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Introduction and objectiveTranscatheter aortic valve implantation (TAVI) is an alternative therapeutic approach to patients not considered suitable for surgical aortic valve replacement (SAVR) due to their high operative risk. We sought to assess the impact of TAVI on the profile and operative results of patients with severe aortic stenosis undergoing SAVR.MethodsA total of 214 patients were included, of whom 103 consecutive patients underwent isolated SAVR in 2005 and 111 in 2009. Patients’ demographic and operative data were collected retrospectively. Operative and one-year mortality and morbidity were analyzed.ResultsPatients’ mean age was 70 years, and 56% were female. Following the introduction of a TAVI program, patients undergoing conventional surgery were older, with more comorbidities. Overall 30-day and one-year mortality were 2.8% and 7.0%, respectively. After the introduction of TAVI, the observed mortality rate for SAVR decreased, but not significantly (operative mortality: 3.9% before TAVI vs. 1.8% after TAVI, p=NS; one-year mortality: 10% vs. 4.5%, p=NS). Striking differences were observed in morbidity (operative morbidity: 23.3% before TAVI vs. 13.5% after TAVI, p=0.047, and one-year morbidity: 20.4% vs. 9.9%, p=0.032).ConclusionsSince the introduction of a TAVI program at our center, the number of patients undergoing SAVR has increased, with a slight rise in surgical risk, but without worsening the final operative results. The implementation of a TAVI program has thus had a positive impact on the volume of procedures, patient selection and outcomes in SAVR.  相似文献   
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J Oral Pathol Med (2010) 39 : 435–439 Background: It is diagnostically difficult to differentiate plasmablastic lymphomas (PBLs) from plasma cell neoplasms with plasmablastic differentiation. Plasmablastic lymphomas are currently classified as ‘PBL of the oral mucosa’ and ‘PBL with plasmacytic differentiation’. Methods: Forty‐five cases of PBL were retrieved from the Departments of Oral Pathology of the Universities of Pretoria and Limpopo, South Africa. Clinical features and HIV status were recorded and each case was classified as ‘PBL of the oral mucosa type’ or as ‘PBL with plasmacytic differentiation’. Immunohistochemistry included: CD45, CD3, CD20, CD79a, CD38, CD138, MUM1, Ki‐67 and kappa and lambda light chains. Positivity was recorded based on the percentage of positive staining cells as focal (5–20%); intermediate (20–70%) or diffuse (>70%). In situ hybridization was performed for Epstein–Barr virus (EBV) and HHV‐8. Results were recorded as positive or negative. Results: All cases showed some degree of plasmacytic differentiation. All were negative for CD20 with reactive T cells detected with CD3. Diffuse and strong positive staining was found with Ki‐67 and MUM1, but variable immunoreactivity was found with CD79a, CD45, CD38 and CD138. Twenty cases (47%) showed light chain restriction. Epstein–Barr virus was detected in 44/45 cases and HHV‐8 in none. Conclusions: The morphological classification of PBLs is not valid as all cases showed some degree of plasmacytic differentiation. We propose that PBLs with light chain restriction be reclassified as ‘plasmablastic extramedullary plasmacytomas’ and managed accordingly. The rest represents true PBLs. The true nature of these neoplasms as an entity should be further investigated with molecular and genetic studies.  相似文献   
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Trans-fatty acids have been implicated as a risk factor for cardiovascular disease and diabetes. In addition, a polymorphism at codon 54 (Ala54Thr) in the fatty acid-binding protein 2 (FABP2) gene has been suggested to modify an interaction between dietary fat and insulin sensitivity. We examined the postprandial metabolic profiles after meals enriched with C18:1trans- relative to a similar meal with C18:1cis-fatty acid in individuals who were either FABP2 Ala54 homozygotes or Thr54 carriers. Moderately overweight men and women ate 2 breakfast test meals, separated by 1 week, each providing 40% of their daily energy requirement and containing 50% of energy as fat. In one meal, 10% of energy was from C18:1trans, and in the other meal, the C18:1trans was replaced with C18:1cis. Metabolic parameters were assessed during an 8-hour period. Insulin and C-peptide levels increased more after the C18:1trans meal, and this was associated with a greater fall in free fatty acids. Postprandial glucose levels and oxidation of fatty acids and carbohydrate were not different between the 2 test meals. The Thr54 allele for FABP2 increased the rise in postprandial glucose but not triacylglycerols. Fractional triacylglycerol synthetic rates were higher after consumption of the C18:1trans meal relative to the C18:1cis meal only in Thr54 carriers. These data show that a single meal enriched with C18:1trans-fatty acids can significantly increase insulin resistance, and that in the presence of the FABP2 Thr54 allele, may contribute to increased partitioning of glucose to triacylglycerols and insulin resistance.  相似文献   
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