function showDown(evt) {	
	evt = (evt)? evt : ((event)? event : null);	
	/*if (agt.indexOf("firefox") != -1) return 'Firefox';
	if (agt.indexOf("msie") != -1) return 'Internet Explorer';
	if (agt.indexOf("mozilla/5.0") != -1) return 'Mozilla';*/
	if (evt) {
	if(agt.indexOf("mozilla/5.0") != -1){
		 if(evt.keyCode == 8 && (evt.srcElement.type!= "text" && evt.srcElement.type!= "textarea" && evt.srcElement.type!= "password" )) {
			// When backspace is pressed but not in form element			
			cancelKey(evt);
		}else if (evt.keyCode == 116) {
		// When F5 is pressed
			//alert('f5');
			cancelKey(evt);
		}else if (evt.keyCode == 122) {	// When F11 is pressed
			cancelKey(evt);
		}else if (evt.ctrlKey && (evt.keyCode == 78 || evt.keyCode == 82)) {	// When ctrl is pressed with R or N
			cancelKey(evt);
		}else if (evt.altKey && evt.keyCode==37 ) {	// stop Alt left cursor
			return false;
		}
	  }	else if(agt.indexOf("msie") != -1 ){
		if(event.keyCode == 8 && (event.srcElement.type!= "text" && event.srcElement.type!= "textarea" && event.srcElement.type!= "password" )) {
			// When backspace is pressed but not in form element			
			cancelKey(evt);
		}else if (event.keyCode == 116) {
		// When F5 is pressed
			//alert('f5');
			cancelKey(evt);
		}else if (event.keyCode == 122) {	// When F11 is pressed
			cancelKey(evt);
		}else if (event.ctrlKey && (event.keyCode == 78 || event.keyCode == 82)) {	// When ctrl is pressed with R or N
			cancelKey(evt);
		}else if (event.altKey && event.keyCode==37 ) {	// stop Alt left cursor
			return false;
		}
	  }
	}
}
function cancelKey(evt) {
if (evt.preventDefault) {
	evt.preventDefault();
	return false;
}else {
	evt.keyCode = 0;
	evt.returnValue = false;
}
}