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21.
Accurate diagnosis of acute appendicitis: a retrospective and prospective analysis of 686 patients. 总被引:1,自引:0,他引:1
J R Izbicki W T Knoefel D K Wilker H K Mandelkow K Müller M Siebeck L Schweiberer 《Acta chirurgica》1992,158(4):227-231
OBJECTIVE--To formulate a score system that would make the preoperative diagnosis of acute appendicitis more accurate. DESIGN--Retrospective then prospective study. SETTING--City University Hospital. SUBJECTS--536 patients who had their appendixes removed between 1981 and 1986 (retrospective study), and 150 consecutive patients admitted with a presumptive diagnosis of appendicitis between 1987 and 1988 (prospective study). MAIN OUTCOME MEASURES--Correlation between the histological diagnosis of appendicitis and variables representing history, clinical examination, and laboratory investigations. RESULTS--The rate of histologically proven negative appendicectomies in the retrospective series was 40% and in the prospective series 33%. The variables that were thought to be predictive were: male sex, white cell count of greater than 11 x 10(9)/l, history of less than 24 hours with no previous complaints, rebound tenderness, shift of pain from the epigastrium, and localised guarding, but all criteria had low specificities and sensitivities when applied prospectively, and combining the scores did not improve them. CONCLUSION--The accurate diagnosis of appendicitis depends largely on the experience of the surgeon and is not improved by the application of a score system that includes the above variables. 相似文献
22.
Reliability of radiographic measurement of fracture angulation in children with femoral shaft fractures 下载免费PDF全文
INTRODUCTION: Clinical decisions are based on x-ray measures of radiographs. However, the reliability of assessing the angular measurement of fractured femurs in children is unknown. The purpose of this study was to determine the intra- and interrater reliability of an x-ray assessment of femoral shaft fracture angulation in children. METHODS: On 2 occasions, 3 raters evaluated 30 radiographs of children aged 4 to 10 years, 3 to 24 months after a femoral fracture. The radiographs were evaluated by an orthopedic surgeon, an orthopedic fellow and a research assistant, using a standardized methodology. Reliability was assessed with the intraclass correlation coefficient (ICC), an index of concordance that ranges from 01, where > 0.75 indicates excellent concordance. RESULTS: The ICC for the intrarater ranged from 0.75 to 0.97. The interrater reliability ICC for anterior or posterior angulation was 0.91 (95% confidence interval [CI] 0.840.95) and for varus or valgus angulation was 0.90 (95% CI 0.790.95). A change in measurement of more than 5 degrees exceeds the variation in measurement and, therefore, can be attributed to a true shift in fracture position. CONCLUSIONS: With specific standardized protocols, radiographic assessment of femoral fractures is reliable, irrespective of the examiner's level of experience. 相似文献
23.
Yang-Sheng Tzeng Eric Hoffman Janice Cook-Granroth Rie Maurer Niral Shah Joey Mansour Juerg Tschirren Mitchell Albert 《Magnetic resonance in medicine》2007,58(3):636-642
An anthropomorphic airway tree phantom was imaged with both hyperpolarized (HP) 3He MRI using a dynamic projection scan and computed tomography (CT). Airway diameter measurements from the HP 3He MR images obtained using a newly developed model-based algorithm were compared against their corresponding CT values quantified with a well-established method. Of the 45 airway segments that could be evaluated with CT, only 14 airway segments (31%) could be evaluated using HP 3He MRI. No airway segments smaller than approximately 4 mm in diameter and distal to the fourth generation were adequate for analysis in MRI. For the 14 airway segments measured, only two airway segments yielded a non-equivalent comparison between the two imaging modalities, while eight more had inconclusive comparison results, leaving only four airway segments (29%) that satisfied the designed equivalence criteria. Some of the potential problems in airway diameter quantification described in the formulation of the model-based algorithm were observed in this study. These results suggest that dynamic projection HP 3He MRI may have limited utility for measuring airway segment diameters, particularly those of the central airways. 相似文献
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Schools of public health have been cautioned about producing graduates and research that were disconnected from public interest. Although institutions may implement a variety of strategies to rectify the situation, institutional structural and cultural barriers impede progress. Public health practice coordinators in accredited schools of public health were surveyed to describe the presence of structural and cultural barriers to academic public health practice using the Stevens model. Administrative leadership and faculty reward systems are described as critical to advance academic public health practice. 相似文献
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Janice Matthews-Greer Dorothy Rivette Rosalina Reyes Catherine F Vanderloos Elba A Turbat-Herrera 《Clinical laboratory science》2004,17(1):8-11
OBJECTIVE: Thirteen specific types of human papillomavirus (HPV), classified as high-risk for the development of cervical cancer, have been reported in 99.7% of all cervical cancers. For this reason, and because of the reported lack of sensitivity of the Papanicolaou (Pap) smear for detecting HPV, some experts believe that the use of papillomavirus DNA testing may replace cytology for routine gynecological screening. Our goal was to validate a commercial assay, the Digene Hybrid Capture-2 for the detection of human papillomavirus by comparing the results to cytological detection of cervical abnormalities. DESIGN: Cytology results of concurrent liquid-based Papanicolaou smears were compared to the Hybrid Capture-2 results. Correlation was assessed and discordant cytology results were reviewed. SETTING: Louisiana State University Health Sciences Center at Shreveport, Department of Pathology, HPV Diagnostic Laboratory. PATIENTS: All liquid cytology specimens submitted for HPV testing between November 1, 2000 and April 1, 2001. RESULTS: Of the 291 cases tested by Hybrid Capture-2, 12% and 28% were positive with the low-risk and high-risk probes, respectively, and 265 had concurrent cytology results. Fourteen specimens testing positive only with the low-risk probe were not included in this comparison. Thus, the results for 251 of the 291 (86%) specimens tested for human papillomavirus DNA were compared to the original cytology report. Overall concordance between Hybrid Capture-2 and the original smear cytology result was 78%. Slide review reduced the number of discordant specimens from 22% to 12%. CONCLUSION: Based upon these data, we find the HPV assay to be useful as a routine screen for Human papillomavirus. 相似文献