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71.

Background

Differences in outcomes have previously been reported between urban and rural settings across a multitude of chronic diseases. Whether these discrepancies have changed over time, and how sex may influence these findings is unknown for patients with ambulatory heart failure (HF). We examined the temporal incidence and mortality trends by geography in these patients.

Methods and Results

We conducted a retrospective cohort study of 36,175 eastern Ontario residents who were diagnosed with HF in an outpatient setting from 1994 to 2013. The primary outcome was 1-year mortality. We examined temporal changes in mortality risk factors with the use of multivariable Cox proportional hazard models. The incidence of HF decreased in women and men across both rural and urban settings. Age-standardized mortality rates also decreased over time in both sexes but remained greater in rural men compared with rural women.

Conclusions

The incidence of HF in the ambulatory setting was greater for men than women and greater in rural than urban areas, but mortality rates remained higher in rural men compared with rural women. Further research should focus on ways to reduce this gap in the outcomes of men and women with HF.  相似文献   
72.
To investigate the role of primary T cell repertoire selection in the immunopathogenesis of autoimmune diseases, pure thymic epithelium (TE) from nonobese diabetic (NOD) embryos was grafted into non autoimmune prone newborn C57BL/6 athymic mice. The results show that NOD TE selects host T cell repertoires that establish autoimmunity in otherwise nondiabetic animals. Thus, such chimeras regularly show CD4 and CD8 T cell-mediated insulitis and sialitis, in contrast with syngeneic or allogeneic chimeras produced with TE from nonautoimmune strains. This is the first demonstration that autoimmunity to pancreatic β cells and salivary glands can be established by the sole alteration of the thymic environment involved in T cell selection, regardless of the nature and presentation of both major histocompatibility complex and tissue-specific antigens on the target organ. These data indicate that T cell repertoire selection by the NOD thymic epithelium is sufficient to induce specific autoimmune characteristics in the context of an otherwise normal host.  相似文献   
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74.
Objective:To assess hyperacusis after stapedotomy and its possible influencing factors.Study design:Prospective,interventional,and longitudinal study.Setting:A tertiary referral center.Patients:Fifty consecutive patients(35 females,mean age=46.8 years).Intervention:All patients underwent stapedotomy.The validated Portuguese version of the“Hyperacusis Questionnaire”(HQ)was administered before and two weeks and one month after surgery.Results:No hyperacusis was reported by any patient before surgery.At two weeks after surgery,all patients experienced hyperacusis,with a mean HQ at 16.88±6.54(range 4e25).One month after surgery,hyperacusis had already resolved in most patients.Gender,preoperative presentation or surgeon had no influence on HQ scores(p>0.05).Patients with previous contralateral stapedotomy showed lower HQ scores(p=0.001).Audiological parameters improvement measured at one month after surgery(PTA,SRT and contralateral SRT)were associated with HQ higher scores.Conclusion:This study confirms that hyperacusis is a common complaint after stapedotomy that usually resolves in one month after surgery.The HQ highest scores were registered among patients with the highest audiological gain after surgery.This suggests that hyperacusis may be a positive prognostic factor for audiological success after stapedotomy.  相似文献   
75.

Background

Self-expandable metal stents (SEMSs) can be used for palliation of combined malignant biliary and duodenal obstructions. However, the results of the concomitant stent placement for the duration of the patients’ lives, as well as the need for and efficacy of endoscopic revision, are unclear.

Aim

This study evaluated the clinical effectiveness of SEMS placement for combined biliary and duodenal obstructions throughout the patients’ lives and the need for endoscopic revision.

Methods

This study is a retrospective multicenter study of 50 consecutive patients who underwent simultaneous or sequential SEMS placement for malignant biliary and duodenal obstructions. The data were collected to analyze the sustained relief of obstructive symptoms until the patients’ death and the efficacy of endoscopic revision, as well as stent patency, adverse events, survival and prognostic factors for stent patency.

Results

Technical and immediate clinical success was achieved in all of the patients. Duodenal stricture occurred before the papilla in 35 patients (70 %), involved the papilla in 11 patients (22 %) and was observed distal to the papilla in four patients (8 %). Initial biliary stenting was performed endoscopically in 42 patients (84 %) and percutaneously in eight patients. After combined stenting, 30 patients (60 %) required no additional intervention until the time of their death. The remaining 20 patients were successfully treated using endoscopic stent reinsertion: nine patients needed biliary revision, three patients needed duodenal restenting and eight patients needed both biliary and duodenal reinsertion. The median duodenal stent patency and median biliary stent patency were 34 and 27 weeks, respectively. The median survival after combined stent placement was 18 weeks. A Cox multivariate analysis showed that duodenal stent obstruction after combined stenting was a risk factor for biliary stent obstruction (hazard ratio 6.85; 95 % confidence interval 1.43–198.98; P = 0.025).

Conclusions

Endoscopic bilio-duodenal bypass is clinically effective, and the majority of the patients need no additional intervention until their death. Endoscopic revision is feasible and has a high success rate.  相似文献   
76.
77.
Anti-N-methyl-d-aspartate receptor (anti-NMDAR) encephalitis is an auto-immune and paraneoplastic encephalitis which generally affects young adults. It is a multistage illness, with prominent extrapyramidal, neuropsychiatric and autonomic symptoms. The syndrome is frequently associated with an ovarian teratoma. Recently, it has become evident that anti-NMDAR encephalitis is more common in children and adolescents than was previously believed. Prognostic factors that determine a good outcome are presence of a tumour, prompt treatment and no need for admission to an intensive care unit. Increased awareness among paediatricians of this potentially life-threatening disease is important because early recognition and treatment will improve the patients’ chances of a good clinical outcome. In this case report, we describe a 9-year-old girl with behavioural changes and severe extrapyramidal symptoms due to anti-NMDAR encephalitis associated with an ovarian teratoma. She was treated with a variety of immunomodulating therapies and made a slow, but good recovery.  相似文献   
78.
79.
Grafts of thymic epithelium (TE) rudiments restore T cell development and function in allogeneic athymic mice. These TE chimeras are specifically tolerant to grafts of peripheral tissues (e.g. skin and heart) from the TE donor strain, although they harbor peripheral immunocompetent T cells capable of rejecting those grafts. Initial analysis has shown that TE chimeras also harbor TE-selected CD4 T lymphocytes that inhibit graft rejection by tissue-reactive T cells in immunocompetent recipients. Peripheral tolerance in TE chimeras is thus maintained by dominant mechanisms dependent on regulatory CD4 T lymphocytes. Here we show that TE-selected regulatory T cells recruit nontolerant tissue-reactive CD4 and CD8 T cells to express similar regulatory functions. Only recent thymic emigrants, but not peripheral resident mature T cells are susceptible to this process of functional education, which also requires exposure to specific antigens and occurs entirely in the periphery. We propose that these mechanisms play a major role in establishing and maintaining natural self tolerance to tissue-specific antigens.  相似文献   
80.
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