<table width=160 border="0" cellpadding="0" cellspacing="0" >
<tr>
	<td colspan=3 height=24 bgcolor="#ffffff"><table border="0" cellpadding="0" cellspacing="0">
		<tr>
			<td height=24 background="bg_1.gif" id="bt0" onmouseover="javascript:showPage(0);javascript:checkbr0(0);" STYLE='cursor:hand' width=80 align=center>网络</td>
			<td background="bg_2.gif" STYLE='cursor:hand' id="bt1" onmouseover="javascript:showPage(1);javascript:checkbr0(1);" width=80 align=center>信息</td>
			<td background="bg_2.gif" STYLE='cursor:hand' id="bt2" onmouseover="javascript:showPage(2);javascript:checkbr0(2);" width=80 align=center>编程</td>
			<td background="bg_2.gif" STYLE='cursor:hand' id="bt3" onmouseover="javascript:showPage(3);javascript:checkbr0(3);" width=80 align=center>通信</td>
		</tr>
	</table></td>
</tr>

<tr>
	<td width=1 bgcolor="#6BA2DE"></td>
	<td height=1 bgcolor="#AEB8C3"></td>
	<td width=1 bgcolor="#6BA2DE"></td>
</tr>
<tr>
	<td><div id="b2bContent"></div></td>
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<script language="javascript">
<!--
	b2bStr = new Array(); 
	b2bStr[0]= "<br>网络相关信息";
	b2bStr[1]= "<br>信息时代相关主题";
	b2bStr[2]= "<br>javascript脚本语言";
	b2bStr[3]= "<br>通讯技术广泛应用";
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	showPage(0)
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