Trouble with my Theme

Im having some trouble with my theme, i have installed and fixed many bugs, but have one and i not finding the solution, my blog is http://blogdopatu.ueuo.com/ and on index page, the posts are organized on category-based headlines, i used this function

function noticias(){
{
global $post;
$myposts = get_posts('category=1');
echo '<ul>' . "\n";
foreach($myposts as $post) {
echo '<ul class="post-data">';
echo '<span id="lananoticia"><a href="' . get_permalink() . '">' . get_the_title() . '</a></span>' . "\n";
echo '</ul>';
}
echo '</ul>' . "\n";
echo '</li>' . "\n";
}
};

but this is limited for 5 posts, and i want to limit to 10-15, what i need to do?