Javascript 正则保留汉字

<script type="text/javascript"> 
var str="被窝放屁，能闻能捂1Id=?666。，吃《葡萄》不吐：&nbsp<#!#$%^&*()葡萄籽"; 
alert(str.replace(/[^u4e00-u9fa5]/gi,"")); 
</script>