- preg_replace: documentation ( source)
<?php
$_content = 'hello <p> </p><p ></p><div><p> </p><a href="http://feeds.feedburner.com/~ff/NakedCapitalism?a=erNtBkuNSQs:shUVd8nk1SU:yIl2AUoC8zA"> <img src="http://feeds.feedburner.com/~ff/NakedCapitalism?d=yIl2AUoC8zA" alt="" border="0" /></a> <a href="http://feeds.feedburner.com/~ff/NakedCapitalism?a=erNtBkuNSQs:shUVd8nk1SU:V_sGLiPBpWU"><img src="http://feeds.feedburner.com/~ff/NakedCapitalism?i=erNtBkuNSQs:shUVd8nk1SU:V_sGLiPBpWU" alt="" border="0" /></a> <a href="http://feeds.feedburner.com/~ff/NakedCapitalism?a=erNtBkuNSQs:shUVd8nk1SU:l6gmwiTKsz0"><img src="http://feeds.feedburner.com/~ff/NakedCapitalism?d=l6gmwiTKsz0" alt="" border="0" /></a> <a href="http://feeds.feedburner.com/~ff/NakedCapitalism?a=erNtBkuNSQs:shUVd8nk1SU:F7zBnMyn0Lo"><img src="http://feeds.feedburner.com/~ff/NakedCapitalism?i=erNtBkuNSQs:shUVd8nk1SU:F7zBnMyn0Lo" alt="" border="0" /></a> <a href="http://feeds.feedburner.com/~ff/NakedCapitalism?a=erNtBkuNSQs:shUVd8nk1SU:cGdyc7Q-1BI"><img src="http://feeds.feedburner.com/~ff/NakedCapitalism?d=cGdyc7Q-1BI" alt="" border="0" /></a> <a href="http://feeds.feedburner.com/~ff/NakedCapitalism?a=erNtBkuNSQs:shUVd8nk1SU:gIN9vFwOqvQ"><img src="http://feeds.feedburner.com/~ff/NakedCapitalism?i=erNtBkuNSQs:shUVd8nk1SU:gIN9vFwOqvQ" alt="" border="0" /></a> <a href="http://feeds.feedburner.com/~ff/NakedCapitalism?a=erNtBkuNSQs:shUVd8nk1SU:qj6IDK7rITs"> <img src="http://feeds.feedburner.com/~ff/NakedCapitalism?d=qj6IDK7rITs" alt="" border="0" /></a></div>there';
$_content = preg_replace('#<img([^>]*?)(\/feeds.feedburner.com\/~ff\/)[^>]*>#i', '', $_content);
$_content = preg_replace('#<a [^>]*>(\s*)<\/a>#i', '',$_content);
$_content = preg_replace('#<p[^>]*>(\s*)</p>#i', '', $_content);
$_content = preg_replace('#<div[^>]*>(\s*)<\/div>#i', '', $_content);
echo $_content;