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51.
Impact of clinical history on fracture detection with radiography   总被引:3,自引:0,他引:3  
The effect of knowledge of localizing symptoms and signs in the detection of fractures was studied. Forty radiographs of the extremities were examined twice by seven radiologists; the sessions were separated by 4 months. In 26 cases, a subtle fracture was present; 14 cases were normal. In half of the cases at each session, the precise location of pain, tenderness, or swelling was provided. The observer was asked to determine if the case was normal or abnormal (provide the exact location of the fracture) and to indicate the degree of confidence in the diagnosis. Responses were converted to a numeric scale for analysis. Analysis of receiver operator characteristic parameters indicates that clues regarding location of trauma facilitate detection of fractures. The improvement is based largely on an increased true-positive rate without an increased false-positive rate, regardless of the decision criteria of the radiologist (overall willingness to "overread" or "underread"). This has direct clinical applicability and reinforces the plea of radiologists for precise clinical information.  相似文献   
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Introduction

New digital thoracic drainage systems allow an objective measurement of air leakage. They have proven their usefulness in the postoperative thoracic surgery in adults, but there is little experience with its use in the pediatric population. The objective of our study is to analyze their safety and effectiveness in the postoperative period of the pediatric patients.

Method

A prospective consecutive observational study was done. All patients submitted to pulmonary resection between 2011 and 2017 and in whom digital thoracic drainage system was used (Thopaz Chest Drain System, Medela, Switzerland) were prospectively enrolled in this study. We analyzed variables: duration of chest tube (CT), days of hospitalization and radiographs in the immediate postoperative period related to the presence of CT. This group was compared with a historical cohort of patients (from 2011 to 2015) with a pulmonary resection in whom the traditional thoracic drainage was used. For the statistical analysis, the Mann–Whitney U-Test was used for independent samples.

Result

Twenty-six patients were included, Digital drainage system was used in13 patients and traditional drainage was used in 13 patients. The median age was 18?months (12?days-14?years). The mean number of days with the chest tube was 1.69?±?0.6 in digital drainage group versus 5.38?±?4?days in traditional drainage group (p?<?0.05) The mean number of postoperative radiographs was 2.8?±?1.1 in digital drainage group versus 6.23?±?5.2 radiographs in traditional drainage group (p?<?0.05). The average hospital stay in digital drainage group was 5.69?±?2.7?days versus 7?±?4.7?days in the traditional drainage group (p?>?0.05). No complications related to the use of digital drainage group were registered.

Conclusion

The digital thoracic drainage systems provide an objective measurement of air leakage, allowing early chest tube removal and decreasing the number of radiographs performed postoperatively. Its use in the pediatric population appears to be safe and potentially beneficial.

Level of evidence

II.  相似文献   
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Evans  EA; Mohandas  N 《Blood》1987,70(5):1443-1449
Micropipette aspiration tests on single erythrocytes have previously shown that the static rigidity (membrane shear modulus) of oxygenated sickle cells increased with increasing hemoglobin concentration, whereas the rigidity of normal cells was independent of hemoglobin concentration. Moreover, it was observed that after mechanical extension, sickle cells exhibited persistent deformation more frequently and to a greater extent than normal cells. To ascertain if differences in association of normal and sickle hemoglobin with the membrane could account for these observations, we measured rheologic properties of normal membranes reconstituted with sickle hemoglobin and sickle membranes reconstituted with normal hemoglobin. The static rigidity of normal ghosts reloaded with sickle hemoglobin was higher than those of either normal ghosts reloaded with normal hemoglobin or native normal cells. On the other hand, the increased rigidity of native sickle cells decreased to near-normal values following reconstitution with normal hemoglobin. Furthermore, we observed that normal ghosts reconstituted with sickle hemoglobin exhibited persistent bumps after mechanical extension, but no bumps formed on normal ghosts reconstituted with normal hemoglobin. Moreover residual bumps were not produced on sickle cells reloaded with normal hemoglobin. Since mechanical characteristics peculiar to sickle cells could be induced in normal cells by incorporation of sickle hemoglobin, and since normal characteristics could be restored to sickle cells by incorporation of normal hemoglobin, we suggest that the interaction of sickle hemoglobin with the cell membrane is responsible for augmented static rigidity of oxygenated sickle erythrocytes.  相似文献   
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Interleukin (IL)-20 belongs to the IL-10 family and is a potent immunomodulatory cytokine with implications for pathogenesis in the inflammatory bowel disease (IBD). The interleukin 20 gene is located within a 200 kb region of q31-32 locus of chromosome 1. No previous studies have reported this novel association between ulcerative colitis (UC) and IL-20 polymorphisms. In the present work, we evaluated the role of IL-20 gene polymorphisms as susceptibility markers for UC. Three polymorphisms of IL-20 gene (rs2981573, rs2232360, rs1518108) were genotyped by 5′ exonuclease TaqMan genotyping assays on an ABI Prism 7900 HT Fast Real-Time PCR system in a group of 198 Mexican Mestizo patients with UC and 698 ethnically matched healthy unrelated individuals with no family history of UC. We found significant decreased frequencies of two IL-20 genotypes: GG (rs2981573) [10.6% vs. 17.6%, p = 0.017, OR = 0.55, 95% CI: 0.33–0.93] and GG (rs2232360) [10.6% vs. 17.6%, p = 0.017, OR = 0.55, 95% CI: 0.33–0.93] in UC patients as compared to healthy controls. No significant differences of gene frequencies were found between UC patients and healthy controls in the rs1518108 polymorphism. In the subgroup analysis, no differences were found between the IL-20 genotypes and the clinical characteristics of UC. The results suggest that the GG genotypes of the IL-20 polymorphisms (rs2981573 and rs2232360) might have an important role in the development of UC in the Mexican population.  相似文献   
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