text:
Multidisciplinary approaches with long - term psychiatric follow - up may contribute to low post - transplant suicide rates seen and low rates of graft loss because of non - compliance . 