21.  But in rare cases a virulent strain of N. meningitidis manages to penetrate mucosal cells in our respiratory tract.

22.  But Livian said the accident was a rare case of failure among thousands of sheds.

23.  But only in rare cases do designers or apparel companies take their complaints to court.

24.  But it said that the shooting of Diallo is that rare case.

25.  But the federal government, seeking to discourage such tests, has only in rare cases accepted the results of human tests when setting regulations.

26.  But some patients developed heart problems, including rare cases of congestive heart failure, studies show.

27.  But this is a rare case.

28.  But this may be a rare case where the cleansing is more than skin deep.

29.  But this was a rare case.

30.  But when judges misbehave, except in rare cases, we no longer are allowed to know about it.