<?php 
$site= file_get_contents("http://www.diyanet.gov.tr/turkish/dy/default.aspx"); 
$link = explode('<div id="duyurular" >',$site); 
$linkSon = explode('</div>',$link[1]); 

echo preg_replace('@<a(.*?)href="@i', '<a$1href="http://www.diyanet.gov.tr/turkish/dy/', $linkSon[0]);