Detailed Instructions: Given an abstract, generate a keyword (a noun phrase) that best describes the focus or contribution of the paper. Such keywords can be directly from the given abstract or outside it.
See one example below:
Problem: Abstract: Some patients converted from ventricular fibrillation to organized rhythms by defibrillation - trained ambulance technicians(EMT - Ds) will refibrillate before hospital arrival.The authors analyzed 271 cases of ventricular fibrillation managed by EMT - Ds working without paramedic back - up.Of 111 patients initially converted to organized rhythms, 19(17 % ) refibrillated, 11(58 % ) of whom were reconverted to perfusing rhythms, including nine of 11(82 % ) who had spontaneous pulses prior to refibrillation.Among patients initially converted to organized rhythms, hospital admission rates were lower for patients who refibrillated than for patients who did not(53 % versus 76 % , P = NS), although discharge rates were virtually identical(37 % and 35 % , respectively).Scene - to - hospital transport times were not predictively associated with either the frequency of refibrillation or patient outcome.Defibrillation - trained EMTs can effectively manage refibrillation with additional shocks and are not at a significant disadvantage when paramedic back - up is not available.
Solution: Ventricular Fibrillation
Explanation: This term is directly present in the abstract and it is one of the main topic in it. So can be chosen as the medical subject heading.

Problem: Abstract: The Inyo nail is a new intramedullary device for the treatment of fractures of the distal fibula. It is a tapered V-shaped nail made of malleable stainless steel, which provides rigid fracture fixation. Torsional stress is resisted because of its triflanged shape. It may be introduced closed, using the image intensifier. Two groups of patients were evaluated: Group I was treated with the Inyo nail and Group II was treated by the Association For the Study of Internal Fixation (ASIF) technique. Eighty-five percent of the patients in Group I were rated as good, compared with 63% in Group II. There was significantly less morbidity and complications in Group I. Several factors must be observed in the treatment of ankle fractures. Stress radiographs must be obtained intraoperative. Surgery may be indicated in unstable supination lateral rotation Type II injuries, if these occur in patients with high physical demands. Anatomic reduction of the lateral malleolus must be obtained. Early weight-bearing and motion produces the best result. Late reconstruction of malunions can be accomplished using the Inyo nail.
Solution:
Adult