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111.
Malignant triton tumor (MTT) is an aggressive peripheral nerve sheath tumor with rhabdomyoblastic differentiation. Less than 100 cases have been described, being mostly male children with type 1 neurofibromatosis. We report a 6‐year‐old female with MTT and no diagnostic criteria for neurofibromatosis type 1. Cytogenetic analysis showed a 46,X,‐X[4]/46,XX[16] karyotype. She underwent a transfemoral amputation and chemotherapy and is free of disease 15 months after diagnosis. The few cytogenetic studies of MTT described in the literature have been inconclusive. Further cytogenetic analyses are needed to understand the role of chromosome X monosomy in the pathogenesis of this rare tumor. Pediatr Blood Cancer 2012; 59: 1320–1323. © 2012 Wiley Periodicals, Inc.  相似文献   
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Microtexturing of implant surfaces is of major relevance in the endeavor to improve biorelevant implant designs. In order to elucidate the role of biomaterial’s topography on cell physiology, obtaining quantitative correlations between cellular behavior and distinct microarchitectural properties is in great demand. Until now, the microscopically observed reorganization of the cytoskeleton on structured biomaterials has been difficult to convert into data. We used geometrically microtextured silicon-titanium arrays as a model system. Samples were prepared by deep reactive-ion etching of silicon wafers, resulting in rectangular grooves (width and height: 2 µm) and cubic pillars (pillar dimensions: 2 × 2 × 5 and 5 × 5 × 5 µm); finally sputter-coated with 100 nm titanium. We focused on the morphometric analysis of MG-63 osteoblasts, including a quantification of the actin cytoskeleton. By means of our novel software FilaQuant, especially developed for automatic actin filament recognition, we were first able to quantify the alterations of the actin network dependent on the microtexture of a material surface. The cells’ actin fibers were significantly reduced in length on the pillared surfaces versus the grooved array (4–5 fold) and completely reorganized on the micropillars, but without altering the orientation of cells. Our morpho-functional approach opens new possibilities for the data correlation of cell-material interactions.  相似文献   
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Editor's choice     
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To determine whether nonhuman primates are infected with influenza viruses in nature, we conducted serologic and swab studies among macaques from several parts of the world. Our detection of influenza virus and antibodies to influenza virus raises questions about the role of nonhuman primates in the ecology of influenza.  相似文献   
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Patients with neuromuscular disorders often present with swallowing difficulties due to oral phase problems and pharyngeal residue after swallow. It is important to assess the underlying pathology and cause of the swallowing disturbance in this patient group, such as dystrophic changes in oral and masticatory muscles. This allows for more patient‐tailored recommendations, for example optimal compensation strategies to maintain function for longer. Ultrasound can show structural changes caused by dystrophy or denervation of muscles, detect involuntary movements such as fasciculations, and provide dynamic video images of tongue motion during swallowing attempts. This article, based on the authors' extensive experience with ultrasound in neuromuscular disease, explains the concepts of oral muscle ultrasound and its proven value in assessing neuromuscular mastication and swallowing problems. As a patient‐friendly and portable technique, we advocate its use as a standard tool for analyzing neuromuscular dysphagia. Clin. Anat. 30:183–193, 2017. © 2017 Wiley Periodicals, Inc.  相似文献   
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Electromagnetic navigation during flexible bronchoscopy   总被引:5,自引:0,他引:5  
BACKGROUND: Flexible bronchoscopy is routinely utilized in the diagnosis and treatment of various lung diseases. Nondiagnostic bronchoscopy leads to more invasive interventions, such as transthoracic needle aspiration, mediastinoscopy or even thoracotomy. Electromagnetic navigation is a novel technology that facilitates approaching peripheral lung lesions, which are difficult to sample by conventional means. The navigation system involves creating an electromagnetic field around the chest and localizing an endoscopic tool using a microsensor overlaid upon previously acquired CT images. OBJECTIVES: To determine the practicality, accuracy and safety of real-time electromagnetic navigation, coupled with previously acquired 3D CT images, in locating artificially created peripheral lung lesions in a swine model. METHODS: Peripheral lung lesions were created in four swine models by insertion of a metal tube (1 x 10 mm) via a transthoracic approach. An electromagnetic field was created by placing the animal on an electromagnetic location board. A position sensor incorporated into the distal tip of a dedicated tool was used to navigate to the various target lesions. Information gathered in real time during bronchoscopy was presented on a monitor simultaneously by displaying previously acquired CT images. Upon reaching the target lesion, biopsies were performed and the functionality and safety of the superDimension/Bronchus System was observed and documented. RESULTS: The registration accuracy expressed by the fiducial target registration error, expressing both the registration quality and the stability of fiducial (registration) points, was 4.5 mm on average. No adverse effects, such as pneumothorax or internal bleeding, were encountered in any of the animals in this study. CONCLUSIONS: Real-time electromagnetic positioning technology coupled with previously acquired CT images is an accurate technology added to standard bronchoscopy to assist in reaching peripheral lung lesions and performing biopsies.  相似文献   
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