Crm 2011 hiding Sales. Markerting, Common Nav Group in Entity left nav

This javascript hides the Sales Nav Group under Related left nav on CRM 2011 Entity

//Hides Nav Group inside a crm 2011 enitity

function hideNavGroup(navigationName) {
    var navItems = document.getElementById("crmFormNavSubareas");
    for (i = 0; i < navItems.childNodes.length; i++) {
        var navItem = navItems.childNodes.item(i);
       var itemName = navItem.firstChild.lastChild.innerText;
        if (itemName == navigationName ) {
   navItem.style.display = "none"
        }
    }
}

Consumption:

hideNavGroup("Sales");

The Sales group is removed,

You Can hide Service by:

hideNavGroup("Services");