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排序方式: 共有741条查询结果,搜索用时 15 毫秒
1.
Cellular blue nevus ("melanocytoma") of the spinal meninges: electron microscopic and immunohistochemical features 总被引:2,自引:0,他引:2
A primary cellular blue nevus (melanocytoma) of the spinal canal in a 21-year-old woman is reported. Light microscopic examination revealed a melanotic neoplasm with histological patterns resembling schwannoma, dermal nevi, and neuroblastic-like tumor. The ultrastructural features of the neoplastic cells were similar to those in dermal blue nevi and melanomas. There was no evidence of arachnoidal cell differentiation. Immunohistochemistry revealed positive reactions for S-100 protein and neuron-specific enolase in many cells and no reactions for glial fibrillary acidic protein, cytokeratins, epithelial membrane antigen, 70-kD neurofilament protein, or Leu-7. Vimentin was strongly positive in the melanocytic cells as well as in the arachnoidal cells of involved meninges. The ultrastructural and immunohistochemical features support the nevoid nature of this tumor, which is frequently mislabeled as "melanotic meningioma." 相似文献
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Lumbar radiculopathy secondary to gouty tophi in the filum terminale in a patient without systemic gout: case report 总被引:1,自引:0,他引:1
OBJECTIVE AND IMPORTANCE: Gouty arthritis and gouty tophi of the spine are very rare. We present a patient with the clinical manifestations of an intradural tumor and histologically proven gouty deposits in the filum terminale. CLINICAL PRESENTATION: The patient presented with typical symptoms of lumbar radiculopathy and neurogenic claudication. There was no evidence of peripheral gout. INTERVENTION: Imaging studies, including computed tomography and magnetic resonance imaging, demonstrated a 1-cm, round, intradural, calcified lesion at the L3 vertebral level, causing moderate spinal stenosis. The patient underwent a two-level laminectomy and removal of the mass. A pathological examination of the specimen revealed gouty deposits in the region of the filum terminale. CONCLUSION: Spinal involvement in gout is very rare, and intradural gouty deposits have not been previously described. Intradural gout should be considered in the differential diagnosis of intradural masses. 相似文献
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R. E. Garner R. G. Arim D. E. Kohen L. M. Lach M. J. MacKenzie J. C. Brehaut P. L. Rosenbaum 《Child: care, health and development》2013,39(3):412-421
Background Parenting behaviours influence child well‐being and development. However, much of the research on parenting behaviours and their correlates has focused on caregivers of healthy, typically developing children. Relatively less is known about the parenting behaviours of caregivers of children with chronic health conditions. Objective To examine and compare three parenting behaviours (positive interactions, consistency and ineffective parenting) among caregivers of children with neurodevelopmental disorders and/or externalizing behaviour problems, before and after accounting for child and family socio‐demographic characteristics. Methods Participants (n= 14 226) were drawn from the National Longitudinal Survey of Children and Youth, a long‐term study of Canadian children that follows their development and well‐being from birth to early adulthood. Children (and their caregivers) were divided into four groups according to the presence of a neurodevelopmental disorder (NDD; n= 815), the presence of an externalizing behaviour problem (EBP; n= 1322), the presence of both conditions (BOTH; n= 452) or neither of these conditions (NEITHER; n= 11 376). Results Caregivers of children in the NEITHER group reported significantly higher positive interaction scores and lower ineffective parenting behaviours than caregivers of children in any of the other three groups. Caregivers of children in the EBP and BOTH groups reported similar levels of consistency, but significantly lower levels than caregivers of NDD or NEITHER children. These associations largely remained after accounting for child and family socio‐demographic characteristics, with two exceptions: caregivers' reports of positive interactions were no longer significantly associated with child's NDD and BOTH conditions. Conclusions Parenting children with multiple health conditions can be associated with less positive, less consistent and more ineffective parenting behaviours. Understanding the factors that are associated with the challenges of caring for these children may require additional research attention. 相似文献
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Jan Marcin Węsławski Lucyna Kryla-Straszewska Jan Warzocha Jacek Urbański Maria Włodarska-Kowalczuk Lech Kotwicki 《Oceanological and hydrobiological studies.》2013,42(3):289-295
Extensive sampling (450 grabs) was performed all over the inner part of Puck Bay (105 km2 area) in summers of 2007–2009. The GIS-based analysis of samples was performed to assess in detail the distribution of 32 benthic species. The minimum area of occurrence was less than 1 km2 for Lekanosphaera rugicauda and the maximum was 83 km2 for Cerastoderma glaucum. The material reveals that species with the pelagic larval stage were most widespread, with the least distance between individuals and the highest average density (e.g. Cerastoderma glaucum, Hydrobia ventrosa). The most isolated and the least dense species within the studied area were discretely mobile, non-larval crustaceans (e.g. Gammarus oceanicus and Lekanosphaera rugicauda), present at single sites with the largest distance from each other. We conclude that analysis of species distribution helps in understanding the threats to populations of marine invertebrates and marine spatial planning, through locating the isolated species and populations. 相似文献
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Sworczak K Babńiska A Stanek A Lewczuk A Siekierska-Hellmann M Błaut K Drobińska A Basiński A Lachński AJ Czaplińska-Kałas H Gruca Z 《Neoplasma》2001,48(3):221-226
Clinically silent adrenal masses (incidentaloma) are incidentally discovered lesions, when noninvasive imaging methods (USG, CT, MRI) are performed for reasons other than known or suspected adrenal disease. Most studies report on a prevalence of adrenal incidentaloma range between 1% and 10% in radiological series. Between 1994 and 1999 we observed in our Department 57 patients with incidentalomas of adrenal glands. After endocrinological evaluation silent Cushing's syndrome was found in 2 cases (3.5%). Fifty two patients were qualified for surgery. Adrenocortical adenoma was diagnosed in 73.1%; adrenocortical carcinoma in 7.7%; pheochromocytoma in 7.7% and less frequent adrenal lesions in 11.5%. All adrenal carcinomas and malignant pheochromocytomas (11.5%) were found in tumors with diameter over 4 cm. 相似文献