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.
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Question: Context: This study evaluated risk factors for acute wheeze in preschool children and investigated whether subnormal levels of vitamin D were associated with increased risk for acute wheeze, atopy or viral/bacterial respiratory infections.', 'We recruited 130 children with acute wheeze, aged 6\xa0months to 4\xa0years, from paediatric emergency departments in Stockholm, Sweden, and 101 age-matched controls with no history of wheeze or sensitisation to airborne allergens. Parents answered standardised questionnaires, and blood samples were analysed for specific IgE to airborne and food allergens and levels of 25 hydroxyvitamin D (25(OH)D). Nasopharyngeal virus samples were collected during the emergency department visit in the group of children with wheeze, and a subset were also tested for bacteria.', 'Vitamin D insufficiency (25(OH)D\xa0<\xa075\xa0nmol/L (30\xa0ng/mL)) was associated with an odds ratio of 2.7 (95% confidence interval 1.1-6.2) for acute wheeze. However, no association was found between vitamin D insufficiency and atopy, presence of virus or bacteria or recurrent infections. Children older than 24\xa0months were particularly at risk of subnormal vitamin D levels, irrespective of wheezing history.
Answer: Our findings support the hypothesis that subnormal levels of vitamin D are associated with acute wheeze in young children.

Answer: Are subnormal levels of vitamin D associated with acute wheeze in young children?


Question: Context: To investigate the significance of respiratory muscle weakness in chronic heart failure and its relation both to maximum oxygen consumption during cardiopulmonary exercise testing and to skeletal muscle (quadriceps) strength.', 'Seven healthy men aged 54.9 (SEM 4.3) years and 20 men with chronic heart failure aged 61.4 (1.6) years (P = 0.20) with radionuclide left ventricular ejection fraction of 25.4 (3.0)%.', 'Mouth pressures during maximum static inspiratory effort (PImax) at functional residual capacity (FRC) and residual volume (RV) were measured in all subjects and taken as indices of inspiratory muscle strength. Similarly, mouth pressures during maximum static expiratory effort (PEmax) at FRC and total lung capacity (TLC) were taken as indices of expiratory muscle strength. Cardiopulmonary exercise testing was performed in all subjects. All controls and 15 heart failure patients also had their right quadriceps muscle strength measured.', 'There was respiratory muscle weakness in heart failure patients, with reduction of PImax at FRC (59.7) (6.3) v 85.6 (9.6) cm H2O, P = 0.045), PEmax at FRC (94.8 (6.2) v 134.6 (9.1) cm H2O, P = 0.004), and PEmax at TLC (121.7 (8.5) v 160.7 (13) cm H2O, P = 0.028). PImax at RV was also reduced but this did not reach statistical significance (77.3 (6.6) v 89.3 (13) cm H2O, P = 0.44). There was also significant weakness of the right quadriceps muscle (308.5 (22) v 446.2 (28) N, P = 0.001). PImax at both FRC and RV correlated with maximum oxygen consumption (r = 0.59, P = 0.006, and r = 0.45, P = 0.048 respectively) but not PEmax. There was, however, no significant correlation between PImax and right quadriceps strength.
Answer: Respiratory muscle weakness is seen in chronic heart failure. The results suggest that inspiratory muscles are important in determining maximum oxygen consumption and exercise tolerance in these patients. The lack of correlation between respiratory and right quadriceps muscle strength further suggests that the magnitude and time course of respiratory and locomotor muscle weakness may differ in individual patients. Treatment aimed at improving the function of the involved muscle groups may alleviate symptoms.

Answer: Is inspiratory muscle strength a determinant of maximum oxygen consumption in chronic heart failure?


Question: Context: Meckel's diverticulum (MD) is the most common congenital anomaly of the gastrointestinal tract. Although a majority of patients remain asymptomatic, complications may occur in a subset of patients. MD is a rare cause of gastrointestinal bleeding (GIB) in adults. We aimed to clarify the possible role of capsule endoscopy (CE) in the identification of Meckel's diverticulum.", 'From October 2004 to December 2010, 157 CEs were performed (83 male individuals, mean age 51±20 years; range 3-83 years) for obscure GIB. Before CE, all patients underwent nonconclusive upper and lower endoscopy at least two times and barium follow-through.', 'CE identified the source of bleeding in 70/157 patients (44.6%). MD was diagnosed in 13/70 (18.6%) patients (11 male individuals, mean age 35±20 years, range, 3-69 years) after CE. Nine patients presented with obscure overt and four with obscure occult bleeding. The mean duration of obscure GIB history was 13 months (range 1-72 months). The mean hemoglobin concentration at the time of the procedure was 115±12\u2009g/l. The findings of MD on CE were double lumen sign (13/13), visible blood (7/13), and diaphragm sign (6/13). All patients were operated upon, and MD histologically verified in 11. In two patients CE was false-positive and in two patients, false-negative. Capsule endoscopy had a positive predictive value of 84.6% for the diagnosis of MD.
Answer: MD should be considered in the differential diagnosis of obscure GIB in adults. CE is an effective and promising modality for diagnosing MD in patients with obscure GIB.

Answer:
Is capsule endoscopy useful diagnostic tool for diagnosing Meckel 's diverticulum?