function ImprimeFicha(id) 
{
	xdist = parseInt((screen.width - 750) /2);
	ydist = parseInt((screen.height - 400) /2);
	ventana=window.open("../includes/imprimir_ficha.php?id="+id,"ventana","width=750,height=400,scrollbars=yes,left ="+xdist+",top="+ydist);
}