function getXMLHTTPRequest() {
   var req =  false;
   try {
      /* for Firefox */
      req = new XMLHttpRequest(); 
   } catch (err) {
      try {
         /* for some versions of IE */
         req = new ActiveXObject("Msxml2.XMLHTTP");
      } catch (err) {
         try {
            /* for some other versions of IE */
            req = new ActiveXObject("Microsoft.XMLHTTP");
         } catch (err) {
            req = false;
         }
     }
   }
   
   return req;
}

function getPage(nr) 
{
  var thePage = "presscontent.php?pno="+nr";
  alert(thePage);
  myReq.open("GET", thePage, true);
  myReq.onreadystatechange = theHTTPResponse;
  myReq.send(null);
}

function theHTTPResponse() {
  if (myReq.readyState == 4) {
    if(myReq.status == 200) {
       var ps = myReq.responseXML.getElementsByTagName("ps")[0];
       document.getElementById('presshow').innerHTML = tps.childNodes[0].nodeValue;
    }
  } else {
    document.getElementById('presshow').innerHTML = '<img src="ajax-loader.gif"/>';
  }
}