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INTRODUCTIONThis case report outlines the investigation and management of a young patient presenting with left iliac fossa pain and sepsis. A CT was performed which was initially reported as not showing a perforation, however closer analysis provided evidence of subcutaneous emphysema in the anterior abdominal wall. This evidence justified urgent operative intervention. We review the evidence with regard to this presentation.PRESENTATION OF CASEA previously fit 24-year-old male presented with left iliac fossa pain and features of sepsis. A CT provided subtle but distinctive evidence of retroperitoneal perforation secondary to diverticulitis, in the form of surgical emphysema in the anterior abdominal wall. In view of this, urgent operation was considered justified on suspicion of visceral perforation. A diverticular perforation was confirmed intra-operatively, and a sigmoid colectomy with primary anastomosis was performed, together with a covering ileostomy. The patient made a good post-operative recovery.DISCUSSIONDiverticular disease and its complications are becoming more common in a younger age group, in whom perforation may present late or may not be suspected. In this context special attention must be paid to any radiological evidence of perforation.CONCLUSIONSurgical emphysema in the abdominal wall is an indicator of retroperitoneal perforation, and its presence should be excluded before the possibility of perforation is dismissed. This may be of especial value in younger age groups amongst whom perforation may be less clinically obvious.  相似文献   
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BACKGROUND: Although guidelines recommend anti-inflammatory therapy for persistent asthma, recent studies suggest that 25% to 35% of patients with asthma may not improve lung function with inhaled corticosteroids. OBJECTIVE: To evaluate potential biomarkers of predicting short-term (6-week) response to inhaled corticosteroid with subsequent evaluation of responders and nonresponders to asthma control over a longer interval (16 additional weeks). METHODS: Eighty-three subjects with asthma off steroid were enrolled in this multicenter study. Biomarkers and asthma characteristics were evaluated as predictors of inhaled corticosteroid response over a 6-week trial for changes in FEV(1) and methacholine PC(20). After this, an additional 4-month trial evaluated asthma control. RESULTS: Although multiple baseline predictors had significant correlations with improvements for short-term inhaled steroid success, the only strong correlations (r >or= +/- 0.6) were albuterol reversibility (r = 0.83; P < .001), FEV(1)/forced vital capacity (r = -0.75; P < .001), and FEV(1) % predicted (r = -0.71; P < .001). Dividing the subjects in the short-term inhaled steroid trial into responders (>5% FEV(1) improvement) and nonresponders (相似文献   
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Blinding is a critical component in randomized clinical trials along with treatment effect estimation and comparisons between the treatments. Various methods have been proposed for the statistical analyses of blinding-related data, but there is little guidance for determining the sample size for this type of data, especially if blinding assessment is done in pilot studies. In this paper, we try to fill this gap and provide simple methods to address sample size calculations for a “new” study with different research questions and scenarios. The proposed methods are framed in terms of estimation/precision or statistical testing to allow investigators to choose the best suited method for their goals. We illustrate the methods using worked examples with real data.  相似文献   
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Evidence from several studies suggests that the progressive degeneration of dopaminergic (DA) neurones of the substantia nigra pars compacta (SNc) in Parkinson's disease (PD) may in part be due to excessive release of glutamate from subthalamic projections onto nigral DA neurones. Previous in vitro studies have demonstrated that selective activation of Group III metabotropic glutamate receptors (mGluR) negatively modulates excitatory transmission in the SNc and is neuroprotective against glutamate-mediated toxicity. Consistent with this, we have reported preliminary data indicating that the selective group III mGluR agonist l-(+)-2-amino-4-phosphonobutyric acid (l-AP4) can also protect the nigrostriatal system against 6-hydroxydopamine (6-OHDA) toxicity in vivo. We have now extended these preliminary studies in this model and report here that both acute and subchronic intranigral injections of l-AP4 provide significant protection of the nigrostriatal system against 6-OHDA toxicity. This neuroprotection displays a bell-shaped profile with a clear concentration-dependent relationship. In contrast, when administered to animals 7 days post-6-OHDA lesioning, l-AP4 significantly protects the functionality but not the integrity of the nigrostriatal system. We further demonstrate that neuroprotection by l-AP4 in vivo is reversed by coadministration of the selective Group III mGluR antagonist (RS)-alpha-methylserine-O-phosphate, confirming a receptor-mediated mechanism of action. These data provide further compelling evidence that selective activation of Group III mGluR is neuroprotective in an in vivo experimental model of PD, a finding that may have important implications for the future treatment of this disease.  相似文献   
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OBJECTIVES: To examine the effects of inhaled NONOates in patients with acute respiratory distress syndrome (ARDS). DESIGN: Case-series, phase I clinical trial. SETTING: A multidisciplinary intensive care unit in a tertiary teaching hospital. PATIENTS: Five consecutive patients with ARDS (men; age range, 47-76 years). MEASUREMENTS: DETA/NO (150 micromol) was aerosolized into the lungs of patients on mechanical ventilation via the endotracheal tube over 20 minutes. Hemodynamic parameters were measured and blood samples were taken before, during, and after inhalation. RESULTS: Compared to baseline values, pulmonary vascular resistance decreased until the end of the study period (180 minutes) while intrapulmonary shunting decreased significantly up to 45 min after DETA/NO aerosol administration. Inhaled DETA/NO had no effect on the systemic circulation (systemic blood pressure or cardiac output). CONCLUSIONS: Inhaled DETA/NO is a selective pulmonary vasodilator in patients with ARDS. However, a larger number of patients is required to confirm the findings of this pilot study.  相似文献   
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World Journal of Surgery - Traditional chemotherapy agents adversely affect wound healing and need to be held prior to or after surgery. Immune checkpoint inhibitors (ICIs) and targeted agents are...  相似文献   
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