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排序方式: 共有3819条查询结果,搜索用时 15 毫秒
191.
Imaging of soft-tissue myxoma with emphasis on CT and MR and comparison of radiologic and pathologic findings 总被引:4,自引:0,他引:4
Murphey MD McRae GA Fanburg-Smith JC Temple HT Levine AM Aboulafia AJ 《Radiology》2002,225(1):215-224
PURPOSE: To determine the imaging characteristics of soft-tissue myxoma, with emphasis on computed tomographic (CT) and magnetic resonance (MR) imaging findings and pathologic comparison. MATERIALS AND METHODS: Records of 45 pathologically confirmed soft-tissue myxomas in 44 patients were retrospectively reviewed. Patient demographics and radiographs (n = 20), bone scintigrams (n = 2), angiograms (n = 3), and ultrasonographic (US) (n = 6), CT (n = 14), and MR images (n = 33) were evaluated by two musculoskeletal radiologists with agreement by consensus for lesion location, lesion size, and intrinsic characteristics. RESULTS: Soft-tissue myxoma more commonly affected women (59%; average age 52 years) and manifested as a slowly enlarging (64%) painful (51%) mass. Lesions were most frequently intramuscular (82%) and involved the thigh (51%). An appearance similar to that of a cyst was seen at CT (at which the lesions demonstrated low attenuation) and at MR imaging (at which the lesions demonstrated markedly high signal intensity on T2-weighted images) in all cases because of the high water content of mucin that was seen histologically. The true solid architecture of these lesions was best depicted in all cases at US (at which the lesions were hypoechoic, not anechoic) and on MR images obtained with contrast material (at which the lesions demonstrated internal enhancement). A small amount of tissue similar to fat surrounding these intramuscular myxomas (71% at MR imaging) corresponded histologically (70%) to atrophy of surrounding muscle. CONCLUSION: Soft-tissue myxoma often demonstrates characteristic US, CT, and MR imaging findings, including intramuscular location, intrinsic high water content, and a surrounding rim of fat. 相似文献
192.
Gina DelGiudice-Asch Lorraine Simon James Schmeidler Charlotte Cunningham-Rundles Eric Hollander 《Journal of autism and developmental disorders》2000,30(1):71-75
Letter to the Editor
Letters to the Editor 相似文献193.
PURPOSE: This study explored the effect of frequency (number of presentations), and spacing (period between presentations) on verb learning in children with specific language impairment (SLI). Children learn words more efficiently when presentations are frequent and appropriately spaced, and this study investigated whether children with SLI likewise benefit. Given that these children demonstrate greater frequency dependence and rapid forgetting of recently acquired words, an investigation of frequency and spacing in this population is especially warranted. METHOD: Twenty-four children with SLI (mean age 5;6 [years;months]) and 24 language-matched control children (mean age 3;4) were taught novel verbs during play sessions. In a repeated measures design, 4 experimental conditions combined frequency (12 or 18 presentations) and spacing (all presentations in 1 session, or spread over 4 days). Comprehension and production probes were administered after the final session and 1 week later. RESULTS: Although the children with SLI benefited significantly from frequent and widely spaced presentations, there were no significant effect in the control group. The language-impaired children showed rapid forgetting. CONCLUSIONS: The frequency and spacing of presentations crucially affect the verb learning of children with SLI. A training regimen characterized by appropriately spaced intervals and moderate repetition will optimally benefit lexical learning. 相似文献
194.
Cheryl Regehr Gina Dimitropoulos Elaine Bright Sharon George Joscelyn Henderson 《Family relations》2005,54(3):423-435
Abstract: Support of family is paramount to reducing the impact of highly stressful work on firefighters. Yet the degree of stress encountered by the family members, particularly spouses, resulting from ongoing job demands and exposure to traumatic situations is unclear. This qualitative study examined the effects of emergency service work on spouses of firefighters. While participants were highly supportive and proud of their spouse's work, they nevertheless encountered several challenges. Specific areas of challenge were (a) the effects of shift work on family life, (b) the transfer of firefighters’ reactions to dangerous and traumatic events to family, and (c) the social atmosphere associated with the fire service. Suggestions for the development of support services for firefighters and their families are offered. 相似文献
195.
Magnetic Resonance Imaging of Intramedullary Spinal Cord Tumors 总被引:4,自引:0,他引:4
Lowe GM 《Journal of neuro-oncology》2000,47(3):195-210
The advent of MRI has significantly changed the diagnosis of spinal cord tumors. Standard imaging provides excellent localization and characterization of the tumor in a noninvasive fashion. Exact histologic diagnosis of the two most common tumors, ependymoma and astrocytoma, remains elusive but there are some suggestive imaging characteristics. It is hoped that some of the newer MR imaging sequences will improve characterization of the tumor and thereby influence therapy. Several of these pulse sequences are already used routinely in brain imaging. Evaluation of new imaging sequences in the spine has lagged behind brain MR imaging, mainly due to technical factors. Work on animal spine models and extrapolation from brain imaging studies suggest that it is only a matter of time before some of these techniques become clinically relevant. 相似文献
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Tobacco is a heavily pesticide-dependent crop. Because pesticides involve human safety and health issues, they are regulated nationally and internationally; however, little is known about how tobacco companies respond to regulatory pressures regarding pesticides. In this study we analyzed internal tobacco industry documents to describe industry activities aimed at influencing pesticide regulations. We used a case study approach based on examination of approximately 2,000 internal company documents and 3,885 pages of U.S. Environmental Protection Agency documents obtained through Freedom of Information Act requests. The cases involved methoprene, the ethylene bisdithiocarbamates, and phosphine. We show how the tobacco industry successfully altered the outcome in two cases by hiring ex-agency scientists to write reports favorable to industry positions regarding pesticide regulations for national (U.S. Environmental Protection Agency) and international (World Health Organization) regulatory bodies. We also show how the industry worked to forestall tobacco pesticide regulation by attempting to self-regulate in Europe, and how Philip Morris encouraged a pesticide manufacturer to apply for higher tolerance levels in Malaysia and Europe while keeping tobacco industry interest a secret from government regulators. This study suggests that the tobacco industry is able to exert considerable influence over the pesticide regulatory process and that increased scrutiny of this process and protection of the public interest in pesticide regulation may be warranted. 相似文献
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Conditions that once were considered either relative or absolute contraindications for laparoscopic splenectomy have become fewer and less significant in the overall assessment of candidates for this procedure. Advances in surgical technique, operative conduct, and instrumentation have made it feasible to perform splenectomy laparoscopically with good outcomes and minimal morbidity in a variety of different pathologic conditions. Obesity, malignancy, pregnancy, and splenomegaly are assessed here in detail. 相似文献