<?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 href="http://www.diyanet.gov.tr/turkish/dy/', $linkSon[0]);