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排序方式: 共有1139条查询结果,搜索用时 15 毫秒
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Perforated colorectal neoplasms: correlation of clinical, contrast enema, and CT examinations 总被引:2,自引:0,他引:2
Hulnick DH; Megibow AJ; Balthazar EJ; Gordon RB; Surapenini R; Bosniak MA 《Radiology》1987,164(3):611-615
Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm. 相似文献
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Regina F. Gandour-Edwards Paul J. Donald Philip J. Vogt Robert Munn Kyung-Whan Min 《Head & neck》1994,16(4):379-382
Background. Carcinosarcoma or true malignant mixed tumor of the parotid gland is extremely rare, accounting for <1% of all salivary gland malignancies. Methods. A 63-year-old woman presented with a 5-cm right parotid mass which was resected with a radical parotidectomy and infratemporal fossa dissection. Results. The tumor contained two distinctive histologic patterns, that of a poorly differentiated ductal carcinoma and a pleomorphic rhabdomyosarcoma. Additionally, a residual focus of pleomorphic adenoma was present peripherally, Immunohistochemical and electron microscopic studies confirmed the skeletal muscle differentiation. Conclusions. The pattern of combined rhabdomyosarcoma and ductal carcinoma has not been previously reported and adds further evidence to the myoepithelial derivation of these tumors. © 1994 John Wiley & Sons, Inc. 相似文献
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Coralline hydroxyapatite bone graft substitutes: preliminary report of radiographic evaluation 总被引:1,自引:0,他引:1
A new bone graft substitute made by conversion of the calcium carbonate exoskeleton of reef-building sea coral into hydroxyapatite has recently become clinically available. The normal radiographic appearance of two forms of this material is described. In the immediate postoperative period, the exoskeletal architecture of these implants is readily appreciated. With graft incorporation over the ensuing months, their intrinsic structure is gradually lost in association with poor marginal definition. Evolving radiographic findings reflect the biocompatible nature of these implants, which provides the potential for ingrowth of native bone with preservation of the coralline scaffold, resulting in enhanced biomechanical properties. 相似文献
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Retroperitoneal versus transperitoneal approach for repair of abdominal aortic aneurysms 总被引:1,自引:0,他引:1
G A Sicard B T Allen J S Munn C B Anderson 《The Surgical clinics of North America》1989,69(4):795-806
We, as well as other authors, believe that the retroperitoneal approach is an excellent alternative to the transperitoneal route for the repair of abdominal aortic aneurysms. This approach is associated with a significant decrease in pulmonary and cardiac complications and therefore can be used in selected high-risk patients with expanding aneurysms. A well-controlled randomized multicenter trial should answer the question: "Is this approach the surgical access of choice for the elective repair of abdominal aortic aneurysms?" 相似文献
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P. Michael Stuart Rita K. Munn Edward DeMoll Jerold G. Woodward 《Human immunology》1995,43(4):269-275
We reported that antigenic preparations from Yersinia enterocolitica stimulate murine T cells in a manner consistent with that of superantigens. As a consequence we examined whether Y. enterocolitica antigenic preparations stimulate human T-cell cultures. Human T cells, enriched from peripheral blood lymphocytes, were stimulated to proliferate in the presence of Y. Enterocolitica cytoplasmic and membrane preparations. This activity has also been shown to be sensitive to protease treatment, indicating the presence of a protein, and when separated by ion-exchange chromatography a single peak of activity is resolved. Furthermore, this proliferation was inhibited, in a dose-dependent manner, by the presence of antibodies directed against MHC class II antigens, indicating a requirement for these molecules. When these cells were stained with a panel of Vβ-specific antibodies to determine if there was an enrichment of a particular Vβ-bearing T-cell subset after stimulation, results indicate a significant enrichment of T cells bearing Vβ3, Vβl2, Vβl4, and Vβl7 over controls. Taken together, these data are consistent with a Y. enterocolitica product acting as a superantigen for human T cells. 相似文献