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.
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Context: Brassica napus (AACC) is self-compatible, although its ancestor species Brassica rapa (AA) and Brassica oleracea (CC) are self-incompatible. Most B.napus accessions have dominant self-compatibility (SC) resulting from an insertion of 3.6 kb in the promoter region of BnSCR-1 on the A genome, while recessive SC in B.napus has rarely been observed. Expression and cloning of SRK and SCR genes and genetic analysis were carried out to dissect bases of recessive SC in B.napus.', 'Eleven accessions were screened to identify stable recessive SC and had the S genotype BnS-7 on the A genome and BnS-6 on the C genome similarly to BrS-29 and BoS-15, respectively. In eight SC accessions, BnSCR-7 and BnSCR-6 were nearly undetectable and harbored no structural mutations in the promoters, while SRK genes were expressed at normal levels and contained intact CDS, with the exception of BnSRK-7 in line C32. SRK and SCR genes were expressed normally but their CDSs had no mutations in three SC accessions. In self-incompatible S-1300 and 11 F1 hybrids, SRK genes and BnSCR-1300 transcripts were present at high levels, while expression of the BnSCR-7 and BnSCR-6 were absent. Plants of S genotype S1300S1300 were completely SI, while SI phenotypes of SBnS-7SBnS-7 and S1300SBnS-7 plants were segregated in BC1 and F2 populations.
Answer: The recessive SC in eight accessions is caused by the loss of function of BnSCR-7 and BnSCR-6 in pollen. Translational repression contributes to the recessive SC in three accessions, whose SRK and SCR genes were expressed normally and had identical CDSs to BrS-29 or BoS-15. SI in 11 F1 hybrids relies on the expression of BnSCR-1300 rather than SRK genes. Other factor(s) independent of the S locus are involved in recessive SC. Therefore, diverse causes underlie recessive SC in B. napus, yielding insight into these complex mechanisms.
answer:
Do gene expression and genetic analysis reveal diverse causes of recessive self-compatibility in Brassica napus L?

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Context: Ischemic mitral regurgitation (MR) often persists after restrictive mitral valve annuloplasty, in which case it is associated with worse clinical outcomes. The goal of the present study was to determine whether persistence of MR and/or clinical outcome could be predicted from preoperative analysis of mitral valve configuration.', 'In 51 consecutive patients undergoing restrictive annuloplasty for ischemic MR, posterior leaflet (PL) angle, anterior leaflet angle, coaptation distance, and tenting area were quantified by echocardiography before surgery (6+/-3 days), and MR severity was assessed before and early after surgery (9+/-4 days). Postoperatively, persistence of mild to moderate MR (vena contracta > 3 mm) was observed in 11 (22%) of the patients. The best predictor of postoperative persistence of MR was a PL angle > or = 45 degrees (sensitivity 100%, specificity 97%, positive predictive value 92%, negative predictive value 100%). Patients with persistent MR had markedly lower 3-year event-free survival (26+/-20%) compared with those with nonpersistent MR (75+/-12%, P=0.01). Preoperative presence of a PL angle > or = 45 degrees also was associated with a markedly lower 3-year event-free survival (22+/-17% versus 76+/-12%; P<0.001).
Answer: In patients undergoing restrictive annuloplasty for ischemic MR, persistence of MR and 3-year event-free survival can accurately be predicted by preoperative analysis of mitral valve configuration. Patients with a PL angle > or = 45 degrees (ie, with high PL restriction) should thus be considered poor candidates for this procedure, and concomitant or alternative procedures should be contemplated.
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Does preoperative posterior leaflet angle accurately predict outcome after restrictive mitral valve annuloplasty for ischemic mitral regurgitation?

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Context: Due to increased use of imaging techniques, adrenal incidentalomas are frequently detected. The majority are non-hyperfunctioning adrenocortical tumors. We have previously shown that expression of the gene CYP17, coding for the enzyme in the cortisol pathway, correlates with cortisol release from adrenocortical tumors in vitro. The aim of this study was to compare clinical data with mRNA expression of CYP17 and CYP11B1 in adrenocortical tumors from patients with and without Cushing's syndrome and to identify adrenal tumors that may cause subclinical Cushing's syndrome.", 'A retrospective study of 34 patients undergoing adrenalectomy due to an adrenal tumor.', 'Clinical data were collected. In the adrenal gland the mRNA expression of the genes CYP17 and CYP11B1 was studied with in situ hybridisation technique.', "The median ratio of CYP17/CYP11B1 expression in tumors from patients with Cushing's syndrome was significantly higher than the median ratio in the non-hyperfunctioning tumors. Tumors from 2 patients with subclinical Cushing's syndrome had ratios within the upper range for non-hyperfunctioning tumors.
Answer: The ratio between the expression of the genes CYP17 and CYP11B1 in tumors from patients with Cushing's syndrome is significantly higher than in the non-hyperfunctioning tumors. This indicates that 17alpha-hydroxylase is a major determinant of cortisol overproduction. The patients with subclinical Cushing's syndrome in this study are too few to draw any firm conclusions although the results suggest that subclinical Cushing's syndrome may be identified post-operatively with this method.
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Does increased ratio of mRNA expression of the genes CYP17 and CYP11B1 indicate autonomous cortisol production in adrenocortical tumors?