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.
One example: 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 is here: 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.

Now, solve this: Abstract: Serum IAP and ferritin values were measured preoperatively in 83 resectable gastric cancer patients. IAP was significantly higher in them than in normal subjects, and increased gradually with progression of cancer, and the values at stages III and IV were significantly higher than that at stage I. It was significantly higher in the cases of n(+) than in those of n(-), and in the cases of noncurative resection than in those of curative resection. Ferritin was significantly higher in them than in normal subjects and mammary cancer patients, and in males than in females, and the values at stages I and IV were significantly higher than that at stage III. OK-432 was serially administered pre- and postoperatively in 83 cases and only postoperatively in 33 cases. IAP increased markedly at 1 week postoperatively and was reduced gradually at 2 and 4 weeks. Ferritin increased markedly at 1 week after operation and reached the maximum value at 2 weeks and was reduced toward the value of 1 week at 4 weeks. However, these changes showed no significant difference between the both groups.
Solution:
Breast Neoplasms