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The requested URL /bookmarks/mark?op=add&bkmk=https%3A//jim.bmj.com/content/67/4/761&title=The%20characteristics%20and%20clinical%20significance%20of%20mucin%20levels%20in%20bronchoalveolar%20lavage%20fluid%20of%20patients%20with%20interstitial%20lung%20disease was not found on this server. That’s all we know.