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</div></div></li></ul><ul class="issue-month-detail single-issue"><li ><div class="highwire-article-citation highwire-citation-type-highwire-issue node135524" data-node-nid="135524" id="node-135524--2283759875" data-pisa="thoraxjnl;28/5" data-pisa-master="thoraxjnl;28/5" data-apath="/thoraxjnl/28/5.atom"><div class="highwire-cite highwire-cite-highwire-issue highwire-citation-bmjj-archive-citation clearfix issue-link" class="issue-link" data-cover-image="https://thorax.bmj.com/sites/default/files/styles/medium/public/highwire/thoraxjnl/28/5.cover.gif?itok=YKW18tcp" data-cover-issue-url="/content/28/5"> <div><a href="/content/28/5" class="" data-icon-position="" data-hide-link-title="0">Vol 28, Issue 5</a></div> </div></div></li></ul><ul class="issue-month-detail single-issue"><li ><div class="highwire-article-citation highwire-citation-type-highwire-issue node135520" data-node-nid="135520" id="node-135520--21733273932" data-pisa="thoraxjnl;28/4" data-pisa-master="thoraxjnl;28/4" 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