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81.
Osteocartilaginous differentiation in malignant melanoma is rare and can pose a diagnostic challenge. In previously reported cases, melanomas were predominantly located on acral and mucosal sites, with osteocartilaginous differentiation present in either primary or recurrent lesions. We report a case of a 52‐year‐old female with malignant melanoma located on the right upper back exhibiting osteosarcomatous differentiation only in the axillary lymph node metastasis. This case serves to highlight that the divergent differentiation can occur in lymph node metastases while being absent in the primary lesion. The patient's medical history, careful histological examination, and immunohistochemistry may be necessary for establishing the correct diagnosis.  相似文献   
82.
Underage drinking is a serious public health problem in the United States, and youth exposure to alcohol advertising has been indicated as a possible contributing factor. Although a number of studies have identified advertising content features that youth find appealing, a key limitation of this research is the absence of a broader tool to examine those features, especially those used by alcohol brands that are popular with underage drinkers. We created an index of content elements found in the research literature to be appealing to youth, and then used this index in a content analysis to identify the degree to which youth-appealing content appeared in a sample of alcohol ads that aired on television shows popular among youth. Finally, using bivariate analysis, we tested the relationship between alcohol brands’ use of this content and the popularity of those brands among youth. We found that many of the ads featured youth-appealing content, and that the ads for the alcohol brands most popular among youth had more youth-appealing content than the less popular brands.  相似文献   
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84.
Segmentation of lung parenchyma from the chest computed tomography is an important task in analysis of chest computed tomography for diagnosis of lung disorders. It is a challenging task especially in the presence of peripherally placed pathology bearing regions. In this work, we propose a segmentation approach to segment lung parenchyma from chest. The first step is to segment the lungs using iterative thresholding followed by morphological operations. If the two lungs are not separated, the lung junction and its neighborhood are identified and local thresholding is applied. The second step is to extract shape features of the two lungs. The third step is to use a multilayer feed forward neural network to determine if the segmented lung parenchyma is complete, based on the extracted features. The final step is to reconstruct the two lungs in case of incomplete segmentation, by exploiting the fact that in majority of the cases, at least one of the two lungs would have been segmented correctly by the first step. Hence, the complete lung is determined based on the shape and region properties and the incomplete lung is reconstructed by applying graphical methods, namely, reflection and translation. The proposed approach has been tested in a computer-aided diagnosis system for diagnosis of lung disorders, namely, bronchiectasis, tuberculosis, and pneumonia. An accuracy of 97.37 % has been achieved by the proposed approach whereas the conventional thresholding approach was unable to detect peripheral pathology-bearing regions. The results obtained prove to be better than that achieved using conventional thresholding and morphological operations.  相似文献   
85.
86.
Epithelioid glioblastoma (e-gbm) is a recently described variant of glioblastoma (GBM) which is associated with short survival and now added as a provisional entity to WHO 2016 classification of CNStumors. About half of these tumors show characteristic BRAF-V600E mutation. However, unlike conventional GBMs, e-gbm lack specific diagnostic and prognostic markers. Hence, we aimed to molecularly characterize these tumors. An extensive review of literature was performed.In a multi-institutional effort, all the cases of glioblastoma of year 2017 were reviewed. Cases with predominant epithelioid morphology were analysed. Seven cases of e-gbm (adults:4 and pediatric: 3) were identified. Duration of symptoms varied from 2 weeks to one month. Radiologically, all cases were supratentorial, contrast enhancing with solid and cystic appearance. Majority of the cases were immunopositive for GFAP (71%), EMA (71%), S100 (71%) and vimentin (85%). All the cases showed ATRX, INI-1 and H3K27me3 expression. BRAFV600Emutation was seen in 28% of cases. TERT mutation was seen in 40% cases, while one case showed EGFR amplification. H3F3A mutations and PTEN deletions were seen in none. Although e-gbms are rare, epithelioid morphology of a CNS tumor in a young adult or children with areas of necrosis needs thorough histomorphological and genetic workup.  相似文献   
87.
Background Candida auris is an emerging multidrug-resistant fungal pathogen associated with bloodstream, wound and other infections, especially in critically ill patients. C. auris carriage is persistent and is difficult to eradicate from the hospital environment.AimWe aimed to pilot admission screening for C. auris in intensive care units (ICUs) in England to estimate prevalence in the ICU population and to inform public health guidance.MethodsBetween May 2017 and April 2018, we screened admissions to eight adult ICUs in hospitals with no previous cases of C. auris, in three major cities. Swabs were taken from the nose, throat, axilla, groin, perineum, rectum and catheter urine, then cultured and identified using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS). Patient records were linked to routine ICU data to describe and compare the demographic and health indicators of the screened cohort with a national cohort of ICU patients admitted between 2016 and 2017.ResultsAll C. auris screens for 921 adults from 998 admissions were negative. The upper confidence limit of the pooled prevalence across all sites was 0.4%. Comparison of the screened cohort with the national cohort showed it was broadly similar to the national cohort with respect to demographics and co-morbidities.ConclusionThese findings imply that C. auris colonisation among patients admitted to ICUs in England is currently rare. We would not currently recommend widespread screening for C. auris in ICUs in England. Hospitals should continue to screen high-risk individuals based on local risk assessment.  相似文献   
88.
A community-based nationwide survey for hearing loss was conducted in Oman in 1996–97. Audiometric tests and ear examinations were conducted for 12 400 persons in phase I. For children aged less than 4 years, subjective screening tests were used. In phase II, otologists examined the hearing-impaired subjects to determine the cause. The prevalence of bilateral hearing impairment was 55/1000 (95% CI 51.08–59.47). Gender difference was not significant. The rates were 325/1000 and 17/1000, respectively, in the _60-year and _10-year age groups. Presbyacusis and middle ear diseases, respectively, were the causes of 33% and 20% of bilateral hearing impairment. In 30% of the bilateral hearing-impaired subjects, the cause could not be determined. The prevalence of bilateral disabling hearing loss was 21/1000 (95% CI 18.07–23.29). Noise-induced trauma was responsible for only 1.4% of cases of disabling hearing loss. Establishing primary ear care, introducing hearing screening for neonates and schoolchildren, promoting safe preventive practices for ear care, strengthening secondary-level ear care services and introducing comprehensive rehabilitative initiatives for the hearing-disabled are recommended to reduce the hearing loss rates.  相似文献   
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90.
This article describes the operative technique that my colleagues and I apply to total mesorectal excision in patients with rectal cancer. A body of data support improvement of short-term outcomes over open resection. Although long-term data remain scarce, several ongoing trials may clarify this deficiency. The appropriateness of laparoscopy in the treatment for rectal cancer should be carefully weighed with consideration of patient preferences, surgeon experience, and available infrastructure.  相似文献   
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