function AbreJanela(url,w,h,sb,rs){
  if (!w||!h) {sb='no'};
  if (!w) {w=581}; 
  if (!h) {h=400};
  if (!sb) {sb='no'};
  if (!rs) {rs='no'};
  newWindow = window.open(url,'','width='+w+',height='+h+',top='+(screen.height-h)/2+',left='+(screen.width-w)/2+',toolbar=no,location=0,directories=0,statusbar=no,menuBar=no,scrollBars='+sb+',resizable='+rs);
  newWindow.location.href = url;
  if (newWindow.opener == null) newWindow.opener = self;
  newWindow.focus();
}