function check(page) {
  var content;
  var fullpath = window.location.href;
  var ind = fullpath.indexOf("?")+1;
  if (ind > 0) {
    loaddoc = fullpath.substring(ind);
    if (loaddoc) content = loaddoc;
  } else { content = page; }
  contentframe.innerHTML = '<iframe name="content" src="' + content + '" width=572 height=551 frameborder="0" scrolling="auto" allowtransparency></iframe>';
}