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: Under such conditions , angiotensin II receptor blockade by losartan probably induced a critical fall in glomerular filtration pressure .
### Output Text:
Under such conditions , <span class="chemical">angiotensin II</span> receptor blockade by <span class="chemical">losartan</span> probably induced a critical fall in glomerular filtration pressure . 