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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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1. The frequent occurrence of hypothalamo-pituitary dysfunction in patients with eating disorders as well as prior reports that nutritional and endocrine status influence pituitary morphology, led us to hypothesize that pituitary size and shape may be altered in patients with eating disorders. 2. Magnetic resonance imaging (MRI) does not use ionizing radiation and is currently one of the most feasible modalities available to study the pituitary gland in vivo. Using MRI, we have previously reported in a preliminary study that female patients with eating disorders had significantly smaller pituitary glands than controls. In addition MRI excluded any pituitary mass lesions. 3. In this report, we confirm our previous MRI findings and provide further evidence of pituitary abnormalities in an expanded sample of eating disorder patients. Preliminary data on pituitary volume estimates from MRI scans are provided for a subset of patients and controls.  相似文献   
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Periodic, lateralized, epileptiform discharges (PLEDs) in the electroencephalogram have been reported in association with a variety of structural lesions of the brain. Although a great deal of attention has been directed to the neuropathological basis of PLEDs, little emphasis has been placed on the functional basis of this EEG syndrome. In this paper, we reported a patient with multiple systemic problems whose EEG showed PLEDs. However, radiological and pathological studies revealed no neuropathological basis for the occurrence of this EEG syndrome. Thus, we presented evidence that metabolic factors may play a part in the pathogenesis of PLEDs.  相似文献   
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Dental treatment is a dyadic encounter. Yet research on the dentist-patient dyad has tended to focus on patient perceptions of dentist, to the neglect of dentist perceptions of patient. Previous theoretic and qualitative work on caregiver perceptions of patients suggested three dimensions of evaluation. Dentists (N=618) rated their patients on items taken from two prior studies. Dentists' responses were subjected to confirmatory factor analysis. The analysis substantiated the existence of three evaluative dimensions: compliance, tractability, and likability. Further analysis showed that the three dimensions formed a Guttman simplex, revealing a second-order factor of selectivity and allowing a classification of dentists on the basis of patient selectivity.This study was funded by a grant from the University of Connecticut Research Foundation.  相似文献   
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A magnetic resonance imaging study of putamen nuclei in major depression.   总被引:7,自引:0,他引:7  
The basal ganglia are recognized as putative mediators of certain cognitive and behavioral symptoms of major depression. Moreover, patients with basal ganglia lesions have repeatedly exhibited significant affective symptomatology, including apathy, depressive mood, and psychosis. Using high resolution, axial T2 intermediate magnetic resonance images, and a systematic sampling stereologic method, we assessed putamen nuclei volumes in 41 patients with major depression (DSM-III) and 44 healthy volunteer controls of similar age. Depressed patients had significantly smaller putamen nuclei compared with controls. Age was negatively correlated with putamen size in both groups. These results are the first demonstration of diminished putamen volumes in depression and further support a role for basal ganglia structures in the etiopathogenesis of depression.  相似文献   
9.
Current perspectives on childhood depression: an overview   总被引:2,自引:0,他引:2  
The rapidly increasing research interest in childhood depression indicates that it has become a recognized disorder. The authors review the literature on depression in children, focusing on epidemiology, various diagnostic criteria, classification schemes, assessment instruments, and intervention studies that have been applied to childhood depression. Given that there are many etiological factors, it will be important to study the disorder from various conceptual frameworks, including biochemical, genetic learned helplessness, life stresses, cognitive distortion, behavioral reinforcement, and sociological models.  相似文献   
10.
The objective of this study was to determine the effectiveness of two autotitrating continuous positive airway pressure (auto-CPAP), the Tranquility (Respironics, Inc., Murrysville, PA, U.S.A.) and the AutoSet T (ResMed Corp., Poway, CA, U.S.A). Patients with obstructive sleep apnea syndrome (OSAS) underwent attended auto-CPAP titration with either the Tranquility or AutoSet T machine. The auto-CPAP machine was given a performance score between 0 and 9. A score of 3 or lower indicated that autotitration had to be discontinued. Sixty patients were studied, 35 patients with the Tranquility machine and 25 patients with the AutoSet T machine. The mean age was 55.4 years, whereas the mean body mass index (BMI) was 32.7. The mean respiratory disturbance index (RDI) was 37.5, and the mean arousal index before use of auto-CPAP was 41.4. The two treatment groups were comparable in age, BMI, RDI, and arousal index. The mean performance scores for the Tranquility and AutoSet T machines were not statistically different. Autotitration with the Tranquility machine had to be discontinued in 10 of the 35 patients (29%), whereas with the AutoSet T machine, autotitration was discontinued in 11 of the 25 patients (44%). Despite advances in auto-CPAP machines, there remains a large minority of patients with OSAS in whom these machines do not accomplish treatment goals. At this time, these machines are not a substitute for in-laboratory CPAP titration polysomnograms.  相似文献   
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