You are looking at the HTML representation of the XML format.
HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query-continue>
    <alltransclusions gatcontinue="Stop|790" />
  </query-continue>
  <query>
    <pages>
      <page pageid="21" ns="0" title="7-кето дегидроэпиандростерон" />
      <page pageid="27" ns="0" title="11-OXO" />
      <page pageid="63" ns="0" title="Анаболические стероиды" />
      <page pageid="488" ns="0" title="Инсулин" />
      <page pageid="725" ns="0" title="Многоповторные приседания" />
      <page pageid="775" ns="0" title="Андроген" />
      <page pageid="779" ns="0" title="Кофеин" />
      <page pageid="1664" ns="0" title="Метоксиизофлавон" />
      <page pageid="1881" ns="0" title="11-кетотестостерон" />
      <page pageid="2030" ns="0" title="NO-Xplode от BSN" />
    </pages>
  </query>
</api>