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.

[Q]: Changes of volume status can be readily inferred from variations in diameter of the inferior vena cava (IVC) measured by ultrasound. However the effect of IVC changes following acute blood loss are not fully established. In this study, three different approaches to measuring IVC variables were compared in healthy blood donors, as a model of acute volume depletion, in order to establish their relative ability to detect acute blood loss.', 'Inspiratory and expiratory IVC diameters were measured before and after blood donation in hepatic long axis, hepatic short axis and renal short axis views using a 2-5MHz curvilinear probe. All measurements were recorded and examined in real-time and post-processing sessions.', 'All windows performed satisfactorily but the renal window approach was feasible in only 30 out of 47 subjects. After blood donation, IVC diameters decreased in hepatic long axis, hepatic short axis and renal short axis (expiratory: -19.9, -18.0, -26.5%; CI 95%: 14.5-24.1; 13.1-22.9; 16.0-35.9, respectively) (inspiratory: -31.1, -31.6, -36.5%; CI 95%: 21.3-40.1; 18.8-45.2; 23.4-46.0, respectively), whereas the IVC collapsibility index increased by 21.6, 22.6 and 19.3% (CI 95%: 11.6-42.9; 18.5-39.5; 7.7-30.0). IVC diameters appeared to return to pre-donation values within 20min but this was only detected by the hepatic long axis view.
[A]: Do inferior vena cava diameters and collapsibility index reveal early volume depletion in a blood donor model?

[Q]: Cocaine and alcohol are frequently used simultaneously and this combination is associated with enhanced toxicity. We recently showed that active cocaine abusers have a markedly enhanced sensitivity to benzodiazepines. Because both benzodiazepines and alcohol facilitate GABAergic neurotransmission we questioned whether cocaine abusers would also have an enhanced sensitivity to alcohol that could contribute to the toxicity. In this study we compared the effects of alcohol (0.75 g/kg) on regional brain glucose metabolism between cocaine abusers (n = 9) and controls (n = 10) using PET and FDG. Alcohol significantly decreased whole brain metabolism and this effect was greater in controls (26+/-6%) than in abusers (17+/-10%) even though they had equivalent levels of alcohol in plasma. Analysis of the regional measures showed that cocaine abusers had a blunted response to alcohol in limbic regions, cingulate gyrus, medial frontal and orbitofrontal cortices.
[A]: Do cocaine abusers show a blunted response to alcohol intoxication in limbic brain regions?

[Q]: Children with residual brachial plexus birth palsy often develop internal rotation contractures with subsequent glenohumeral dysplasia seen on axial imaging. Coronal deformity (characterized by humeral head subluxation), and angular deformity (characterized by glenoid retroversion) have been defined. We hypothesize that the location of the biceps tendon characterizes rotational deformity.', 'A retrospective study was performed on 91 children (average age 3.2+/-2.2 y) who lacked external rotation beyond neutral and had magnetic resonance imaging (MRI) scans of bilateral shoulders performed at our institution between 2000 and 2007. The charts were reviewed for the measurement of the external rotation of the involved shoulder with the arm adducted and the scapula stabilized. The glenoscapular angle (glenoid version), the percentage of the humeral head anterior to the middle of the glenoid fossa (PHHA), and the angle of rotation of the biceps tendon (biceps angle) were measured on MRI scans of both shoulders. Statistical analysis was performed to compare these MRI measurements for the involved and uninvolved sides, and to identify the correlations between them and the external rotation.', 'The average biceps angle was 47.9+/-15.2 degrees on the uninvolved side and 26.2+/-15.0 degrees on the involved side. The average differences between the 2 shoulders in the biceps angle (21.7+/-20.5 degrees), the version (18.9+/-15.0 degrees), and the PHHA (19.8+/-13.6%) were all significant (P<0.001). Only the biceps angle correlated significantly with external rotation (P<0.001). This correlation remained significant even when the version and the PHHA were held constant (P=0.004).
[A]:
Do the biceps tendon as a measure of rotational deformity in residual brachial plexus birth palsy?