function change_big_pic (big_img_name, pic_url) {
			temp = new Image();
			temp.src = pic_url;
			document.getElementById (big_img_name).src = temp.src;
		}

		function highlight (a_num) {
			for (i=1; true; i++) {
				if (document.getElementById ('pr_'+i)) {
					document.getElementById ('pr_'+i).className = '';
				}
				else {
					break;
				}
			}
			if (document.getElementById ('pr_'+a_num)) {
				document.getElementById ('pr_'+a_num).className = 'active';
			}
		}
		
		function show_texttab (a_num) {
			for (i=1; true; i++) {
				if (document.getElementById ('tx_'+i)) {
					document.getElementById ('tx_'+i).style.display = 'none';
				}
				else {
					break;
				}
			}
			if (document.getElementById ('tx_'+a_num)) {
					document.getElementById ('tx_'+a_num).style.display = 'block';
			}
		}