Is it possible to retrieve some (in this case) text with an ajax request and modify it before showing it in e.g. a div?

I've got the following code

$.ajax({url: "Files/" + par + ".php",
success: function(result){
    $("#box").html(result);
}

Where par is a parameter (for example foo). This would retrieve the file foo.php and place the obtained file contents in a div called box.

Now I wonder if you could do the following:
Suppose the content of foo.php was as followed:

Some title

some text here...

A sub title

more text....

Is it possible to place some code or a sentence between the title and the text? So the result would be like this:

Some title

This sentence was added
some text here...

A sub title

more text...

Yes, absolutely.

success: function(result){
    result = result.replace("some text here...", 
        "<i>This sentence was added</i><br />some text here...");
    $("#box").html(result);
}