instruction:
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.
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?

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Context: The aim of this study was to visualize early stage prostate cancer (Cap) in a clinical setting. In previous studies, the results of magnetic resonance imaging (MRI) for screening Cap have rarely been confirmed by well-designed multisite prostate biopsy.', 'The prostate glands of 90 men with elevated prostate-specific antigen (PSA) were imaged by dynamic contrast-enhanced MRI (DCE-MRI) before transrectal ultrasound-guided 14-cores prostate biopsy. Each core was divided into three subcore fractions (total of 42 fractions) to generate a histological localization diagram, which was compared with localization-visualized DCE-MRI.', "The detection rate of Cap in 57 patients with PSA < 10.0 ng/ml was 36.8% as determined by the initial biopsy. DCE-MRI uncovered 92.9% of the clinically significant Caps and its specificity was 96.2% for the first biopsy session. One case with positive DCE-MRI and a negative primary biopsy was positive with additional biopsies. All of 26 DCE-MRI positive cases had significant Cap, and two of eight patients with histological Cap and negative or equivocal imaging had significant cancer. In total, 9 of 20 cases with DCE-MRI stage T2 underwent radical prostatectomy. All of them had organ-confined disease, although 33-77% (mean 63%) of them were expected to be rated T3 or higher by Partin's table.
Answer: DCE-MRI can identify early stage Cap with high sensitivity and specificity, and can predict the histological grade to some extent. DCE-MRI prior to biopsy should be applied to younger patients with surgical indications. Otherwise, we recommend the definitive diagnosis of Cap by utilizing DCE-MRI alone.
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Is dynamic contrast-enhanced magnetic resonance imaging ( DCE-MRI ) a useful modality for the precise detection and staging of early prostate cancer?

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Context: Elevated myeloperoxidase (MPO) levels are predictive of high cardiovascular (CV) risk in the general population. The value of MPO as a CV marker in the HIV population has not been investigated.', 'Medical records were reviewed to identify HIV+ patients with a documented CV event (myocardial ischemia/infarction) and stored plasma samples within 12 months prior to the event. HIV+ adults with no CV history and with similarly available stored plasma samples were site-, age-, and gender-matched 1:1 to cases.', 'We identified 124 participants (62 case-control pairs): 94% male, median age 46 years. Median (IQR) MPO levels (pmoles/L) were lower in cases vs. controls: 292 (235-376) vs. 320 (249-467); p= .004. Cases were more likely to have other CV risk factors, including smoking, hypertension, and higher cholesterol and triglycerides. The observed MPO directional difference persisted after controlling for CV risk factors. In the reduced model, observed differences in MPO remained independently and negatively associated with CV event (p= .03) after adjusting for two positively associated risk factors, differences in cholesterol levels (p= .01), and differences in smoking history (ever smoked vs. never smoked; p= .04). Differences in triglyceride levels and hypertension were not statistically significant independent risk factors in this sample (p> .05). Within cases, MPO was negatively correlated with CD4 count (rs= -0. 40, p= .0023) and age (rs= -0. 34, p= .01). In contrast, age at blood draw was positively correlated with MPO in controls (rs= 0.28, p= .031) and CD4 was uncorrelated (rs= -0. 01, p> .9). No other factors were significantly correlated with MPO within groups.
Answer: In contrast to the general population, higher MPO levels were not predictive of CV events in this study, underscoring the fact that pathways operative in HIV arteriopathy may be distinct from traditional CV disease pathogenesis.
answer:
Are higher plasma myeloperoxidase levels associated with an increased risk for cardiovascular events in HIV-infected adults?