function loadPage(page)
{
    var strText = "";

    var oTDTab1 = document.getElementById("tdTab1");
    var oSPBoton1 = document.getElementById("spBoton1");
    var oTDTab2 = document.getElementById("tdTab2");
    var oSPBoton2 = document.getElementById("spBoton2");
    var oIframe = document.getElementById("ifPaginas");

    var strClass1 = "";

    var strClass2 = "";
    var strSpanHtml2 = "";

    var strSource = "pagina.php?pag=";
    var pagina1 = "";
    var pagina2 = "";
    
    switch(page)
    {
        case "red":
            strText = "Red NSI";
            break;
        case "unete":
            strText = "Unete a la Red";
            break;
        case "miembros":
            strText = "Miembros";
            break;
        case "publicaciones":
            strText = "Publicaciones";
            break;
        case "eventos":
            strText = "Eventos";
            break;
    }

    oIframe.setAttribute("src", strSource + page);

    oTDTab1.attributes["class"].value = strClass1;
    oSPBoton1.innerHTML = strText;

    oTDTab2.attributes["class"].value = strClass2;
    oSPBoton2.innerHTML = strSpanHtml2;
}