从Google加载Jquery以提高网站性能

<SCRIPT type=text/javascript src="http://ajax.googleapis.com/ajax/libs/jquery/1.4/jquery.min.js"></SCRIPT>

/*无法从Google加载，从本地加载*/
<script>!window.jQuery && document.write('<SCRIPT src="/js/jquery-1.4.3.min.js"><\/SCRIPT>');</script>