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: One month of oral galactose treatment initiated immediately after the STZ - icv administration , successfully prevented development of the STZ - icv - induced cognitive deficits .
### Output Text:
One month of oral <span class="chemical">galactose</span> treatment initiated immediately after the <span class="chemical">STZ</span> - icv administration , successfully prevented development of the <span class="chemical">STZ</span> - icv - induced cognitive deficits . 