var popupje;

function popup_youtube(url) {
if(popupje) {popupje.close();}
naam="popup"; links=0; boven=0; scrollen="auto";
url = "http://www.mfysiotherapie.nl/inc/popup_youtube.php?url="+url;
instellingen = 'toolbar=no,location=no,directories=no,status=no,menubar=no,scrollbars='+scrollen+',resizable=no,width=425,height=350,left='+links+',top='+boven;
popupje=window.open(url, naam, instellingen); 
}