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1.
Image fusion is a process of combining information from multiple sensors. It is a useful tool implemented in the treatment planning programme of Gamma Knife Radiosurgery. In this paper we evaluate advanced image fusion algorithms for Matlab platform and head images. We develop nine level grayscale image fusion methods: average, principal component analysis (PCA), discrete wavelet transform (DWT) and Laplacian, filter - subtract - decimate (FSD), contrast, gradient, morphological pyramid and a shift invariant discrete wavelet transform (SIDWT) method in Matlab platform. We test these methods qualitatively and quantitatively. The quantitative criteria we use are the Root Mean Square Error (RMSE), the Mutual Information (MI), the Standard Deviation (STD), the Entropy (H), the Difference Entropy (DH) and the Cross Entropy (CEN). The qualitative are: natural appearance, brilliance contrast, presence of complementary features and enhancement of common features. Finally we make clinically useful suggestions.  相似文献   
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OBJECTIVES: To illustrate the types of injuries seen by the accident and emergency department as a result of the use of non-motorized 'microscooters' in children, and to increase awareness of scooter-related triplane fractures of the ankle. STUDY DESIGN: A retrospective study conducted in an accident and emergency department of a district general hospital on all children who had a scooter-related limb injury over a 6-month period and were referred for orthopaedic review. METHODS: The analysis involved a case note review. Information recorded included the injury sustained, protective equipment worn at the time of the accident and management by the orthopaedic team. RESULTS: Scooter injuries accounted for 10 fractures in this period. There were three 'triplanar' injuries, which required operative fixation, and three injuries requiring manipulation under anaesthesia. No protective gear was worn by any of the patients. CONCLUSION: The popularity of microscooters seems to represent a significant risk of bony injury in the paediatric population. Medical personnel who manage acute paediatric trauma should be aware of scooter-related triplanar ankle injuries.  相似文献   
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This study was sought to evaluate the relationship between Her-2 protein expression, cellular localization, gene amplification, and other clinicopathologic parameters in colorectal carcinomas. Her-2 protein expression and gene amplification were assessed in paraffin sections from 106 primary colorectal adenocarcinoma cases using immunohistochemistry and fluorescence in situ hybridization. Both membranous and cytoplasmic immunostaining was evaluated. The results were correlated with each other and with tumor grade, stage, and overall survival. Membranous and cytoplasmic protein expression was identified in 6 (5.6%) and 13 (12.26%) cases, respectively. Gene amplification was detected in 4 (3.7%) cases. There was a high concordance between membranous protein expression and gene amplification (kappa=0.791). No apparent association with any of the clinicopathologic parameters was identified. Membranous Her-2 protein expression and gene amplification are encountered in a small subset of colorectal carcinomas and are highly concordant events. Cytoplasmic protein expression might be either artifactual or it might represent a cross-reacting protein or a precursor form of the mature protein.  相似文献   
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Hepatitis E is considered an emerging disease that may be a threat in both developing and industrialized countries all over the world. The risk of chronic hepatitis E virus infection is higher among immunocompromised patients. This study aimed to assess the status of hepatitis E infection in patients with transfusion‐dependent thalassaemia from a single centre, in Greece. Our results suggest that the prevalence of hepatitis E infection in this group of patients is low.  相似文献   
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In 2008, the New Jersey Department of Health (NJDOH) identified a 21.1% increase in reported invasive pneumococcal disease (IPD). In 2009, NJDOH piloted nucleic acid-based serotyping to characterize serotypes causing IPD. From April through September, NJDOH received specimens from 149 of 302 (49%) case patients meeting our case definition. An uncommon serotype, 10A, accounted for 25.2% of IPD overall and was identified in 12 counties, but it was associated with one county (rate ratio = 5.4, 95% confidence interval [CI] 2.1, 11.8). NJDOH subsequently conducted a case-control study to assess the presentation of and clinical risk factors for 10A IPD. Case patients with 10A IPD were more likely to have had immunosuppression, asthma, and multiple chronic medical conditions than control subjects had (odds ratio [OR] = 2.6, 95% CI 1.1, 6.3; OR=4.7, 95% CI 1.7, 13.2; and OR=2.3, 95% CI 1.0, 5.2, respectively). State-based pneumococcal serotype testing identified an uncommon serotype in New Jersey. Continued pneumococcal serotype surveillance might help the NJDOH identify and respond to future serotype-specific increases.Streptococcus pneumoniae (S. pneumoniae) is a leading cause of bacterial pneumonia, bacteremia, and meningitis. In 2008, the New Jersey Department of Health (NJDOH) observed a 21.1% increase in reported invasive pneumococcal disease (IPD) compared with IPD cases reported in 2007 (95% confidence interval [CI] 8.6, 35.2, 8.33 cases/100,000 population in 2008 vs. 6.88 cases/100,000 population in 2007), including increases in four counties. In response, in 2009, NJDOH began a pilot project to characterize the serotypes causing IPD and to determine if serotypes not included in current vaccines contributed to these increases. When our investigation identified an unusual serotype, 10A, NJDOH conducted a case-control study to assess the presentation of and clinical risk factors for 10A IPD.  相似文献   
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Background: The study aimed to test the hypothesis that computer‐based calculation of malnutrition risk may enhance the ability to identify pediatric patients at malnutrition‐related risk for an unfavorable outcome. The Pediatric Digital Scaled MAlnutrition Risk screening Tool (PeDiSMART), incorporating the World Health Organization (WHO) growth reference data and malnutrition‐related parameters, was used. Materials and Methods: This was a prospective cohort study of 500 pediatric patients aged 1 month to 17 years. Upon admission, the PeDiSMART score was calculated and anthropometry was performed. Pediatric Yorkhill Malnutrition Score (PYMS), Screening Tool Risk on Nutritional Status and Growth (STRONGkids), and Screening Tool for the Assessment of Malnutrition in Pediatrics (STAMP) malnutrition screening tools were also applied. PeDiSMART's association with the clinical outcome measures (weight loss/nutrition support and hospitalization duration) was assessed and compared with the other screening tools. Results: The PeDiSMART score was inversely correlated with anthropometry and bioelectrical impedance phase angle (BIA PhA). The score's grading scale was based on BIA Pha quartiles. Weight loss/nutrition support during hospitalization was significantly independently associated with the malnutrition risk group allocation on admission, after controlling for anthropometric parameters and age. Receiver operating characteristic curve analysis showed a sensitivity of 87% and a specificity of 75% and a significant area under the curve, which differed significantly from that of STRONGkids and STAMP. In the subgroups of patients with PeDiSMART‐based risk allocation different from that based on the other tools, PeDiSMART allocation was more closely related to outcome measures. Conclusion: PeDiSMART, applicable to the full age range of patients hospitalized in pediatric departments, graded according to BIA PhA, and embeddable in medical electronic records, enhances efficacy and reproducibility in identifying pediatric patients at malnutrition‐related risk for an unfavorable outcome. Patient allocation according to the PeDiSMART score on admission is associated with clinical outcome measures.  相似文献   
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In this pictorial essay, we review and discuss the varying morphologic characteristics of scrotal appendages and calculi. Characteristic sonograms obtained from patients with coexisting hydrocele are presented, and recent literature is included. Hydrocele greatly facilitates the imaging of these intrascrotal structures, as it acts as a “water path”. On the one hand, torsion of a scrotal appendage should always be included in the differential diagnosis of acute scrotum, especially in children. On the other hand, scrotolithiasis may occasionally cause mild discomfort. As a consequence, and given the widespread use of sonography for the evaluation of both acute and chronic conditions of the scrotum, radiologists should be familiar with these entities.  相似文献   
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