Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Ex Input:
Context: Current diagnostic tests for gastroesophageal reflux disease (GERD) do not consistently measure chronicity of reflux. Mucosal impedance (MI) is a minimally invasive measurement to assess esophageal conductivity changes due to GERD. We aimed to investigate MI pattern in patients with symptoms of extraesophageal reflux (EER) in a prospective longitudinal cohort study.', 'Patients with potential symptoms of EER undergoing esophagogastroduodenoscopy (EGD) with wireless pH monitoring were studied. Participants included those with erosive esophagitis (E+), normal EGD/abnormal pH (E-/pH+), and normal EGD/normal pH (E-/pH-). MI was measured from the site of injury in patients with E+, as well as at 2, 5, and 10 cm above the squamocolumnar junction (SCJ) in all participants.', 'Forty-one patients with symptoms of EER were studied. MI measurements at 2cm above the SCJ were significantly (P=0.04) different among the three groups, with MI lowest for E+ and greatest for E-/pH- patients. Although not statistically significant, there is a graded increase in median (interquartile range) MI axially along the esophagus at 5cm (P=0.20) and at 10cm (P=0.27) above the SCJ, with those with reflux (E+ and E-/pH+) having a lower MI than those without.
Answer: Patients with symptoms of EER and evidence of acid reflux have an MI lower than those without at 2cm above the SCJ, with a trend at 5cm and 10cm as well. MI may be a tool to assess presence of GERD in patients presenting with EER symptoms.

Ex Output:
Is esophageal Mucosal Impedance Pattern Distinct in Patients With Extraesophageal Reflux Symptoms and Pathologic Acid Reflux?

Ex Input:
Context: The necessity for general anesthesia represents an impediment to using a laparoscopic approach for some procedures that are otherwise performed with the patient under local anesthesia using a conventional open technique. Heating and humidifying the insufflation gas reportedly reduces perioperative pain associated with a CO2 pneumoperitoneum, thus enabling awake laparoscopy.', 'Two cases are reported herein of laparoscopy performed with the patient under local anesthesia using heated, humidified CO2 gas for the pneumoperitoneum.', 'Both patients experienced pain with insufflation of heated, humidified CO2 gas of sufficient magnitude that the procedure could not be performed. The CO2 gas was washed out and replaced with helium gas insufflation with complete resolution of pain. The laparoscopic procedures were accomplished without further discomfort with local anesthesia and using a helium gas pneumoperitoneum.
Answer: Heated, humidified CO2 gas insufflation does not reduce pain sufficiently to permit satisfactory performance of laparoscopy with local anesthesia, especially when full volume insufflation is required. Cold, dry helium gas produces no pain. The theory that cold, dry insufflation gas is a source of peritoneal pain during laparoscopy needs to be reassessed.

Ex Output:
Is heated , humidified CO2 gas unsatisfactory for awake laparoscopy?

Ex Input:
Context: Sequential events of endometrial tumorigenesis can be studied by comparison of genetic lesions seen in normal, premalignant, and malignant tissues. The distribution of k-ras mutations in microsatellite stable and unstable premalignant lesions was studied to determine whether this gene is implicated in both tumorigenic pathways.', 'K-ras mutations were analysed by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and direct sequencing in matched endometrial normal, premalignant (atypical hyperplasias), and adenocarcinoma tissues from individual patients. Identification of precancers solely by their appearance as atypical endometrial hyperplasias is very subjective; therefore, in addition to histopathological assessment, we performed molecular testing (non-random X inactivation or clonal altered microsatellites) for an expected feature of precancers--that is, monoclonality.', 'Equivalent K-ras mutation frequencies were seen in microsatellite stable (six of 33) and unstable (three of 23) cancers. In both types, K-ras mutation in monoclonal precancers usually corresponded to a change from normal to an equivocal (two of 12) or hyperplastic (10 of 12) histology. Divergent K-ras genotypes among multiple neoplastic tissues of individual patients (two of six patients) are exceptions explained either by multicentric premalignant disease, or acquisition of K-ras mutation late in neoplastic progression.
Answer: K-ras mutation occurs in both premalignant microsatellite stable and unstable endometrial neoplasia, sometimes before acquisition of features readily diagnostic as atypical endometrial hyperplasia.

Ex Output:
Do k-ras mutations appear in the premalignant phase of both microsatellite stable and unstable endometrial carcinogenesis?