网站上面有这种切换效果
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<p>群居动物的这种行为颠覆了我们通常认为的，在动物世界通行的“丛林法则”，动物不都自私，不都是弱肉强食的。<imgsrc="/newimg/i2.gif"alt="详细"width="3"height="5"/><ahref="http://tech.163.com/discover/"class="cDRed">详细</a></p>
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<divclass="pic"><ahref="http://tech.163.com/special/00091MNJ/itobserve015.html"><imgsrc="http://cimg.163.com/tech/2006/1/17/2006011711483290a60.jpg"alt="WAPI并非贸易阴谋"width="240"height="180"border="0"/></a></div>
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<divclass="text">>更多头图新闻</div>
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<ul>
<li>1</li>
<li><ahref="javascript:setFocus1(2);"target="_self">2</a></li>
<li><ahref="javascript:setFocus1(3);"target="_self">3</a></li>
<li><ahref="javascript:setFocus1(4);"target="_self">4</a></li>
</ul>
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<ul>
<li><ahref="javascript:setFocus1(1);"target="_self">1</a></li>
<li>2</li>
<li><ahref="javascript:setFocus1(3);"target="_self">3</a></li>
<li><ahref="javascript:setFocus1(4);"target="_self">4</a></li>
</ul>
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<ul>
<li><ahref="javascript:setFocus1(1);"target="_self">1</a></li>
<li><ahref="javascript:setFocus1(2);"target="_self">2</a></li>
<li>3</li>
<li><ahref="javascript:setFocus1(4);"target="_self">4</a></li>
</ul>
</div>
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<ul>
<li><ahref="javascript:setFocus1(1);"target="_self">1</a></li>
<li><ahref="javascript:setFocus1(2);"target="_self">2</a></li>
<li><ahref="javascript:setFocus1(3);"target="_self">3</a></li>
<li>4</li>
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