var pass = 335;

// var content = 'NEW';
var content = '<img src="http://www.ohshimaganka.com/sozai/new.gif" alt="�Å�V�î•ñ" />';

var currentDate = new Date();
var spans = document.getElementsByTagName('span');

for (i = 0; i < spans.length; i++) {
if(spans[i].getAttribute('class') == 'new' ||
spans[i].getAttribute('className') == 'new') {
time = spans[i].innerHTML.split(":");
var entryDate = new Date(time[0], time[1]-1, time[2], time[3], time[4], time[5]);
var now = (entryDate.getTime() - currentDate.getTime())/(60*60*1000);
now = Math.ceil(now);
if(-now <= pass){
spans[i].innerHTML = content;
spans[i].style.display = 'inline';
}
}
}