<option value="/journal.php?journalid=4451389" selected>текст 1</option> <option value="/journal.php?journalid=2142878" >текст 2</option> <option value="/journal.php?journalid=2298390" >текст 3</option> <option value="/journal.php?journalid=3224740" >текст 4</option>
<input type="checkbox" name="4451389" checked="checked" />текст 1<br /><input type="checkbox" name="2142878" checked="checked" />текст 2<br /><input type="checkbox" name="2298390" checked="checked" />текст 3<br /><input type="checkbox" name="3224740" checked="checked" />текст 4<br />
$patt = '#<option.*?journalid=(\d+).*?>(.*?)</option>#';$repl = '<input type="checkbox" name="$1" checked="checked" />$2<br />';$res = preg_replace($patt, $repl, $text);