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1.
Spitz tumours comprise a spectrum of melanocytic proliferations that share a set of distinct cytological features and molecular pathways. They include benign naevi, intermediate or indeterminate tumours and rare melanomas. Spitz tumours are notorious for the difficulty of distinguishing benign neoplasms with atypical features from melanomas and the related diagnostic uncertainty. Advances in the knowledge of the molecular pathways and genomic aberrations associated with these neoplasms have permitted opportunities for a reduction in the number of uncertain diagnoses and a more objective distinction between Spitz tumours from Spitz-like neoplasms. The presence of a Spitz molecular pathway, such as Harvey rat sarcoma viral oncogene homologue (HRAS) aberrations or kinase fusions, distinguishes a bona fide Spitz neoplasm from Spitz-like naevi or melanomas with conventional driver mutations. Spitz neoplasms with benign histopathological features and, if such testing is performed, benign cytogenetic and molecular findings, are termed Spitz naevi. Spitz neoplasms with frankly malignant histopathological findings or ambiguous microscopic findings associated with genetic or genomic aberrations most in keeping with melanoma are designated as Spitz melanoma. Tumours with microscopic features and genetic/genomic aberrations in between naevi and melanomas are classified as Spitz melanocytoma. 相似文献
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Josh Greenstein Devjani Das Josie Acuna Monica Kapoor Cara Brown Abbas Husain Brendan Lally Barry Hahn 《The American journal of emergency medicine》2019,37(2):313-316
Background
In the emergency department, rib fractures are a common finding in patients who sustain chest trauma. Rib fractures may be a sign of significant, underlying pathology, especially in the elderly patients where rib fractures are associated with significant morbidity and mortality. To date, no studies have evaluated the ability of ultrasound to detect rib fractures using cadaver models and subsequently use this model as a teaching tool.Objectives
The purpose of this study was to determine if it is possible to generate rib fractures on cadaver models which could be accurately identified using ultrasound.Methods
This was a cross-sectional study performed during one session at a cadaver lab. A single hemithorax from four adult cadavers were used as models. Single rib fractures on each of rib five through eight were created. Four subjects, blinded to the normal versus fractured ribs, were asked to identify the presence of a fracture on each rib.Results
A total of 8 of 16 potential ribs had fractured induced by study staff. Mean accuracy was 55% for all subjects. The overall sensitivity and specificity for detecting rib fractures was 50% (CI: 31.89–68.11) and 59.38% (CI: 35.69–73.55) respectively. The overall PPV and NPV was 55.17% and 54.29% respectively.Conclusions
In this pilot study, subjects were not able to detect induced rib fractures using ultrasound on cadaver models. The use of this model as a teaching tool in the detection of rib fractures requires further investigation. 相似文献3.
Karyopherin Alpha 2 Is an Adverse Prognostic Factor in Clear-Cell and Papillary Renal-Cell Carcinoma
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Clemens Drenowatz Klaus Greier 《Scandinavian journal of medicine & science in sports》2019,29(6):854-861
The beneficial associations of physical activity (PA) and sports with motor competence have been well documented. Similarly, high media time has been associated with poor motor competence. Limited information, however, is available on the combined effects of sport participation and media consumption on motor competence. The present study followed 213 Austrian middle‐school students (57% male; age at baseline: 10.4 ± 0.6 years) over a 4‐year period. Annual assessments included the German Motor Test 6‐18, along with self‐reported participation in club sports, time spent watching TV and using the computer. There were no interaction effects between sports participation and media time on motor competence. Club sports participation, however, was associated with higher motor competence, while there was an inverse association between media time and motor competence. Further, motor competence affected future participation in club sports while club sports had limited effects on subsequent motor development. High media time, on the other hand, impaired subsequent motor development, while effects of motor competence on media time were limited. Taken together, these results emphasize the importance of motor competence in the facilitation of sports participation during adolescence. Accordingly, a wide variety of movement experiences should be provided at young ages to promote motor development. In addition, the detrimental effects of media time on motor competence warrant that sedentary behaviors are targeted separately, particularly in youth not participating in sports. 相似文献
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Erika Cecon Anna Ivanova Marine Luka Florence Gbahou Anne Friederich Jean‐Luc Guillaume Patrick Keller Klaus Knoch Raise Ahmad Philippe Delagrange Michele Solimena Ralf Jockers 《Journal of pineal research》2019,66(2)
Melatonin receptors play important roles in the regulation of circadian and seasonal rhythms, sleep, retinal functions, the immune system, depression, and type 2 diabetes development. Melatonin receptors are approved drug targets for insomnia, non‐24‐hour sleep‐wake disorders, and major depressive disorders. In mammals, two melatonin receptors (MTRs) exist, MT1 and MT2, belonging to the G protein‐coupled receptor (GPCR) superfamily. Similar to most other GPCRs, reliable antibodies recognizing melatonin receptors proved to be difficult to obtain. Here, we describe the development of the first monoclonal antibodies (mABs) for mouse MT1 and MT2. Purified antibodies were extensively characterized for specific reactivity with mouse, rat, and human MT1 and MT2 by Western blot, immunoprecipitation, immunofluorescence, and proximity ligation assay. Several mABs were specific for either mouse MT1 or MT2. None of the mABs cross‐reacted with rat MTRs, and some were able to react with human MTRs. The specificity of the selected mABs was validated by immunofluorescence microscopy in three established locations (retina, suprachiasmatic nuclei, pituitary gland) for MTR expression in mice using MTR‐KO mice as control. MT2 expression was not detected in mouse insulinoma MIN6 cells or pancreatic beta‐cells. Collectively, we report the first monoclonal antibodies recognizing recombinant and native mouse melatonin receptors that will be valuable tools for future studies. 相似文献
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Xin Zhang Tim Zegar Tim Weiser Feda H. Hamdan Benedict-Tilman Berger Romain Lucas Dimitrios-IIias Balourdas Swetlana Ladigan Phyllis F. Cheung Sven-Thorsten Liffers Marija Trajkovic-Arsic Bjoern Scheffler Andreas C. Joerger Stephan A. Hahn Steven A. Johnsen Stefan Knapp Jens T. Siveke 《International journal of cancer. Journal international du cancer》2020,147(10):2847-2861