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.

Example Input: Context: The aim of this study was to investigate the relationship between intraoperative vasopressin infusion and postoperative cardiac enzymes.', 'A prospective, double-blind, randomized, controlled study.', 'A single tertiary cardiac center.', 'One hundred consecutive patients undergoing cardiac surgery with or without cardiopulmonary bypass.', 'The study was approved by the Institutional Review Board, and patients provided informed consent to participate. Patients were randomized by computer into 2 equal groups: Vasopressin or control. The blinded study included vasopressin administered at a dose of 1.8 U/h or 1.8 mL/h of normal saline, along with catecholamines. The drug was administered continually during surgery while patients needed catecholamines. The intervention was discontinued upon admission to the intensive care unit when information regarding the true character of the drug was reported to the doctor in charge of patients in the intensive care unit by one of the investigators. Primary outcomes were CK-MB and troponin T levels measured at 0, 6, and 12 hours postoperatively.', 'Of the 100 patients, 8 were excluded; the remaining 92 were randomized to either the vasopressin (n = 47) or control (n = 45) group. There were no significant differences in demographic data between the groups. Postoperatively at 0, 6, and 12 hours, there were no differences in CK-MB (U/l) (37.5 ± 57.9 v 32.0 ± 21.5, 29.4 ± 41.1 v 24.4 ± 23.1, and 21.4 ± 21.3 v. 21.8 ± 32.4, respectively) and troponin T (752.4 ± 638.2 v 762.7 ± 557.1, 753.8 ± 507.3 v 777.6 ± 515.0, and 774.6 ± 572.6 v 698.7 ± 540.2, respectively) values.
Answer: Vasopressin infusion has been used to treat catecholamine-unresponsive shock. In this study, intraoperative vasopressin was used safely as a possible first-line drug for treating hypotension; however, it did not increase the levels of cardiac enzymes after cardiac surgery.
Example Output: Does vasopressin raise cardiac enzymes following cardiac surgery : a randomized double-blind clinical trial?

Example Input: Context: Hepatic resection is well established as a potentially curative treatment for hepatic colorectal cancer metastases. However, only a small proportion of patients with liver metastases are suitable for resection because they either have extrahepatic disease, or the extent and/or the distribution of their hepatic disease would make excision impossible. We have previously described the use of cryotherapy for inadequate resection margins and lesions in the remaining lobe of the liver. Combining such cryodestructive techniques with resection offers the possibility of increasing the proportion of patients to whom potentially curative treatment can be offered. The aim of this study was to compare survival in patients treated with resection and cryotherapy against those of patients treated with resection alone. Potential prognostic variables were also examined.', 'Patients undergoing a hepatic resection with or without cryotherapy at our unit between April 1990 and July 1997 were identified from our database and their notes reviewed. Survival was estimated using the Kaplan-Meier method and compared using the Log rank test.', 'One hundred and seven patients were treated in total: 32 underwent resection alone, and 75 underwent resection combined with cryotherapy. There was no significant difference between the survival of patients treated with resection alone and those treated with resection and cryotherapy.
Answer: Edge and contralobe cryotherapy can be combined with hepatic resection to allow a greater proportion of patients with hepatic colorectal metastases to be offered treatment, and results in similar survival figures comparable to hepatic resection for at least 3 years.
Example Output: Does resection with cryotherapy of colorectal hepatic metastases have the same survival as hepatic resection alone?

Example Input: Context: Cardiovascular disease contributes to excess morbidity and mortality in HIV infection, and endothelial dysfunction may contribute to this pattern. We aimed to determine the endothelial function in treated and untreated HIV-infected individuals and investigate potential associations with viral replication, immune activation, coagulation, platelet function, and subclinical atherosclerosis.', 'Asymmetric dimethylarginine (ADMA, marker of endothelial dysfunction) and soluble CD14 (sCD14, marker of monocyte activation) were measured in plasma from two previously established cross-sectional cohorts: cohort A including 50 untreated and 50 antiretroviral therapy (ART)-treated HIV-infected individuals with previously assessed coagulation and platelet function and cohort B including 105 HIV-infected individuals on ART and 105 uninfected controls with previously assessed coronary artery calcium score, myocardial perfusion defects, and carotid intima-media thickness.', 'Concentrations of ADMA were higher in HIV-infected individuals compared with uninfected controls, and higher ADMA was found in ART-treated compared with untreated HIV-infected individuals. ADMA was associated with viral load, sCD14, D-dimer, and low CD4 T-cell count in untreated HIV infection. Only viral load remained significant in multivariate analyses. In ART-treated HIV-infected individuals, ADMA was not associated with coronary artery calcium score, myocardial perfusion defects, or intima-media thickness.
Answer: Evidence of endothelial dysfunction was found in HIV infection and in untreated compared with treated HIV infection. In untreated HIV infection, the main driver of endothelial dysfunction was viral replication. Importantly, in treated HIV infection, ADMA was not associated with subclinical atherosclerosis. Thus, our data question the potential of ADMA as a useful biomarker of early atherosclerosis in treated HIV infection.
Example Output:
Does marker of Endothelial Dysfunction Asymmetric Dimethylarginine be Elevated in HIV Infection but Not Associated With Subclinical Atherosclerosis?