In 1947, McFarlane and Pilling reported a fibrinolytic activity in human urine that was later named urokinase. Urokinase activates plasminogen, helping to break down fibrin clots. It became part of the broader development of thrombolytic medicine for clot-related disease.

The discovery of urokinase in 1947 expanded the metaphorical landscape for poets, allowing them to explore themes of unblocking and restoration. This scientific advancement resonated in poetry that reflected on emotional flow and the complexities of human experience.