/*var obj = document.getElementById('adtop');
obj.style.overflow = "hidden";
obj.style.textAlign = "center";
obj.innerHTML = '<a href="http://bbs.cdqss.com/thread-30407-1-1.html" target="_blank"><img src="http://cc4.cache.cdqss.com/attachments/index/200909/1253848765.3.jpg" border="0" width="960"/></a>';

var intervalId = null;
var distance = Math.ceil(obj.offsetHeight/30);

function slideUp(){
	var height = obj.offsetHeight;
	var nextHeight = height -  distance;
	
	if(obj && nextHeight > 0){
		obj.style.height = nextHeight + "px"; //把图片高度分为50个等份
	}else{
		clearInterval(intervalId);
		obj.style.display="none";
	}
}

setTimeout("setInterval(slideUp , 80)" , 5000);*/