app.get('/mypartial',function (req,res) {
    //compute data here
    res.render('mypartial',{layout: false,data: data});
});

然后使用jQuery .get或.ajax调用将新HTML加载到/ mypartial.

然后使用jQuery替换父元素的HTML

$('#idofparentelementofyourpartial').html(responseHTML);

另见my answer to this similar question.