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1.

Background

In the emergency department, rib fractures are a common finding in patients who sustain chest trauma. Rib fractures may be a sign of significant, underlying pathology, especially in the elderly patients where rib fractures are associated with significant morbidity and mortality. To date, no studies have evaluated the ability of ultrasound to detect rib fractures using cadaver models and subsequently use this model as a teaching tool.

Objectives

The purpose of this study was to determine if it is possible to generate rib fractures on cadaver models which could be accurately identified using ultrasound.

Methods

This was a cross-sectional study performed during one session at a cadaver lab. A single hemithorax from four adult cadavers were used as models. Single rib fractures on each of rib five through eight were created. Four subjects, blinded to the normal versus fractured ribs, were asked to identify the presence of a fracture on each rib.

Results

A total of 8 of 16 potential ribs had fractured induced by study staff. Mean accuracy was 55% for all subjects. The overall sensitivity and specificity for detecting rib fractures was 50% (CI: 31.89–68.11) and 59.38% (CI: 35.69–73.55) respectively. The overall PPV and NPV was 55.17% and 54.29% respectively.

Conclusions

In this pilot study, subjects were not able to detect induced rib fractures using ultrasound on cadaver models. The use of this model as a teaching tool in the detection of rib fractures requires further investigation.  相似文献   
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PURPOSE: Epilepsies in children are complex diseases. Guidelines are needed on the appropriate use of newer versus older anti-epileptic drugs (AEDs). This paper presents an individual patient-sampling model to assess the cost-effectiveness of using newer AEDs as add-on therapy in line with UK prescribing guidance. METHODS: Identification of the relevant parameters and treatment pathways for the model were achieved by a systematic review of the literature and discussions with clinical experts. Data were obtained from the literature and supplemented with data elicited from paediatric neurologists. The model considered paediatric patients over the period of childhood from the age of diagnosis to 18 years. RESULTS: The results suggest that the older and newer AEDs are similar in terms of drug retention rates and the average time in 'good' treatment outcomes. In terms of cost, the results indicate a consistent increase in cost (compared to older AEDs) when all of the newer AEDs are considered. The decision analysis results indicate that there are no important health benefits from the use of newer AEDs when used as add-on therapy. However, the analysis also reveals that the uncertainties in the model are greater than the differences between the drug strategies. CONCLUSIONS: To develop guidelines on the appropriate use of newer AEDs, better information is required from randomised controlled trials as there is insufficient data available in the public domain to accurately estimate the nature of the trade off between older versus newer AEDs.  相似文献   
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The disparities in health care and health outcomes between the majority population and cultural and racial minorities in the United States are a problem that likely is influenced by the lack of culturally competent care. Emergency medicine and other primary-care specialties remain on the front lines of this struggle because of the nature of their open-door practice. To provide culturally appropriate care, health care providers must recognize the factors impeding cultural awareness, seek to understand the biases and traditions in medical education potentially fueling this phenomenon, and create a health care community that is open to individuals' otherness, thus leading to better communication of ideas and information between patients and their health care providers. This article highlights the rationale for and current problems in teaching cultural competency and examines several different models implemented to teach and promote cultural competency along the continuum of emergency medicine learners. However, the literature addressing the true efficacy of such programs in leading to long-lasting change and improvement in minority patients' clinical outcomes remains insufficient.  相似文献   
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BACKGROUND: Economically disadvantaged African American youth are especially vulnerable to the effects of pediatric asthma and are at increased risk for difficulties in daily functioning. Measures of health-related quality of life (HRQoL) yield important information regarding the impact of pediatric chronic illness on daily functioning. It is essential to develop and validate measures of HRQoL to detect the impact of asthma on this vulnerable population. OBJECTIVE: To examine the psychometric properties of 2 asthma-specific measures of pediatric HRQoL in a sample of economically disadvantaged African American children diagnosed as having asthma. METHODS: One hundred twenty-seven caregivers completed questionnaires regarding their child's HRQoL, asthma symptoms, health care utilization, and school absences and regarding caregiver emotional distress. The severity of the child's asthma was measured via spirometry. RESULTS: The Children's Health Survey for Asthma and the Pediatric Quality of Life Inventory 3.0 Asthma Module demonstrated adequate internal consistency reliability and validity for the present sample. Lower HRQoL was associated with poorer adherence and more health care utilization, asthma symptom days, school absences, and caregiver distress. Only the Children's Health Survey for Asthma was significantly associated with severity, when defined as airway obstruction. CONCLUSIONS: This study supports the psychometric equivalence of 2 condition-specific measures of HRQoL in a population at high risk for asthma and asthma-related problems. The utility of each measure will depend on the needs of the researcher or physician. Both measures can inform the treatment course, help identify and address barriers to treatment adherence, and inform treatment interventions.  相似文献   
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Two previously reported PCR methods were evaluated to determine whether they are as sensitive and specific as conventional culture methods in detecting Salmonella spp. from feces. Bovine and equine feces were enriched overnight in brain heart infusion broth and assayed using PCR methods and primer sets described by other investigators. A total of 774 fecal specimens were tested using a primer set (invE-A primer set) that amplifies a region spanning the invasin E and A genes of Salmonella enterica serovar Typhimurium. A subset of these fecal specimens (306 of the 774 total) were tested using primers (hisJ primer set) that amplify a portion of the histidine transport J gene. The PCR required 24 h to obtain results, whereas it took 5 to 7 days to identify Salmonella spp. by culture. PCR detection of Salmonella spp. using the hisJ primers and the invE-A primers had a sensitivity of 93.3 and 80%, respectively, and a specificity of 85.6 and 98.6%, respectively, compared with bacterial culture. Amplification of 42 culture-negative fecal specimens (of 306 total specimens) generated a DNA fragment that corresponded to the molecular weight of the amplified hisJ gene. The hisJ-generated amplicons from six culture-negative and six culture-positive specimens were sequenced and analyzed using DNA sequence alignment and phylogenetic analysis software. A neighbor-joining dendrogram of the DNA sequences of both sets of hisJ amplicons revealed two distinct groups-one group of amplicons from culture-positive specimens identical to the hisJ gene of S. enterica serovar Typhimurium and a second group of amplicons from culture-negative specimens that were more closely related to hisJ of S. enterica serovar Typhimurium than to other hisJ sequences present in nucleotide databases.  相似文献   
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The current voluntary posthumous organ donation policy fails to provide sufficient organs to meet the demand. In these circumstances xenografts have been regarded as an expedient solution. The public perception seems to be that the only impediments to this technology are technical and biological. There are, however, important ethical issues raised by xenotransplantation that need to be considered as a matter of urgency. When the ethical issues raised by using non-human animals to provide replacement organs for human beings are considered in a wider context and the possible alternatives to xenotransplantation are taken into account, a new dimension is added to the debate. In this broader context it is argued that a less ethically problematic solution is to adopt a presumed consent or opt-out organ procurement policy to regulate posthumous organ harvesting from humans. If there are still too few organs available, then the whole question of transplantation must be reassessed.This revised version was published online in October 2005 with corrections to the Cover Date.  相似文献   
10.
OBJECTIVE: Homozygosity for variants of the methylenetetrahydrofolate reductase (MTHFR) gene is associated with decreased risk for colorectal cancer. We have investigated the relationships between two variants of the MTHFR gene (C677T and A1298C) and blood folate, homocysteine, and genomic stability (strand breakage, misincorporated uracil, and global cytosine methylation in lymphocytes) in a study of 199 subjects. RESULTS: The frequencies of homozygosity for the C677T and A1298C variants of the MTHFR gene were 12.6% and 14.6%, respectively. Plasma homocysteine, folate, vitamin B12, 5-methyltetrahydrofolate, and RBC folate were determined in the C677T genotypes. Plasma folate was significantly lower (P < 0.001) in the homozygous variants (6.7 +/- 0.6 ng/mL) compared with wild-types (8.8 +/- 0.4 ng/mL) and heterozygotes (9.1 +/- 0.5 ng/mL). Homocysteine was significantly higher (P < 0.05) in homozygous variants (13.2 +/- 1.1 micromol/L) compared with homozygous subjects (10.9 +/- 0.4 micromol/L). Homozygous variants had significantly lower (P < 0.05) RBC folate (84.7 +/- 6.3 ng/mL) compared with wild-types (112.2 +/- 5.2 ng/mL) and heterozygous individuals (125.1 +/- 6.6 ng/mL). No significant difference in RBC folate was observed between wild-types and heterozygotes. The A1298C variant did not influence plasma homocysteine, folate, 5-methyltetrahydrofolate, vitamin B12, or RBC folate. Lymphocyte DNA stability biomarkers (strand breaks, misincorporated uracil, and global DNA methylation) were similar for all MTHFR C677T or A1298C variants. CONCLUSION: Data from this study do not support the hypothesis that polymorphisms in the MTHFR gene increase DNA stability by sequestering 5,10-methylenetetrahydrofolate for thymidine synthesis and reducing uracil misincorporation into DNA.  相似文献   
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