Given a passage, 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: Gastrin and pepsinogens reflect the functional state of the gastric mucosa.', 'To evaluate whether serum gastrin and pepsinogens correlate with the different grades of severity of gastro-oesophageal reflux disease (GERD).', "In all, 388 patients with heartburn not taking any form of acid suppressive therapy were matched-controlled for age and gender and sub-classified into four groups: group 1 non-erosive reflux disease (NERD); group 2, erosive reflux disease (ERD) Los Angeles (LA) A and B, group 3, ERD LA C and D; group 4 Barrett's oesophagus (BO). Fasting serum was analysed for gastrin 17, pepsinogen I, pepsinogen II und Helicobacter pylori using specific EIA tests (GastroPanel; Biohit, Plc).", 'Kruskal-Wallis test and analysis of variance.', 'There was a significant difference among the four groups with respect for pepsinogen I, but not for pepsinogen II, the pepsinogen I pepsinogen II ratio, H. pylori serology and gastrin levels. Pepsinogen I was the lowest in NERD and the highest in BO (median 91.6, mean +/- standard deviation 106.2 +/- 51.6 vs. median 114.7, mean +/- standard deviation 130.4 +/- 70.6; P = 0.046). Pepsinogen I levels were higher in H. pylori positive subjects. After adjusting for H. pylori status, the differences in pepsinogen I across patient groups were no longer statistically significant (P = 0.298).
Example Output: Do serum gastrin and pepsinogens correlate with the different grades of severity of gastro-oesophageal reflux disease : a matched case-control study?

Example Input: Total blood homocysteine (Hcys) and folate levels have been investigated in association with cognitive dysfunction in healthy but not in multimorbid elderly patients. We hypothesized that total serum Hcys is an adequate marker to identify multimorbid elderly patients with cognitive dysfunction assessed by the Short Cognitive Performance Test (SKT) and Mini-Mental State Examination (MMSE).', 'Cross-sectional study.', 'The study center was an acute geriatric hospital.', 'A total of 189 multimorbid elderly patients were recruited.', 'Cognitive dysfunction was determined according to the SKT and MMSE. Biochemical parameters (Hcys, folate, vitamin B12, hemoglobin), nutritional status (BMI, Mini Nutritional Assessment, nutritional intake), and activities of daily living were assessed.', 'According to the SKT, 25.4% of patients showed no cerebral cognitive dysfunction, 21.2% had suspected incipient cognitive dysfunction, 12.7% showed mild cognitive dysfunction, 9.0% had moderate cognitive dysfunction, and 31.7% of patients were demented. The median plasma Hcys value was elevated by approximately 20% in multimorbid elderly patients, independent of cognitive dysfunction. Serum folate and vitamin B12 concentrations were within normal ranges. We did not find significant differences in nutritional status, activities of daily living, numbers of diseases or medications, or selected biochemical parameters between the SKT groups.
Example Output: Do total serum homocysteine levels identify cognitive dysfunction in multimorbid elderly patients?

Example Input: Enhancing thrombus resolution may reduce the long-term complications of venous thrombosis. The aim of this study was to examine whether a sustained release of vascular endothelial growth factor (VEGF) would further improve thrombus recanalization.', 'Inferior caval vein thrombosis was induced in a cohort of 21 male Wistar rats. A plasmid encoding the human VEGF gene (phVEGF) was injected directly into thrombus (30 to 50 microg) and the muscle adjacent to the inferior vena cava (300 to 400 microg). A plasmid containing the gene encoding beta-galactosidase (pCMVbeta) was injected into the same sites of a separate cohort of rats to act as a control. Tissues were harvested after 1 and 2 weeks, and beta-galactosidase activity was measured to estimate transfection efficiency. Muscle and serum VEGF were measured by enzyme-inked immunosorbent assay. Thrombus size, recanalization, and organization were determined by computer-assisted image analysis.', 'The efficiency of control plasmid transfection into muscle was about 1%. No serum hVEGF was detected in phVEGF- or pCMVbeta-treated animals. Significantly raised levels of hVEGF (P < .01) were detected in the muscle injected with phVEGF after 2 weeks compared with control muscle. There was a significant reduction in thrombus size of 23% (P < .05) and 48% (P < .001) in phVEGF-treated animals compared with pCMVbeta-treated controls after 1 and 2 weeks, respectively. Thrombus recanalization was a significantly greater in the phVEGF-treated group after 2 weeks (mean 19% +/- 2% [SEM]) compared with controls (mean 13% +/- 2%, P < .01). There were no differences in the thrombus organization score.
Example Output:
Does vascular endothelial growth factor naked DNA gene transfer enhance thrombus recanalization and resolution?