help preg_replace (syntax between two word not match then replace or url syntax not match

[cflash]

$string = '<a href="https://www.uptime.com/v/_JM?version=3" />PLAY</a></div>
<a href="https://newtime.uptime.com/v/_JM?version=3" />LINK@</a></div>
<div class="class"><a href="https://www.firstdot.com/dsljdlkj@4sjdkjcnc/jdhdd.html" />LINKUP</a></div>
<a href="https://subdomain.uptime.com/v/_@%ljdmmcc=3" />subd</a></div>
<a href="https://www.cng.com/v/_JM?dkkkk#3" />GETUp</a></div>
'; 

remove Link except *.uptime.com*
HOw Can Get Result From String (OUTPUT)

<a href="https://www.uptime.com/v/_JM?version=3" />PLAY</a></div>
<a href="https://newtime.uptime.com/v/_JM?version=3" />LINK@</a></div>
<div class="class"></div>
<a href="https://subdomain.uptime.com/v/_@%ljdmmcc=3" />subd</a></div>
</div>

[something else]

$string = explode("</div>",$string);
$output = '';
foreach ($string as &$v) 
{
    if(strpos ($v, 'uptime.com'))
    {
        $output += $v;
    }
}

echo $output; 

[arnage]

Im not getting what did he wanted.