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.

Example Input: Leaks of the blood-brain barrier can be detected on postcontrast-enhanced T1-weighted MRIs. Although early disruptions of the blood-brain barrier appear to be an important risk factor for tissue plasminogen activator-related hemorrhages in rodents, little is known about their incidence and consequences in human stroke.', "This is a retrospective analysis of a prospectively collected stroke database over the past 6 years. In 52 patients, multimodal MRI (including diffusion-weighted, perfusion-weighted, and postcontrast-enhanced T1-weighted MRI to detect blood-brain barrier changes) had been performed immediately before systemic thrombolysis and in 48 patients within a median of 30 minutes (interquartile range: 30 to 60 minutes) after recombinant tissue plasminogen activator treatment. The incidence of symptomatic hemorrhage (SICH), defined as any parenchymal hemorrhage leading to deterioration in the patient's clinical condition, was related to several clinical and imaging variables, including early blood-brain barrier changes.", 'Overall, SICH was detected in 9 (9%) patients and among these, 2 died. Although no blood-brain barrier changes were detectable before thrombolysis, 3 of 48 patients (6.25%) had a parenchymal gadolinium enhancement in the areas of initial infarction after tissue plasminogen activator treatment. All 3 patients developed SICHs at sites corresponding to the areas of enhancement. The presence of a parenchymal enhancement was significantly associated with SICH (P<0.01), whereas other clinical and imaging variables did not predict SICH in this series.
Example Output: Does early disruption of the blood-brain barrier after thrombolytic therapy predict hemorrhage in patients with acute stroke?

Example Input: In this study, we examined chondrogenic regulation of 2 types of mesenchymal stem cells seeded on the bioengineered substrate in monolayer cultures under mechanically defined conditions to mimic the in vivo microenvironment of chondrocytes within articular cartilage tissues.', 'Human adipose-derived mesenchymal stem cells (ASCs) and bone marrow mesenchymal stem cells (BSCs) were exposed to 0.2 Pa shear stress, 3 MPa cyclic hydrostatic pressure, and combined loading with different sequences on chemically designed medical-grade silicone rubber, while no soluble growth factors were added to the culture medium. The expression levels of chondrogenic-specific genes of SOX9, aggrecan, and type II collagen (Col II) were measured. Results were compared to those of cells treated by biological growth factor.', 'Gene expression patterns were dependent on the loading regime. Moreover, the source of mesenchymal stem cells (adipose or bone marrow) was influential in gene expression. Overall, enhanced expression of chondrogenic markers was found through application of mechanical stimuli. The response was generally found to be significantly promoted when the 2 loading regimes were superimposed.
Example Output: Do the synergistic effects of shear stress and cyclic hydrostatic pressure modulate chondrogenic induction of human mesenchymal stem cells?

Example Input: Patients with systemic lupus erythematosus (SLE) frequently suffer from infections, but the predisposing risk factors, as well as the exact frequency and nature of such infections, are not fully understood.', 'To describe the frequency, types and risk factors for infections in a group of Chinese patients in the early stage of SLE in Hong Kong.', 'Retrospective record study.', 'We reviewed the case records of 91 Chinese SLE patients, presenting <12 months after SLE diagnosis. Details of major infections (requiring intravenous antimicrobial therapy, or any confirmed mycobacterial infection) and minor infections were reviewed. Clinical and laboratory features, the systemic lupus erythematosus disease activity index (SLEDAI) at presentation and drug treatment were recorded and analysed.', 'There were 48 major infections and 62 minor infections during 260 patient-years of follow-up. A lymphocyte count < or =1.0 x 10(9)/l at presentation was independently associated with an increased risk for major infection: hazard ratio 4.7 (95%CI 1.6-13.7), p = 0.005. SLEDAI, use of corticosteroids and immunosuppressive therapy were all not associated with increased risk of infection.
Example Output:
Is lymphopenia at presentation associated with increased risk of infections in patients with systemic lupus erythematosus?