Turn out old chinese case holding medical protection (6)

I believe the answer is:

happen

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'turn out' is the definition.
(I've seen this before)

I don't understand the remainder of the clue.

(Other definitions for happen that I've seen before include "perhaps for Yorkshire" , "Take place" , "maybe, in the Yorkshire Dales" , "Occur" , "Chance" .)

I've seen this clue in The Irish Times.

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