If your result has all the html from your aspx file and an element with id "DupPpl" exists in that html you can get the element using jquery contents:
try:
var oldDiv = $('#DupPpl');
var newDiv = $(result).contents().find('#DupPpl').html();
oldDiv.replaceWith(newDiv);
Use the same code to get other elements:
$(result).contents().find('YOUR_ELEMENT_ID').html();