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Background contextEvidence-based medicine (EBM) should be the ultimate force driving change in clinical practice. This process generally occurs through a trickle-down phenomenon by which practice recommendations are revised, modified, and/or changed based on the best published data. Recommendations are subsequently incorporated by individual physicians. The fundamental assumption that drives this paradigm is that adopting evidence-based recommendations and/or treatment guidelines will result in improved outcomes. Unfortunately, to date, the paradigm does not have an effective feedback loop that would then evaluate whether the changes did, in fact, improve outcomes.PurposeTo explore the process of clinical audits as a mechanism by which to provide a feedback loop to evaluate the results of spinal surgery on an individual basis and whether those results can be improved.Study designReview article, discussion.MethodsA literature review of the current data regarding clinical audits was performed, and a discussion of how they may apply to spinal surgery is offered.ResultsClinical audits have been used outside the United States, particularly in the United Kingdom, to fulfill this function. A clinical audit would allow a practicing spinal surgeon to examine his or her individual experience and determine if it is achieving the expected outcome based on published results. In the most important feature of a clinical audit, the reaudit, if an individual's results are found to be inconsistent with published results, it presents an opportunity to identify if there are reconcilable differences from which potential improvements can be made. Effectively, this “closes the loop” between EBM and actual clinical practice.ConclusionsDocumenting improved outcomes through the audit process can impact spinal care in several ways. Patients would receive a clear message that their doctors are interested in improving care. Hospitals will use the information to optimize treatment algorithms. Finally, insurers might make the audit process more tenable or attractive by indicating a physician's voluntary participation as a criterion to be a preferred provider.  相似文献   
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PURPOSE

Perceived color of ceramics changes by the spectral power distribution of ambient light. This study aimed to quantify the amount of shifts in color and color coordinates of clinically simulated seven all-ceramics due to the switch of three ambient light sources using a human vision simulating spectroradiometer.

MATERIALS AND METHODS

CIE color coordinates, such as L*, a* and b*,of ceramic specimens were measured under three light sources, which simulate the CIE standard illuminant D65 (daylight), A (incandescent lamp), and F9 (fluorescent lamp). Shifts in color and color coordinate by the switch of lights were determined. Influence of the switched light (D65 to A, or D65 to F9), shade of veneer ceramics (A2 or A3), and brand of ceramics on the shifts was analyzed by a three-way ANOVA.

RESULTS

Shifts in color and color coordinates were influenced by three factors (P<.05). Color shifts by the switch to A were in the range of 5.9 to 7.7 ΔE*abunits, and those by the switch to F9 were 7.7 to 10.2; all of which were unacceptable (ΔE*ab > 5.5). When switched to A, CIE a* increased (Δa*: 5.6 to 7.6), however, CIE b* increased (Δb*: 4.9 to 7.8) when switched to F9.

CONCLUSION

Clinically simulated ceramics demonstrated clinically unacceptable color shifts according to the switches in ambient lights based on spectroradiometric readings. Therefore, shade matching and compatibility evaluation should be performed considering ambient lighting conditions and should be done under most relevant lighting condition.  相似文献   
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PURPOSE: Deterioration of local immunity in the adenoids may make them vulnerable to infection by microorganisms, resulting in otitis media with effusion. To determine the factors associated with this condition, we evaluated adenoid size, mucosal barrier, squamous changes of ciliated epithelium, IgA secretion, and BCL-6 expression in adenoids. MATERIALS AND METHODS: Seventeen children diagnosed with otitis media with effusion (OME group) and 20 children without any history of OME (control group) were enrolled. Their adenoids were sized by lateral view X-ray and stained with hematoxylin and eosin to detect squamous metaplasia. The adenoids were also stained with cytokeratin to evaluate mucosal barriers, and with anti- IgA antibody and anti- BCL-6 antibody to determine expression of IgA and BCL-6. RESULTS: The OME group showed greater incidence of squamous metaplasia, fewer ciliated cells, and lower expression of BCL-6 (p < 0.05 each). Deterioration of the mucosal barrier was detected in the OME group (p > 0.05). IgA secretion and adenoid size were the same for the OME and the control groups. CONCLUSION: These results suggest that increased squamous metaplasia and lower BCL-6 expression in adenoids may be associated with increased susceptibility to OME.  相似文献   
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