jsの日付とミリ秒数は互いに変換されます.

<script type="text/javascript">

     var startTime = '2014-04-11 18:22:55';

     var endTime = startTime.replace(new RegExp("-","gm"),"/");

	 alert(endTime);

     var oldTime = (new Date(endTime )).getTime(); //       

	 alert(oldTime);

     var newTime = new Date(oldTime); //    


</script>