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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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Mucosa isolated from the proximal third of the small intestine of infant rats had much lower cyclic nucleotide concentrations (expressed both per unit wet weight and per unit DNA content) than those determined in the intestinal wall. The steady-state concentrations of both cyclic AMP and cyclic GMP in jejunum showed dramatic increases during the first 5 d post partum. Another increase in cyclic nucleotide concentrations was observed in the isolated mucosa between d 15 and 21. Starvation for 24 h always resulted in lower intestinal cyclic nucleotide concentrations than those of the fed littermates. This effect was more pronounced in younger animals and more evident for cyclic AMP values. Three-week-old rats fed a high carbohydrate diet for 24-48 h exhibited more pronounced elevations in the concentrations of cyclic nucleotides from the jejunal mucosa than did rats fed a high fat diet.  相似文献   
4.
The transurethral resection syndrome has not previously been described after bladder surgery. This article reports four patients who developed signs of this syndrome after transurethral resection of bladder tumours (TURB). Symptoms included abdominal pain, arterial hypotension, nausea and vomiting. There was evidence in all cases that the cause was absorption of irrigating fluid by the extravascular route. Fluid absorption was detected by ethanol in two patients and the urologist noted a perforation during the third operation. The most complicated clinical course occurred in the case where there was a delay of three hours before the diagnosis was made. Medical treatment consisted of antiemetics and volume expansion of the extracellular fluid compartment as extravasation is associated with hypovolaemia. Diuretics were not given until the circulation had been restored.  相似文献   
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Conventional radiographs do not always make it possible to confirm a diagnosis of ischemic necrosis of the lunate in the early stages of disease. For these doubtful cases MRI is justifiable in addition, to diagnose or to rule out ischemic necrosis of the lunate.  相似文献   
6.
Kniearthrodesen     
When arthrodesis of the knee is indicated, the operative procedure selected for fixation depends on the condition of the soft tissues, the bone stock, whether infection is present, and the age of the patient and his or her capacity for partial weight-bearing. In young patients with no infection or soft tissue problems, when adequate bone stock is present compression plating or the use of an intramedullary nail is possible and allows stable fixation. Soft tissue problems with defect(s) or infection are a good indication for the use of an external fixator. The most common indication for knee arthrodesis is a failed total knee prosthesis that has become infected. Deficient bone stock with osteopenic bone or a defect after failed total knee arthroplasty are problems that can be solved by the use of modular fusion nail systems, especially in older patients. These systems are more comfortable for the patient than external fixation devices and allow early full weight-bearing.  相似文献   
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Antibody-dependent cellular cytotoxicity (ADCC) activity against pseudorabies virus-infected target cells has been found to be lower in young pig peripheral blood leukocytes (PBLs) than in adults. Experiments were designed to investigate the reason(s) for low activity in the young, which are more at risk of fatal infection than adults. The percentage of polymorphonuclear leukocytes (PMNs), the major ADCC effector cell, in the whole leukocyte population did not have a bearing on the deficiency. Enrichment for PMNs did not alleviate differences in activity between young and adult pigs. Additionally, no suppressor cell(s) or factor(s) could be demonstrated to account for the ADCC deficiency. The source of the ADCC deficiency in the young was found to be related to the decreased ability of young pig effector cells to bind antibody-sensitized targets. This deficiency relative to adults was associated with decreased antibody binding to high affinity Fc receptors on young pig neutrophils.  相似文献   
10.
An important aim of proctocolectomy with ileal pouch-anal anastomosis (IPAA) is to maintain anal continence. Anal sphincter disruption during IPAA is felt to play an important role in loss of continence, which is described in up to 30% of the treated patients in the early postoperative period. Although sphincter function recovers gradually after surgery, some patients stay incontinent. In our investigation of possible parameters involved in preservation of continence after this operative procedure, we focused on changes in anal manometry. We compared these findings with the functional results obtained by questioning the patients and physical examination. Anal manometry was performed with a low-compliance hydraulic perfusion system. All patients underwent a J-pouch procedure with a short rectal cuff for ileoanal reconstruction. We examined 25 patients, 13 underwent operation for the treatment of ulcerative colitis, 12 because of adenomatous polyposis. In the colitis and polyposis group, 28% of the patients reported events of soiling. Three patients (12%) were incontinent. The remaining 15 patients were completely continent. The median time after operation was 58 months, ranging from 12 to 96 months. Comparing the results of anal manometry with standard values of ten age- and gender-matched healthy volunteers, it was found that there was a significant increase in the threshold of balloon awareness and urge to defecate. These sensations were sometimes elicited by pouch contractions. Median pouch- compliance was also clearly elevated in comparison to rectal compliance (P<0.005). Inhibitory reflexes during balloon inflation could not be evoked in any of the patients. Comparing continent with incontinent patients there were significant differences in balloon awareness, urge to defecate, and stool frequency (P<0.01,P<0.01 andP<0.001, respectively). But in contrast to other publications, we could not find significant differences in anal sphincter length, resting and squeezing, anal canal pressure. Pouch compliance was lowered in incontinent patients and negatively correlated with stool frequency (P<0.001,r=?0.82). In conclusion, our study indicates that anal sphincter resting pressure alone is not a crucial factor in continence preservation in the long-term after total proctocolectomy and IPAA. Poor pouch- compliance and concomitant higher stool frequencies seem to be related to incontinence in this patient group.  相似文献   
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