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.

Context: Diagnosis of partial anomalous pulmonary venous return is usually suspected by echocardiography and often confirmed by cardiac catheterization. Magnetic resonance imaging is a powerful non-invasive diagnostic tool that can give accurate insight on systemic and pulmonary veins, cardiac anatomy and physiopathology.', 'To test the diagnostic accuracy of magnetic resonance in patient with suspected partial anomalous pulmonary venous return.', 'Twenty consecutive patients (10 male, mean age: 27+/-20 years) with suspected partial anomalous pulmonary venous return underwent a magnetic resonance study comprehensive of Gadolinium-enhanced three-dimensional magnetic resonance angiography and phase-velocity-contrast in order to evaluate pulmonary and systemic venous anatomy and QP/QS. In 14 of them a cardiac catheterization was also performed. Anatomy findings and QP/QS result of both exams were compared. Sixteen patients underwent surgical correction. In the other four patients with QP/QS<1.5, surgical correction was not indicated according to the literature (1). Among patients who had both magnetic resonance and cardiac catheterization (14 patients) anatomical findings were concordant in 12 of them. In all operated patients, surgical findings were concordant with MRI report. There was a good correlation between magnetic resonance and cardiac catheterization QP/QS evaluation (mean value 2.23 and 2.4, respectively).
Answer: In patients with suspected anomalous pulmonary venous return, magnetic resonance provides a comprehensive evaluation of pulmonary venous return and the amount of shunt, overcoming most of the limitations of echocardiography. Therefore magnetic resonance is a powerful diagnostic tool for indicating therapeutic management and surgical strategies for this group of patients, and can be considered a non-invasive alternative to cardiac catheterization.
Is magnetic resonance imaging the diagnostic tool of choice in the preoperative evaluation of patients with partial anomalous pulmonary venous return?

Context: Stomatal guard cells monitor and respond to environmental and endogenous signals such that the stomatal aperture is continually optimised for water use efficiency. A key signalling molecule produced in guard cells in response to plant hormones, light, carbon dioxide and pathogen-derived signals is hydrogen peroxide (H(2)O(2)). The mechanisms by which H(2)O(2) integrates multiple signals via specific signalling pathways leading to stomatal closure is not known.', 'Here, we identify a pathway by which H(2)O(2), derived from endogenous and environmental stimuli, is sensed and transduced to effect stomatal closure. Histidine kinases (HK) are part of two-component signal transduction systems that act to integrate environmental stimuli into a cellular response via a phosphotransfer relay mechanism. There is little known about the function of the HK AHK5 in Arabidopsis thaliana. Here we report that in addition to the predicted cytoplasmic localisation of this protein, AHK5 also appears to co-localise to the plasma membrane. Although AHK5 is expressed at low levels in guard cells, we identify a unique role for AHK5 in stomatal signalling. Arabidopsis mutants lacking AHK5 show reduced stomatal closure in response to H(2)O(2), which is reversed by complementation with the wild type gene. Over-expression of AHK5 results in constitutively less stomatal closure. Abiotic stimuli that generate endogenous H(2)O(2), such as darkness, nitric oxide and the phytohormone ethylene, also show reduced stomatal closure in the ahk5 mutants. However, ABA caused closure, dark adaptation induced H(2)O(2) production and H(2)O(2) induced NO synthesis in mutants. Treatment with the bacterial pathogen associated molecular pattern (PAMP) flagellin, but not elf peptide, also exhibited reduced stomatal closure and H(2)O(2) generation in ahk5 mutants.
Answer: Our findings identify an integral signalling function for AHK5 that acts to integrate multiple signals via H(2)O(2) homeostasis and is independent of ABA signalling in guard cells.
Does the histidine kinase AHK5 integrate endogenous and environmental signals in Arabidopsis guard cells?

Context: Overweight and obese individuals are more likely to be insulin resistant and at increased risk of adverse clinical outcomes. Questions remain as to whether waist circumference (WC) or body mass index (BMI) most effectively identifies insulin-resistant individuals.', 'This study quantified insulin-mediated glucose uptake (IMGU) in 330 apparently healthy volunteers and compared the relation between this value and measurements of WC and BMI.', 'IMGU was quantified via determination of the steady-state plasma glucose (SSPG) concentration during the insulin-suppression test. Differences in SSPG concentrations due to variations in WC within a given BMI category, as well as those due to differences in BMI within a given WC classification, were then compared.', 'BMI and WC correlated with each other (r = 0.78, P < 0.001) and equally with SSPG concentrations (r = 0.58 and 0.57, respectively; P < 0.001). When stratified by BMI, abdominally obese subjects within the overweight BMI category had higher SSPG concentrations than did those with a normal WC (P < 0.05). When classified by WC, subjects in the overweight BMI category had greater SSPG concentrations than did subjects in the normal BMI category within the normal WC category (P < 0.01), as did subjects in the obese BMI category in comparison with subjects in the overweight BMI category within the obese WC category (P < 0.01).
Answer: The more overweight or obese a person, the greater the degree of insulin resistance; differences in adiposity accounted for approximately one-third of the variation in IMGU, irrespective of the index used. Furthermore, there was no difference in the relation between the degree of insulin resistance and either index of adiposity.

Do body mass index and waist circumference both contribute to differences in insulin-mediated glucose disposal in nondiabetic adults?