$sql = mysql_query("SELECT * FROM product ORDER BY date DESC LIMIT 20");
$i = 0;
while ($row = mysql_fetch_array($sql))
{
    if ($i < 10)
    {
        $class = "active item";
    } else
    {
        $class = "item";
    }
    echo "
<div class=\"$class\">
	<ul class=\"thumbnails\">	
            <li class=\"span3\">
		 <div class=\"product-box\">

                      Ürün1

                 </div>
            </li>
         </ul>
</div>
";
    $i++;
}