In the sentence extracted from biomedical literature, identify all the disease entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="disease"> to denote a disease.

### Input Text: With respect to their roles in apoptosis , loss of atm rendered thymocytes only partly resistant to irradiation - induced apoptosis , whereas additional loss of p53 engendered complete resistance .
### Output Text:
With respect to their roles in apoptosis , loss of atm rendered thymocytes only partly resistant to irradiation - induced apoptosis , whereas additional loss of p53 engendered complete resistance . 