404. That’s an error.

The requested URL /bookmarks/mark?op=add&bkmk=http%3A//pharmrev.aspetjournals.org/content/early/2010/04/27/pr.109.002436&title=Beyond%20Desensitization%3A%20Physiological%20Relevance%20of%20Arrestin-Dependent%20Signaling was not found on this server. That’s all we know.