function show_list(){
  document.getElementById("slist").style.visibility="visible";
}
function hide_list(){
  document.getElementById("slist").style.visibility="hidden";
}
function changesearch(i) {
  var url = './keresok.php';
  var q = document.getElementById("gt").value;
  var params = 'a='+i+'&q='+q;
  var myAjax = new Ajax.Updater( 'form', url, { method: 'get', parameters: params });
}