<!DOCTYPE HTML>
<html>
<head>
<title></title>
<style type="text/css">
.activ{
background-color: #00FFFF;
}
</style>
</head>
<body>
<div class="content" ><b>bbbbb</b>
</div>
<div class="content" >test
</div>
<div class="content" ><b>bbbbb</b>
</div>
<div class="content" >test
</div>
<div class="content" ><b>bbbbb</b>
</div>
<div class="content" >test
</div>
<script src="http://code.jquery.com/jquery-latest.js"></script>
<script language="JavaScript" type="text/javascript">
$(".content:not(:has(b))").addClass("activ");
</script>
</body>
</html>