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.

Q: Context: We evaluated the impact of impermeable bed covers on asthma in asthmatics with clinically relevant house dust mite (HDM) sensitization.', 'The study included 32 HDM-sensitized asthmatics in whom HDM allergy was considered as a significant factor in their asthma. They were randomized into either an intervention group whose bedding was encased with impermeable covers, or a control group who received cotton covers. Before and 3 and 6 months after encasement, dust samples were collected from the bedding and assayed for Der p 1. Clinical outcomes included quality of life, lung function, bronchial reactivity to methacholine, symptoms, medications and peak flow rates.', 'Baseline Der p 1 levels in both the active and the placebo groups were comparable and high (19.2 vs 18.9 microg/g of dust). There was a significant reduction in Der p 1 levels in the active group after 6 months, but not in the placebo group (7.3 vs 21.9 microg/g of dust). Quality of life improved significantly in both the intervention and control groups, but there was no significant difference in the improvements between the groups. There was no significant change in lung function, symptoms, and requirements for medications.
Answer: Encasement of bedding significantly reduced the Der p 1 levels. However, this was not sufficient to produce worthwhile clinical improvement in those in whom dust mite avoidance might well have been recommended as part of their clinical management.

A: Does encasement of bedding improve asthma in atopic adult asthmatics?
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Q: Context: Objective analysis of surgical skill is necessary. A novel method of assessment using simple error analysis in synthetic models is examined for construct validity.', 'Two examination protocols were devised using synthetic models. These contained either a purpose made error or were representative of good surgical practice. Protocol one contained models of skin closure and minor operations. Protocol two in addition more complex procedures. Face validity was established by the approval of senior surgeons. Junior surgeons were recruited to undertake the assessment. A p value of less than 0.05 was deemed to be significant.', 'Eighty-nine surgeons were recruited. Both protocol one and two were able to discriminate between groups at statistically significant levels.
Answer: Construct validity has been established by showing that error analysis is able to distinguish surgeons with varying levels of experience.

A: Is the surgical error examination a novel method for objective technical knowledge assessment?
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Q: Context: To investigate the effects of transforming growth factor beta1 (TGF-beta1) on dendritic cells (DC).', 'Murine bone marrow cells were cultured with different cytokine combinations to develop immature DC (imDC, GM-CSF only) and TGFbeta-DC (GM-CSF + TGF-beta1), and their responses to lipopolysaccharide (LPS) stimulation were observed. The cell ultrastructure was observed by transmission electron microscopy and their phenotypes were assessed by flow cytometry (FCM). The allogeneic stimulating capacity of DC was assayed by mixed lymphocyte reaction (MLR) with BrdU incorporation. IL-12p70 protein was detected by ELISA and the expressions of Toll-like receptor 4 (TLR4) on DCs were analyzed with semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR).', 'Compared to imDC, the TGFbeta-DC had no significant alterations in ultrastructure after LPS stimulation. The expressions of CD80, CD86 were lower on TGFbeta-DC than on imDC [(4.14 +/- 0.95)% vs (13.90 +/- 7.22)%; (8.60 +/- 0.75)% vs (20.63 +/- 5.03)%, P < 0.05, both]. The TGFbeta-DC kept their immature morphology after LPS stimulation, but the expressions of I-Ab and CD80 were slightly increased. After 96 h MLR, TGFbeta-DC had weaker stimulating capacity than imDC did, especially when DC/T cells ratios were 1:4 and 1:1 (P < 0.05, both). TGFbeta-DC showed impaired IL-12p70 production and down-regulation of TLR4 expression.
Answer: TGF-beta1 can inhibit the expression of co-stimulatory molecules on DC. The TGFbeta-DC is resistant to maturation stimulus (LPS) and might be linked with TLR4 down-regulation.

A:
Do [ Effects of transforming growth factor beta1 on dendritic cells function ]?
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