Jquery Newly inserted table rows disappear after 2 seconds

the newly inserted rows just showed for 2 secs.then disappeared...

$item = $( "<tr><td><input type=\"text\" class=\"inputBig\" /></td>"+ 
               "<td><input type=\"checkbox\" c开发者_运维技巧hecked=\"checked\" /></td></tr>");

$item.prependTo($("#tbodyPI")).show();

This code alone will not cause the row to disappear.

You have some other code which is removing it.