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《Radiologia》2014,56(5):451-462
Different types of critically appraised topics (CATs) can be elaborated in diagnostic imaging: comparison of diagnostic tests, evaluation of techniques for early detection (screening), economical analyses, or therapeutic aspects, among others. Their design will vary in function of the question they aim to answer. For example, for treatment evaluation, clinical trials are the best, but if there are secondary studies (systematic reviews or meta-analyses) that synthesize information from several studies, the results will be more important and the scientific conclusions will be more relevant. Regardless of the study design used, the elaboration of a CAT will involve six steps: 1) question; 2) systematic and efficient bibliographic search; 3) levels of evidence (choosing the articles that have the best level); 4) critical reading of the articles chosen; 5) applying conclusions to the context, and 6) recommendations. In this article, we will describe these steps and the nuances for different types of studies in each step.  相似文献   
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《Brain stimulation》2021,14(5):1059-1067
BackgroundThere is still a lack of controlled studies to prove efficacy of thalamic deep brain stimulation for Tourette's Syndrome.ObjectivesIn this controlled trial, we investigated the course of tic severity, comorbidities and quality of life during thalamic stimulation and whether changes in tic severity can be assigned to ongoing compared to sham stimulation.MethodsWe included eight adult patients with medically refractory Tourette's syndrome. Bilateral electrodes were implanted in the centromedian-parafascicular-complex and the nucleus ventro-oralis internus. Tic severity, quality of life and comorbidities were assessed before surgery as well as six and twelve months after. Short randomized, double-blinded sham-controlled crossover sequences with either active or sham stimulation were implemented at both six- and twelve-months’ assessments. The primary outcome measurement was the difference in the Yale Global Tic Severity Scale tic score between active and sham stimulation. Adverse events were systematically surveyed for all patients to evaluate safety.ResultsActive stimulation resulted in significantly higher tic reductions than sham stimulation (F = 79.5; p = 0.001). Overall quality of life and comorbidities improved significantly in the open-label-phase. Over the course of the trial two severe adverse events occurred that were resolved without sequelae.ConclusionOur results provide evidence that thalamic stimulation is effective in improving tic severity and overall quality of life. Crucially, the reduction of tic severity was primarily driven by active stimulation. Further research may focus on improving stimulation protocols and refining patient selection to improve efficacy and safety of deep brain stimulation for Tourette's Syndrome.  相似文献   
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目的:探讨彩色多普勒超声检查在结肠癌诊断中的应用价值。方法回顾性分析该院2012年10月-2013年6月经手术和病理证实的8例结肠癌患者的彩色多普勒超声检查资料。结果术前彩色多普勒超声诊断结肠癌7例,1例误诊为回盲部隆起型高分化腺癌伴大片坏死术前诊断阑尾周围脓肿。结论彩色多普勒超声检查对结肠癌及其并发症的诊断和手术范围的选择提供了可靠的依据。  相似文献   
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《Renal failure》2013,35(5):709-717
Objective.?It has become common practice to use a day-case based approach to identify from the population of hypertensive patients those with an identifiable cause. We aimed to prospectively identify 96 consecutive hypertensive patients undergoing an algorithmic investigation protocol based around two day case hospital attendances. Methods.?The overall diagnostic yield and associated costs were recorded and the patients were observed for a mean of 2.5 years with ambulatory blood pressure (BP) monitoring every three months. Results.?A secondary cause of hypertension was identified in 18.1% of patients, three quarters of whom had renovascular disease. There was a fall in blood pressure with time (157/97 vs. 140/85) but this was associated with an increase in the amount of medication required (mean medication score 5.99 vs. 7.65). Improvement in BP occurred irrespective of whether or not a secondary cause was identified. Only 3.2% of patients were cured of their hypertension as a result of enrollment in the protocol. The cost of identifying each case of secondary hypertension was Euro 10, 196. Conclusions.?A comprehensive protocol aimed at identifying secondary hypertension had a low yield, the majority of whom had renovascular disease. In light of recent data illustrating the lack of improvement in BP following dilatation or bypass of atherosclerotic renovascular disease, it is debatable whether searching for it is justifiable.  相似文献   
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Introduction

Invasive respiratory support is a cornerstone of Critical Care Medicine, however, protocols for withdrawal of mechanical ventilation are still far from perfect. Failure to extubation occurs in up to 20% of patients, despite a successful spontaneous breathing trial (SBT).

Methods

We prospectively included ventilated patients admitted to medical and surgical intensive care unit in a university hospital in northern Mexico. At the end of a successful SBT, we measured diaphragmatic shortening fraction (DSF) by the formula: diaphragmatic thickness at the end of inspiration – diaphragmatic thickness at the end of expiration/diaphragmatic thickness at the end of expiration × 100, and the presence of B-lines in five regions of the right and left lung. The primary objective was to determine whether analysis of DSF combined with pulmonary ultrasound improves prediction of extubation failure.

Results

Eighty-two patients were included, 24 (29.2%) failed to extubation. At univariate analysis, DSF (Youden's J: >30% [sensibility and specificity 62 and 50%, respectively]) and number of B-lines regions (Youden's J: >1 zone [sensibility and specificity 66 and 92%, respectively]) were significant related to extubation failure (area under the curve 0.66 [0.52–0.80] and 0.81 [0.70–0.93], respectively). At the binomial logistic regression, only the number of B-lines regions remains significantly related to extubation failure (OR 5.91 [2.33–14.98], P < .001).

Conclusion

In patients with a successfully SBT, the absence of B-lines significantly decreases the probability of extubation failure. Diaphragmatic shortening fraction analysis does not add predictive power over the use of pulmonary ultrasound.  相似文献   
108.
ObjectiveTo explore attitudes and practices of physicians relating to accessible medical diagnostic equipment in serving patients with mobility disability.DesignOpen-ended individual telephone interviews, which reached data saturation. Interview recordings were transcribed verbatim for qualitative conventional content analysis.SettingMassachusetts, the United States, October 2017-January 2018.ParticipantsPracticing physicians from 5 clinical specialties (N=20).InterventionsNot applicable.Main Outcome MeasuresCommon themes concerning physical accessibility.ResultsMean ± SD time in practice was 27.5±12.5 years; 14 practices had height-adjustable examination tables; and 7 had wheelchair-accessible weight scales. The analysis identified 6 broad themes: height-adjustable examination tables have advantages; height-adjustable examination tables have drawbacks; transferring patients onto examination tables is challenging; rationale for examining patients in their wheelchairs; perceptions of wheelchair-accessible weight scales; and barriers and facilitators to improving physical accessibility. Major barriers identified by participants included costs of equipment, limited space, and inadequate payment for extra time required to care for persons with disability. Even physicians with accessible examination tables sometimes examined patients seated in their wheelchairs.ConclusionsEven if physicians have accessible equipment, they do not always use it in examining patients with disability. Future efforts will need to consider ways to eliminate these access barriers in clinical practice. Given small sample size, results are not generalizable to physicians nationwide and globally.  相似文献   
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