Passing Querystring within the same page

Hi all,
Can we pass querystring in the same page?? if yes then how ?
i am using Tab Container control of AJAX Toolkit and in that i have 5 tabs all of them gets the value through querystring from another page but i want to pass different querystring to tab no 4 so for that i am trying to pass another querystring on the same page on TabContainer1_ActiveTabChanged event.
please tell me how do i give another querystring to tab no 4
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