function start() {
        imgtog(0);
        imgtog(1);
        imgtog(2);
        imgtog(3);
        imgtog(4);
        imgtog(5);
}
function imgtog(index) {
    var selected = document.getElementById("chk" + index).checked;
    if (document.getElementById("ctl00_ContentPlaceHolder1_cell" + index)) {
        document.getElementById("ctl00_ContentPlaceHolder1_cell" + index).style.display = selected ? '' : 'none';
    }
}