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排序方式: 共有626条查询结果,搜索用时 15 毫秒
41.
Lleó Pérez A Hernández Pérez D Hernández Martínez FJ Navarro Palop C Marcos Jorge A Pallas Ventayol C 《Archivos de la Sociedad Espa?ola de Oftalmología》2000,75(8):555-558
PURPOSE/METHODS: Serpiginous choroiditis is a rare, chronic, progressive, and recurrent bilateral disorder primarily involving the choriocapillaris and the retinal pigment epithelium. Progression typically occurs as pseudopodia extensions away from the optic discs and usually infringes upon the macula and foveal region. RESULTS/CONCLUSIONS: We studied three cases of geographic choroidopathy, showing the ophthalmoscopic picture and the fluorescein angiographic of the fundus oculi, characterised by typical disease lesions. Finally, some considerations in differential diagnosis between pigment epithelium inflammatory diseases will be reported. 相似文献
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Wakefield MA Ruel EE Chaloupka FJ Slater SJ Kaufman NJ 《Journal of health communication》2002,7(2):113-121
The objective is to determine the relationship between brand-specific advertising and promotions in convenience stores for Marlboro and Camel cigarettes and choice of usual brand among school students. A cross-sectional survey was designed that merged records of store tobacco advertising and promotions. The survey was administered to 3,890 U.S. high school smokers with a usual brand, matched to 196 convenience stores. Choice of Marlboro as a usual brand was associated with presence of a Marlboro gift with purchase (p <.001) and a greater brand share of interior (p = .05) and exterior (p = .05) advertising voice for Marlboro. Choice of Camel as a usual brand was associated with a greater share of interior advertising voice for Camel (p <.001) but was unrelated to a Camel gift with purchase promotions (p > .05) and negatively associated with a greater share of exterior advertising voice for Camel (p < .001). The results are consistent with the notion that Marlboro-specific advertising and promotions may influence choice of Marlboro as a usual brand to smoke among teens, but resultsfor Camel are mixed and inconclusive. Further research is required to confirm and extend these findings. 相似文献
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The authors report a case in which the clinical and neuroimaging findings were initially considered diagnostic of a brainstem glioma. Angiography revealed a deep venous system (galenic) dural arteriovenous fistula causing brainstem interstitial edema. Successful endovascular surgery resulted in complete clinical recovery of the patient and resolution of the structural abnormalities that had been observed on magnetic resonance images. The neuroimaging and therapeutic significance of this case are discussed. 相似文献
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Dural arteriovenous fistulas 总被引:2,自引:0,他引:2
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Expression and function of VLA-alpha 2, -alpha 3, -alpha 5 and -alpha 6-integrin receptors in pancreatic carcinoma. 总被引:3,自引:0,他引:3
R J Weinel A Rosendahl K Neumann B Chaloupka D Erb M Rothmund S Santoso 《International journal of cancer. Journal international du cancer》1992,52(5):827-833
The expression of the VLA-integrins alpha 2, alpha 3, alpha 5 and alpha 6 was studied immunohistochemically in tissue samples from ductal pancreatic cancer, chronic pancreatitis, normal pancreas and in 8 cell lines of ductal human pancreatic cancer. Furthermore, adhesion assays on purified extracellular matrix (ECM)-compounds were used to define the function of alpha 2, alpha 3, alpha 5 and alpha 6 in pancreatic cancer cells. Immunohistochemically, VLA alpha 2 and VLA alpha 6 were moderately to strongly expressed on the basal surface of ductal and acinar cells in normal pancreatic tissue, while centro-acinar cells predominantly expressed VLA alpha 3 and VLA alpha 5. Pancreatic carcinoma showed intense staining for VLA alpha 2 and VLA alpha 6 with a diffuse distribution on the cell surface. The redistribution of VLA alpha 2 and VLA alpha 6 may reflect a loss of spatial arrangement of tumor cells and their ability to interact randomly with extracellular matrix structures during invasion and metastasis. Expression of VLA alpha 3 and VLA alpha 5 in pancreatic carcinoma was heterogeneous, ranging from moderate to weak, and was lost in about 50% of the cells. Two pancreatic carcinoma cell lines (PC 3, PC 44) were further investigated in adhesion assays. Monoclonal antibodies (MAbs) against alpha 2 (GI 9, 10-G-11) were able to inhibit tumor-cell adhesion to collagen IV (59%-72%) in both cell lines. A MAb against alpha 6 (GoH3) inhibited tumor-cell adhesion to laminin (52%-86%) in both cell lines. These results suggest that alpha 2 is a collagen-binding site and alpha 6 a laminin-binding site in pancreatic cancer cells. The anti-alpha 5-MAb SAM I inhibited adhesion of PC3 to fibronectin (76%), being without effect in PC44. Adhesion of both cell lines to fibronectin was almost completely inhibited by RGDS (85%-88%). Thus, alpha 5 is a functionally important fibronectin binding site in some pancreatic carcinoma cells, suggesting further RGD-dependent fibronectin binding sites in other pancreatic carcinoma cells. 相似文献
50.
J C Chaloupka F Viuela C Kimme-Smith J Robert G R Duckwiler 《AJNR. American journal of neuroradiology》1994,15(3):509
PURPOSETo conduct a validation study of a Doppler guide wire for potential neuroendovascular applications.METHODSA 12-MHz, 0.018-inch Doppler guide wire was evaluated in eight swine under various blood flow conditions using two types of in vivo cerebrovascular models (physiologic and arteriovenous shunting). Flow conditions were mechanically and pharmacologically altered. Doppler average peak velocity was compared with volumetric blood flow, and flow profile corrections were calculated and analyzed. Qualitative aspects of the Doppler guide wire spectra were also assessed.RESULTSPlots of average peak velocity versus volumetric blood flow showed excellent linear relationships (r2 > 0.94), which were maintained at high flow conditions (average peak velocity, 99 to 236 cm/sec; volumetric blood flow, 392 to 889 mL/min). Values of flow profile correction varied from 0.43 to 0.94 and showed no consistent relationship to changes in volumetric blood flow.CONCLUSIONSThe excellent correlation between average peak velocity and volumetric blood flow over a wide range of blood flow conditions and the additional qualitative information of the Doppler guide wire spectra establish a foundation for clinical implementation. The unpredictable variations of flow profile corrections remain obstacles for calculating volumetric blood flow based on Doppler guide wire average peak velocity. 相似文献