document.onkeydown = NavigateThrough;

function NavigateThrough (event)
{
        if (!document.getElementById) return;

        if (window.event) event = window.event;

        if (event.ctrlKey)
        {
                var link = null;
                var href = null;
                switch (event.keyCode ? event.keyCode : event.which ? event.which : null)
                {
                        case 0x25:
                                link = document.getElementById ('NextLink');
                                break;
                        case 0x27:
                                link = document.getElementById ('PrevLink');
                                break;
                }

                if (link && link.href) document.location = link.href;
                if (href) document.location = href;
        }                       
}