In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
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Question: Context: Surgery has been the gold standard in the treatment of adult pyloric stenosis (APS). The introduction of proton pump inhibitors (PPIs) in 1989 revolutionised the treatment of peptic ulcer disease and its complications.', 'We carried out a prospective study to evaluate the effectiveness of PPIs as an alternative to surgery for treatment of APS. Six consecutive patients admitted with a diagnosis of adult peptic pyloric stenosis between November 1999 and August 2002 were studied. The diagnosis was confirmed with endoscopy. All patients were commenced on a twice-daily dose of intravenous PPI. This was changed to oral treatment after 2 days. Main outcome measures evaluated were resolution of symptoms on PPIs and failure of medical therapy.', 'There were five females and one male. Median age at diagnosis was 72 years (range, 30-90 years). Median duration of symptoms was 2 weeks (range, 1-5 weeks). Of the patients, five had a history of peptic ulcer disease. Complete resolution was achieved in 5 patients (83%). Median duration for resolution of symptoms was 9 days (range, 5-14 days). All patients were changed to oral PPIs after 2 days. One patient did not respond to oral therapy and required surgical intervention (pyloroplasty). Median follow-up was 26 months (range, 6-48 months). There was no recurrence of symptoms. All patients were discharged on low-dose PPI.\Question: Is proton pump inhibition a feasible primary alternative to surgery and balloon dilatation in adult peptic pyloric stenosis ( APS ) : report of six consecutive cases?

Answer: This study supports the view that proton pump inhibitors are a safe and feasible alternative to surgery in adult pyloric stenosis secondary to peptic ulcer disease.


Question: Context: Perls' stain is routinely used to demonstrate iron in liver biopsies. We tested the hypothesis that it may be unnecessary in cases, where no iron or another similar pigment was seen on the routine hematoxylin and eosin (H and E) stained section.", "The aim of this study was to evaluate the efficiency of H and E stain in demonstrating iron in liver biopsies as well as to determine the possibility of replacing Perls' stain with H and E stain.", "Two hundred pairs of slides of liver biopsies were taken from the archival files of the Department of Pathology from 2006 to 2011. Perls' and H and E slides were independently reviewed for the presence of iron.", "Hundred and one cases showed the presence of iron using H and E stain. 84 of 86 cases showed positive iron using both Perls' and H and E stains. Seventeen cases were positive using H and E stain but negative with Perls'. Only two cases did not show the presence of iron using H and E stain. Ninety-seven cases were negative using both Perls' and H and E stains. H and E stain showed a sensitivity, specificity, accuracy, positive predictive valve, and negative predictive value of 97.67%, 85.08%, 90.5%, 83.16%, and 97.98%, respectively.\Question: Do hematoxylin and eosin stain shows a high sensitivity but sub-optimal specificity in demonstrating iron pigment in liver biopsies?

Answer: We demonstrate that the H and E stain is a sensitive method to detect iron pigment in liver biopsies, particularly when present in large quantities. A negative H and E stain might obviate the need for extra Perls' staining, thus saving costs and shortening report turn-around times.


Question: Context: Internal carotid artery (ICA) stenosis can lead to cerebral hypoperfusion and is a common cause of stroke. As susceptibility weighted imaging (SWI) has been used for penumbra imaging in acute ischemic stroke, we aimed at analyzing hypoperfusion using SWI in patients with ICA stenosis.', 'Clinical characteristics, asymmetric cortical vessel sign (more and/or larger, hypointense asymmetric cortical vessels) on SWI, Doppler sonography results and diffusion weighted imaging (DWI) lesion volume were retrospectively analyzed in patients with ICA stenosis. In a subgroup of patients, volume of prolonged time to peak and volume of prolonged time to peak of the residue curve (Tmax) were measured as reference standard. Outcome was assessed as modified Rankin score at discharge.', '104 patients were included. Median age was 72 and median degree of stenosis 70% according to NASCET. 13% had a asymmetric cortical vessel sign. These patients had a higher degree of stenosis (80% vs. 70%, p=0.004), were more often symptomatic (93% vs. 61%, p=0.020) and had higher DWI volume (7.3ml vs. 0.2ml, p=0.011). Specificity for the prediction of DWI lesions was 86%. Also, patients with asymmetric cortical vessel sign had lower rates of favorable outcome (mRS=0-2; 57% vs. 82%, p=0.033) and volumes of Tmax≥4s, ≥6s, ≥8s, ≥10s and TTP≥2s, ≥4s, ≥6s were significantly higher. In multivariate analysis, asymmetric cortical vessel sign was an independent negative predictor of favorable outcome (mRS 0-2; OR 0.184; CI [0.039; 0.875] p=0.033).\Question: Does cortical vessel sign on susceptibility weighted imaging reveal clinically relevant hypoperfusion in internal carotid artery stenosis?

Answer:
In patients with ICA stenosis, asymmetric cortical vessel sign is a sign of clinically relevant hypoperfusion.