<script type="text/javascript">
function recp() {
  setInterval(function()
{
    $("#my").load(location.href+ ' #my');
});
}
</script>


<div id="my"><?php echo date('a:i:s'); ?></div>

<div id="my"><div id="my">pm:25:40</div></div>

<div id="my"><?php echo date('a:i:s'); ?></div>

<script type="text/javascript">
function recp() {
  setInterval(function()
  {
    $("#result").load(location.href+ ' #my');
  });
}
</script>

<div id="result">
  <div id="my"><?php echo date('a:i:s'); ?></div>
</div>

<script type="text/javascript">
function recp() {
  setInterval(function() {
      $.get(location.href, function(data){
          $('#my').empty().append( $(data).find('#my').children() );
      });
  });
}
</script>

<script type="text/javascript">
function recp() {
  setInterval(function()
    {
        $("<div/>").load(location.href+ ' #my', function(response, status, xhr) {
            $("#my").replaceWith(response);
            $(this).remove();
        });
    });
}
</script>