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OBJECTIVE: The surgical treatment of epistaxis associated with hereditary hemorrhagic telangiectasia (HHT) is varied. Laser therapy is often inadequate for larger complex lesions. This study sought to determine if bipolar cautery can be effectively and safely used in treating HHT-associated epistaxis. STUDY DESIGN AND SETTING: Records from all patients with HHT treated surgically over 8 years were reviewed retrospectively. Outcomes or complications were noted in the clinic on follow-up evaluation. RESULTS: Twenty-seven patients with HHT who underwent surgical treatment of epistaxis were evaluated; 18 were treated with bipolar cautery. Forty-two separate bipolar treatments were performed. No new septal perforations or synechiae were noted. Twenty-two of 42 treatments were coupled with ancillary laser treatments. The bipolar was also used as the sole technique in 20 procedures. CONCLUSION: Bipolar electrocautery is a safe and effective tool for the intraoperative control of HHT-related epistaxis. SIGNIFICANCE: Bipolar electrocautery may be used as an adjunct to laser techniques or as a stand-alone technique. EBM RATING: C-4.  相似文献   
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The calcar femorale in cemented stem fixation in total hip arthroplasty   总被引:2,自引:0,他引:2  
The calcar femorale is a vertical plate of bone lying deep to the lesser trochanter and is formed as a result of traction of the iliopsoas which separates the femoral cortex into two distinct layers, the calcar femorale and the medial femoral cortex. They fuse together proximally to form the medial femoral neck. A stem placed centrally will abut against the calcar femorale with little or no space for cement. Clearing of the calcar will offer space for a cement layer, which will support the stem proximally on the posterior aspect. We compared two consecutive groups of Charnley low-friction arthroplasties, with and without clearing of the calcar. In 330 patients who had an arthroplasty without clearing the calcar, there were ten revisions for aseptic loosening of the stem and six other stems were considered 'definitely loose', giving a rate of failure of 4.8%. In 111 patients in whom the calcar was cleared there was only one revision for aseptic loosening and no stems were classed as 'definitely loose', giving a rate of failure of 0.9%. Survivorship analysis has again shown the need for long-term follow-up; the differences became clear after ten years but because of the relatively small numbers, statistical analysis is not yet applicable. We now clear the calcar femorale routinely and advocate optimal access to the medullary canal and insertion of the stem in the area of the piriform fossa.  相似文献   
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This paper examined whether international variations in absolute and relative gender differences in mortality are related to the overall mortality rates, and whether the international variation in gender gap in mortality can in part be explained by smoking. I used data on mortality from all causes in 32 European countries published by the World Health Organisation, and indirect estimates of mortality attributable to smoking in the age band 35–69 years by Peto et al. The main analyses were restricted to the age band 35–69 years but results for mortality at all ages were virtually identical. The overall mortality rates (both sexes combined) were strongly related to absolute gender differences (r = 0.91) but only weakly to relative differences (r = 0.35). The gender gap was larger in eastern than in western Europe for rate differences (1005 vs. 530 per 100,000, respectively), but it was similar for rate ratios (2.3 vs. 2.1, respectively). Both absolute and relative gender differences in mortality were strongly related to the difference between men and women in the proportion of all deaths attributed to tobacco (partial correlations, after controlling for the overall death rates, were 0.59 and 0.66, respectively). Excluding tobacco-related deaths attenuated the associations between the overall mortality rates with absolute differences (r = 0.70) and reduced the difference in the absolute gender gap between eastern and western Europe. More importantly, excluding tobacco-related deaths eliminated entirely the association with relative differences (r = –0.15) as well as any suggestion that the relative gender gap is larger in eastern than in western Europe. These results show that tobacco plays an important role in generating international differences in the size of gender gap in mortality. The much discussed association between the overall life expectancy and the gender gap in life expectancy is a numerical product of absolute death rates (differences in life expectancy are driven by differences in rates). The association of overall mortality with male/female mortality ratios is much weaker.  相似文献   
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CONTEXT: Evidence for an association between alcohol consumption and activity of the hypothalamic-pituitary-adrenal (HPA) axis is inconclusive. OBJECTIVE: Our objective was to assess the relationship between indices of alcohol consumption and salivary cortisol concentration. DESIGN: This was a cross-sectional study of alcohol consumption and cortisol secretion from phase 7 (2002-2004) of the Whitehall II study. SETTING: An occupational cohort originally recruited in 1985-1987 was included in the study. PARTICIPANTS: A total of 2693 men and 977 women had information on cortisol levels and alcohol consumption. OUTCOME MEASURES: Saliva samples were taken on waking, waking+0.5, 2.5, 8, and 12 h, and bedtime for the assessment of cortisol. RESULTS: In men there was a positive association between cortisol and units of alcohol intake per week (3% increase in cortisol per unit of alcohol consumed; P=0.010). The slope of cortisol decline over the day in heavy drinkers was reduced (heavy drinkers beta=-0.155, moderate drinkers beta=-0.151), indicating reduced control of the HPA axis in heavy drinkers. In women the cortisol awakening response was greater in heavy drinkers 14.15 nmol/liter (9.12-19.17) compared with moderate drinkers 8.69 nmol/liter (7.72-9.67) (P=0.037). CONCLUSIONS: This study suggests that alcohol consumption is associated with activation of the HPA axis. These results are not due to alcohol consumption on the day, suggesting chronic changes of the HPA axis in heavy drinking groups.  相似文献   
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HLA-DO (H2-O in mice) is an intracellular non-classical MHC class II molecule (MHCII). It forms a stable complex with HLA-DM (H2-M in mice) and shapes the MHC class II-associated peptide repertoire. Here, we tested the impact of HLA-DO and H2-O on the binding of superantigens (SAgs), which has been shown previously to be sensitive to the structural nature of the class II-bound peptides. We found that the binding of staphylococcal enterotoxin (SE) A and B, as well as toxic shock syndrome toxin 1 (TSST-1), was similar on the HLA-DO+ human B cell lines 721.45 and its HLA-DO counterpart. However, overexpressing HLA-DO in MHC class II+ HeLa cells (HeLa-CIITA-DO) improved binding of SEA and TSST-1. Accordingly, knocking down HLA-DO expression using specific siRNAs decreased SEA and TSST-1 binding. We tested directly the impact of the class II-associated invariant chain peptide (CLIP), which dissociation from MHC class II molecules is inhibited by overexpressed HLA-DO. Loading of synthetic CLIP on HLA-DR+ cells increased SEA and TSST-1 binding. Accordingly, knocking down HLA-DM had a similar effect. In mice, H2-O deficiency had no impact on SAgs binding to isolated splenocytes. Altogether, our results demonstrate that the sensitivity of SAgs to the MHCII–associated peptide has physiological basis and that the effect of HLA-DO on SEA and TSST-1 is mediated through the inhibition of CLIP release.  相似文献   
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A systematic review of the literature was undertaken to evaluate the outcomes and complications following proximal femoral arthroplasty for primary or metastatic tumors affecting the proximal femur. Six hundred sixty-eight patients were available for review. The length of resection ranged from 92 to 212 mm. Limb salvage rate reached over 90%. At 5 years the implant survival rate was 84% and at 10 years, it was 70%. The overall revision rate was 11.1%. Prevalence of venous thrombo-embolic (VTE) events was 8.5%, dislocation rate was 5.8%, infection was 5.2%, local tumor reoccurrence was 4.7%, perioperative mortality was 1.5%, and periprosthetic fracture was 0.6%. Where it was provided the Musculoskeletal Tumour Score was 70.8%. The implants tend to outlive patients with metastatic disease and high-grade localized disease, providing them with a relatively pain-free limb with good mobility and quality of life.  相似文献   
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