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71.
OBJECTIVES: This study was designed to evaluate whether the destruction of the World Trade Center (WTC) on September 11, 2001 (9/11), led to an increased frequency of ventricular arrhythmias among patients fitted with an implantable cardioverter-defibrillator (ICD). BACKGROUND: The WTC attack induced psychological distress. Because ICDs store all serious arrhythmias for months, the attack provided a unique opportunity to compare pre- and post-9/11 frequencies of potentially lethal arrhythmias among ICD patients. METHODS: Two hundred consecutive ICD patients who presented for regularly scheduled follow-up to six affiliated clinics were recruited into this observational study. The electrograms stored in the ICDs for the three months before 9/11 and 13 months thereafter were scrutinized in a blinded manner (relative to date) for all ventricular tachyarrhythmias (tachycardia or fibrillation) triggering ICD therapy. RESULTS: The frequency of tachyarrhythmias increased significantly for the 30 days post-9/11 (p = 0.004) relative to all other months between May 2001 and October 2002. In the 30 days post-9/11, 16 patients (8%) demonstrated tachyarrhythmias, compared with only seven (3.5%) in the preceding 30 days, representing a 2.3-fold increase in risk (95% confidence interval 1.1 to 4.9; p = 0.03). The first arrhythmic event did not occur for three days following 9/11, with events accumulating in a progressive non-clustered pattern. CONCLUSIONS: Ventricular arrhythmias increased by more than twofold among ICD patients following the WTC attack. The delay in onset and the non-clustered pattern of these events differ sharply from effects following other disasters, suggesting that subacute stress may have served to promote this arrhythmogenesis.  相似文献   
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BackgroundFunctional tricuspid regurgitation (TR) is a frequent finding in echocardiography. Despite general consent that right ventricular (RV) dysfunction impacts outcome of patients with TR, it is still unknown which echocardiographic parameters most accurately reflect prognosis. In this study we aimed to evaluate the prevalence of RV dysfunction and its prognostic value in patients with TR.MethodsData from 1089 consecutive patients were analysed. Tricuspid annular plane systolic excursion (TAPSE), fractional area change, and right ventricular free wall longitudinal strain (RV strain) were used to define RV dysfunction. Patients were followed for 2-year all-cause mortality. For prediction of survival, reclassification and C statistics of RV functional parameters using TR grade as reference model were performed.ResultsAmong the patients studied, 13.9% showed no TR, 61.2% had mild TR, 19.6% had moderate TR, and 5.3% had severe TR. The TR grade was associated with increased mortality (log rank, P < 0.001). Impaired RV strain and TAPSE were independent predictors for mortality (RV: hazard ratio [HR], 1.130; 95% confidence interval [CI], 1.099-1.160; P < 0.001; TAPSE: HR, 1.131; 95% CI, 1.085-1.175; P < 0.001). Both RV strain and TAPSE improved the reference model for survival prediction (RV: integrated discrimination improvement [IDI], 0.184; 95% CI, 0.146-0.221; P < 0.001; TAPSE: IDI, 0.057; 95% CI, 0.037-0.077; P < 0.001).ConclusionsEchocardiographic evaluation of RV function appears to useful for patients with TR. Assessment of RV strain provides additional value for prediction of 2-year mortality.  相似文献   
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Following gastrectomy for locally advanced adenocarcinomas, three patients developed microangiopathic hemolytic anemia and renal failure shortly after completing courses of adjuvant chemotherapy with mitomycin and 5-FU. These complications progressed despite cessation of chemotherapy, and all three patients died of noncardiogenic pulmonary edema precipitated in two cases by blood transfusions. At autopsy, two patients had no residual carcinoma and all had a diffuse microangiopathy involving mainly the kidneys and lungs. There was intimal hyperplasia of many arterioles sometimes associated with complete occlusion of the lumen, prominent nuclear atypia in many capillary cells, and numerous capillary fibrin thrombi. Direct immunofluorescence studies revealed extensive fibrinogen-fibrin deposits in the vascular lesions. Chemotherapy-induced microangiopathic hemolytic anemia and renal failure may predispose patients to fatal episodes of noncardiogenic pulmonary edema that can be triggered by blood transfusions.  相似文献   
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Objectives

The aim of this study was categorizing the microbial flora and susceptibility to antibiotics and to clarify to which degree the empiric administered antibiotics are suitable for therapy.

Materials and methods

A 3.5-year retrospective study evaluated hospital records of 206 patients who suffered from head and neck infections of odontogenic origin. All patients underwent surgical incision and drainage and received intravenous antibiotics and inpatient treatment. The specimens were obtained by performing a swab.

Results

Two hundred six patients were included with 251 strains isolated (1.22 per patient). One hundred eight strains showed antibiotic resistance. Eighty-seven patients showed at least one bacterial strain that showed antibiotic resistance (42.2%). The most frequent isolated bacteria were Streptococcus spp. (n = 116), with a high rate of antibiotic resistance (50.8%). We investigated 205 cases of antibiotic resistance in 87 subjects. Nine bacterial strains showed no susceptibility to unacid (4.3%) and 36 strains to clindamycin (17.5%).

Conclusion

Antibiotic resistance against clindamycin was rather high. The distribution of the afflicted spaces and isolated bacteria was alike recent findings. It is mandatory to understand that immediate surgical treatment in terms of incision and drainage is the basis in abscess treatment. Antibiotic treatment is adjunct therapy.

Clinical relevance

Streptococcus species were the most frequently identified bacteria presenting antibiotic resistance in more than 50%. Increased resistant rates for clindamycin require reconsiderations regarding an empiric antibiotic treatment.

  相似文献   
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Clinical Oral Investigations - The aim of this study was to assess the influence of transgingival compared with submerged healing on peri-implant bone maintenance around a novel, fully tapered...  相似文献   
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BackgroundAtopic dermatitis (AD) is a chronic inflammatory skin disease that affects 20% of children worldwide. Environmental factors including weather and air pollutants have been shown to be associated with AD symptoms. However, the time‐dependent nature of such a relationship has not been adequately investigated. This paper aims to assess whether real‐time data on weather and air pollutants can make short‐term prediction of AD severity scores.MethodsUsing longitudinal data from a published panel study of 177 paediatric patients followed up daily for 17 months, we developed a statistical machine learning model to predict daily AD severity scores for individual study participants. Exposures consisted of daily meteorological variables and concentrations of air pollutants, and outcomes were daily recordings of scores for six AD signs. We developed a mixed‐effect autoregressive ordinal logistic regression model, validated it in a forward‐chaining setting and evaluated the effects of the environmental factors on the predictive performance.ResultsOur model successfully made daily prediction of the AD severity scores, and the predictive performance was not improved by the addition of measured environmental factors. Potential short‐term influence of environmental exposures on daily AD severity scores was outweighed by the underlying persistence of preceding scores.ConclusionsOur data does not offer enough evidence to support a claim that weather or air pollutants can make short‐term prediction of AD signs. Inferences about the magnitude of the effect of environmental factors on AD severity scores require consideration of their time‐dependent dynamic nature.  相似文献   
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