function altura_iframe(){
int_alt = document.getElementById('interna').offsetHeight;
if(int_alt<290){
parent.document.getElementById('conteudo').style.height = '300px';
parent.document.getElementById('conteudo').style.overflow = 'hidden';
document.getElementById('interna').style.height = '290px';
} else {
int_alt = int_alt;
parent.document.getElementById('conteudo').style.height = ''+ int_alt +'px';
parent.document.getElementById('conteudo').style.overflow = 'hidden';
}
parent.scrollTo(0,0);
}