function showhide(el, str_oculto, str_normal) {
    var parent = el.parentNode;
    var childs = parent.childNodes;
    
    for (var i = 0; i < childs.length; i++) {
        var child = childs[i];
        
        if (child.tagName == 'DIV' && child.className == 'ocutavel') {
            if (child.style.display == 'block') {
                child.style.display = 'none';
                
                if (str_normal != null) {
                    el.innerHTML = str_oculto;
                }
            } else {
                child.style.display = 'block';
                
                if (str_normal != null) {
                    el.innerHTML = str_normal;
                }
            }
        }
    }
}