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 Q]: Context: Impaired endothelial function, as assessed by brachial artery flow-mediated dilation (FMD), is an established risk factor for cardiovascular events. FMD is impaired in heart failure (HF) patients, but less is known about hyperemic brachial artery flow. We investigated the relationship between FMD and hyperemic flow with adverse clinical outcomes in HF patients.', 'Brachial artery FMD and hyperemic flow were assessed in 156 patients (70.5 % Male; 45.5% Caucasian; mean age ( SD) = 56.2 (12.4) years) with HF and reduced left ventricular ejection fraction (LVEF). Cox proportional hazard models were used to assess the potential explanatory association of FMD and hyperemic flow with the composite outcome of death or cardiovascular hospitalization over a median 5-year follow-up period.', 'Both FMD and hyperemic flow were negatively correlated with age, but unrelated to sex, race, body mass index, LVEF or N-terminal pro-B-Type natriuretic peptide (NT-ProBNP). Reduced hyperemic flow, but not FMD, was associated with an increased risk of death or cardiac hospitalization after controlling for traditional risk factors.
Answer: The association of reduced hyperemic flow with increased risk of adverse clinical outcomes suggests that micro-vascular function may be an important prognostic marker in patients with HF.
[EX A]: Is reactive hyperemia associated with adverse clinical outcomes in heart failure?

[EX Q]: Context: Anti-Mullerian hormone (AMH) may have a role in disordered folliculogenesis in polycystic ovary syndrome (PCOS). Though there have been several investigations into circulating AMH levels in patients with PCOS, no previous studies have compared AMH concentrations in the follicular fluid of unstimulated ovaries in women with PCOS with that of normally ovulating women.', 'Follicular fluid was aspirated from 4-8-mm follicles of unstimulated ovaries during routine laparoscopy or laparotomy from women with anovulatory PCOS (n = 11) and those with regular ovulatory cycles (n = 8). Follicular AMH was compared in the two groups. Serum samples were analysed for AMH and endocrine profile.', 'Follicular fluid AMH levels were significantly higher (P < 0.0001) in women with anovulatory PCOS (median: 466.2 ng/ml) compared with normal-ovulatory controls (median: 78.0 ng/ml). Mean follicular fluid AMH levels in PCOS patients were 60 times higher than in the serum. Moreover, there was a significant correlation between the follicular fluid and serum concentrations of AMH in the PCOS group (r = 0.86; P = 0.007) but not in controls.
Answer: Highly elevated AMH in follicular fluid from PCOS patients in contrast to age-matched normal controls suggests that increased circulating concentrations of AMH are partly due to the increased production of AMH by individual follicles and not simply attributable to the increased number of small antral follicles. This suggests an intrinsic abnormality in the ovarian follicles themselves in PCOS, which could contribute to disordered folliculogenesis.
[EX A]: Is anti-Mullerian hormone increased in follicular fluid from unstimulated ovaries in women with polycystic ovary syndrome?

[EX Q]: Context: Controversy exists as to whether polyethylene (PE) penetration of hip prostheses is underestimated when the measurements are made on radiographs obtained in supine position as compared to weight-bearing position.', 'We examined 111 patients by radiostereometric analysis (RSA) in the supine and weight-bearing positions.', 'The mean 3-D penetration was 0.68 mm (SD 0.58, range 0.04-3.05) for the supine position and 0.70 mm (SD 0.57, range 0.08-3.01) for the weight-bearing position. The correlation between supine and weight-bearing examinations was 0.99 (p < 0.001). The degree of penetration made no difference. There was no statistically significant difference as to whether the first examination was performed early, i.e. after 3 months, or after 12 months (p = 0.7).
Answer: The small systematic difference in penetration values between the supine and the weight-bearing positions is of no clinical or methodological importance.
[EX A]:
Are weight bearing radiographs necessary for measurement of polyethylene penetration in total hip prostheses : a radiostereometric study of 111 patients examined in weight-bearing and supine position?