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.
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Question: Abstract: From a large series of patients referred for endoscopic retrograde cholangiopancreatography to one endoscopist, 49 patients had the duodenoscopic appearance of a periampullary tumour. Thirty eight of these lesions were neoplastic, but the remaining 11 patients had inflammatory non-neoplastic lesions (pseudotumours). These could not be distinguished from the neoplasms on endoscopic appearances. The cholangiopancreatograms were similar except that the diameter of the pancreatic duct tended to be higher in the tumour group and gall stones were present significantly more often in the patients with pseudotumour. Endoscopic biopsy correctly diagnosed 28 of 34 ampullary carcinomas. Two of the 11 pseudotumour patients were subjected to surgical excision biopsy because of suspicious histological features of endoscopic biopsy. In the neoplastic group 19 patients underwent Whipple's procedure, seven surgical bypass, seven endoscopic sphincterotomy only and five died without successful biliary drainage. The overall one year survival was 44.7%. By contrast, the patients with pseudotumours were clinically well at a median follow up 24 months (range 12-41 months), after endoscopic sphincterotomy except for one 89 year old patient who died 22 months later from unrelated causes.

Answer: Adult

Question: Abstract: By use of an improved density measuring system, we found that the gravimetric density of arterial blood of dogs fluctuates at the same frequency as the spontaneous or mechanical ventilation. Similar density fluctuations were observed in the blood leaving isolated, perfused lobes of dogs that were ventilated cyclicly. Employing an analysis that balanced the erythrocyte and plasma flows through distensible capillaries containing blood with a tube hematocrit lower than the hematocrit in large blood vessels, we derived a relationship to estimate from the density fluctuation the change in pulmonary capillary blood volume (Vc). For mechanical ventilation, the maximum change in density over one ventilation cycle increased from 0.084 +/- 0.01 to 0.47 +/- 0.05 (SE) g/l as the frequency decreased from 29 to 6 cycles/min. These density changes were estimated to be the result of an 1-16% change in Vc. A larger tidal volume for the mechanical ventilation led to a larger density fluctuation. The maximum density change of spontaneous respiration of 6 cycles/min was one-sixth of the mechanical case, indicating a much smaller change in Vc during spontaneous respiration. When the airway flow resistance was increased for spontaneous respiration, larger density fluctuations were observed.

Answer: Airway Resistance

Question: Abstract: Distribution and elimination of cefamandole 2 g iv were studied in 11 morbidly obese patients during a gastric bypass operation and again on the first postoperative day. Serum, subcutaneous adipose tissue, wound drainage, and urine were analyzed by high performance liquid chromatography for cefamandole and pharmacokinetic parameters from the intraoperative period were compared to those obtained postoperatively. Total body clearance was significantly greater (p less than 0.001) postoperatively (297 ml/min) than intraoperatively (254 ml/min). Volume changes were unpredictable but the elimination rate constant tended to increase postoperatively. Renal clearance and percentage of urinary recovery were significantly increased (p less than 0.01) postoperatively. The patients had a mean (+/- SD) volume of the central compartment of 10.3 (+/- 2.3) L, volume at steady state of 18.3 (+/- 3.9) L, and elimination rate constant of 1.67 (+/- 0.63) h-1. Tissue concentrations of cefamandole were highest during the first hour after drug administration and were less than 1 microgram/g after 3.5 hours. Mean wound drainage concentrations ranged between 10 and 12 micrograms/ml during a dosing interval and dropped to 7 micrograms/ml 12 hours after the last dose. Intraoperative dosing of cefamandole is required to maintain subcutaneous adipose tissue concentrations greater than 1 microgram/g during procedures longer than three hours in morbidly obese patients. A postoperative dose of cefamandole 2 g iv q6h will provide sustained and therapeutic concentrations in the wound drainage of morbidly obese patients.

Answer:
Adipose Tissue