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??????????JS???

<script language="javascript">
  function changeImg(obImg,sNewURL)
  {
       if(sNewURL!="") obImg.src=sNewURL;
  }
  </script>

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<img style="cursor:hand;" src="????" border="0" width="50" height="30" onmouseover="changeImg(this,'????');" onmouseout="changeImg(this,'????');">

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