https://dzl.de/publication/10-1183-23120541-00190-2023/
Assessment of efficacy and safety of endoscopic lung volume reduction with one-way valves in...
INTRODUCTION: Endoscopic lung volume reduction (ELVR) with one-way valves produces beneficial outcomes in patients with severe emphysema. Evidence on the...
one way valvesassessmentefficacysafetyendoscopic
https://hydrospares.co.uk/plumbing/valves/check-one-way-valves
Check / One-Way Valves
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