function changeBbs(prm){
	document.images["img_right01"].src = "images/right01_up.jpg";
	document.images["img_right02"].src = "images/right02_up.jpg";
	document.images["img_right03"].src = "images/right03_up.jpg";
	document.images["img_right04"].src = "images/right04_up.jpg";

	
	
	imgTarget = "img_" + prm;
	document.images[imgTarget].src = "images/" + prm + "_down.jpg";
	
	document.getElementById("show_right01").style.display = "none";
	document.getElementById("show_right02").style.display = "none";
	document.getElementById("show_right03").style.display = "none";
	document.getElementById("show_right04").style.display = "none";
	

	
	
	var dispTarget = "show_" + prm;
	document.getElementById(dispTarget).style.display = "block";

		
	
}