function menu_goto( isod ) {
	qString = "";
	if( document.search.q.value.length != 0 ) {
		qString = "?q=" + document.search.q.value;
	} 

    selecteditem = isod.selectedIndex;
    isodValue = isod.options[ selecteditem ].value ;


    if(isodValue.length != 0) {
	switch( isodValue ) {
		case "0":
			location.href = "http://www.vitrax.com/products/catalog_index.html" + qString;
			break;
		case "1":
			location.href = "http://www.vitrax.com/products/3H/chemical_index.html" + qString;
			break;
		case "2":
			location.href = "http://www.vitrax.com/products/14C/chemical_index.html" + qString;
			break;
		case "3":
			location.href = "http://www.vitrax.com/products/125I/chemical_index.html" + qString;
			break;
	}
    }
}