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: The results indicated that concomitant treatment with gum Arabic and GM significantly increased creatinine and urea by about 183 and 239 % , respectively ( compared to 432 and 346 % , respectively , in rats treated with cellulose and GM ) , and decreased that of cortical GSH by 21 % ( compared to 27 % in the cellulose plus GM group ) The GM - induced proximal tubular necrosis appeared to be slightly less severe in rats given GM together with gum Arabic than in those given GM and cellulose .
### Output Text:
The results indicated that concomitant treatment with <span class="chemical">gum Arabic</span> and <span class="chemical">GM</span> significantly increased <span class="chemical">creatinine</span> and <span class="chemical">urea</span> by about 183 and 239 % , respectively ( compared to 432 and 346 % , respectively , in rats treated with cellulose and <span class="chemical">GM</span> ) , and decreased that of cortical <span class="chemical">GSH</span> by 21 % ( compared to 27 % in the cellulose plus <span class="chemical">GM</span> group ) The <span class="chemical">GM</span> - induced proximal tubular necrosis appeared to be slightly less severe in rats given <span class="chemical">GM</span> together with <span class="chemical">gum Arabic</span> than in those given <span class="chemical">GM</span> and cellulose . 