function mostrar(img,winName,ruta){
	var ancho= screen.availWidth;
	var alto= screen.availHeight;
	var izq= (ancho-530)/2;
	var arr= (alto-397)/2;
	var img = ruta+img;
	window.open("foto.php?img="+img,winName,"width=530,height=397,left="+izq+",top="+arr);
}