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995.
Murayama Y Viñuela F Suzuki Y Akiba Y Ulihoa A Duckwiler GR Gobin YP Vinters HV Iwaki M Abe T 《AJNR. American journal of neuroradiology》1999,20(10):1992-1999
BACKGROUND AND PURPOSE: Ion implantation is a surface-modification technology that creates a borderless surface on protein-coated platinum; this change in physical and chemical properties on the surface of Guglielmi detachable coils (GDCs) appears to enhance cell proliferation and adhesion. Our purpose was to evaluate the effect of ion implantation on GDCs in an experimental aneurysm model. METHODS: GDCs were coated with either type I collagen, fibronectin, vitronectin, laminin, or fibrinogen. Using He+ or Ne+ 1 x 10(14-15) ions/cm2, ion implantation was performed on these protein-coated GDCs (GDC-Is). A total of 56 experimental aneurysms were constructed microsurgically in the common carotid arteries of 28 swine. These experimental aneurysms were embolized with standard GDCs (n = 23), collagen GDC-Is (n = 11), vitronectin GDC-Is (n = 6), laminin GDC-Is (n = 4), fibrinogen GDC-Is (n = 6), and fibronectin GDC-Is (n = 6). The animals were sacrificed at day 14 after coil embolization. The physical properties of the new coils (friction on delivery, deployment into aneurysms, trackability, etc) and the development of tissue scarring and neoendothelium across the aneurysm's orifice were evaluated macroscopically and microscopically. RESULTS: No evidence of increased coil friction/stiffness was observed during delivery of GDC-Is through microcatheters in this aneurysm model. A more intense scar formation and neoendothelium at the neck of aneurysms were observed macroscopically when treated with GDC-Is. Significant differences in the proportion of neck coverage between standard GDCs (48.3% +/- 20.5%) and all GDC-I groups were observed (collagen GDC-I-89.4% +/- 14.9%, P < .01; vitronectin GDC-I-71.5% +/- 7.0%, P < .05; laminin GDC-I-76.5% +/- 11.0%, P < .05; fibrinogen GDC-I-74.8% +/- 13.9%, P < .05; fibronectin GDC-I-87.5% +/- 15.0%, P < .01). Light microscopy showed a well-organized fibrous tissue bridging the aneurysm's neck when using GDC-Is, whereas only a fibrin-like thin layer covered the standard GDC surfaces. CONCLUSION: GDC-Is indicated a more intense inflammatory response in the aneurysm body and dome and faster re-endothelial coverage of the neck of the aneurysm. This accelerated histologic response may decrease the chances of coil compaction and aneurysm recanalization. This technology may improve anatomic and clinical outcomes in patients harboring intracranial aneurysms. 相似文献
996.
Soto-Hernández JL Morales VA Lara Giron JC Balderrama Bañares J 《Clinical imaging》1999,23(4):209-214
Actinomycosis is an uncommon cause of intracranial infection. Epidural empyema represents about 6% of CNS actinomycotic lesions. A case of an epidural empyema with parietal bone osteomyelitis caused by Actinomyces israelii is presented. Relevant neuroimaging features were bone erosions and a multiloculated collection with annular contrast enhancing on CT. Postoperative MRI revealed extensive involvement of the neighbor dura, falx, and subdural space. MRI was crucial to follow-up the response to antibiotic treatment. 相似文献
997.
尾部悬吊及恢复过程中大鼠动脉血管收缩反应的变化 总被引:2,自引:2,他引:0
目的 探讨模拟失重下动脉收缩反应变化的时程特征及其可逆性。方法 采用尾部悬吊大鼠模型模拟失重,利用离休动脉环测定血管收缩反应的变化。结果 尾部悬吊2wk后,大鼠的腹主动脉、肠系膜动脉和股动脉收缩反应明显降低,而颈总动脉无明显改变;悬吊4wk后,肠系膜动脉和股动脉的收缩反应与悬吊2wk相比有进一步的降低;悬吊8wk大鼠的动脉血管收缩反应性与悬吊4wk相比无明显差异;4wk尾部悬吊大鼠解除悬吊后5wk 相似文献
998.
模拟失重大鼠比目鱼肌小动脉风各级血管内径的变化 总被引:1,自引:1,他引:0
目的 探讨模拟失重是否可引起后肢肌肉小动脉网各级血管内径发生改变及其可逆性。方法 采用墨汁灌注法观察尾部悬吊4wk(SUS-4),悬吊4wk后恢复1wk(REC-1)、恢复5wk(REC-5),以及对照(CON)大鼠比目鱼肌小动脉网各组血管内径的变化。结果 在SUS-4组,比目鱼肌的营养动脉、弓状小动脉及V、Ⅱ级模行小动脉的内径,较CON组分别减小了31%、29%、28%及41%(均为P〈0.01 相似文献
999.
轻、中度缺氧对事件相关电位的影响及不同刺激模式的比较 总被引:1,自引:1,他引:0
目的 观察轻、中度缺氧对脑事件相关电位(ERP)的影响,比较不同刺激模式发的ERP对缺氧的敏感性,方法12名受试者在地面、2500m和4300m匠心同度(吸放低氧混合气)分别进行视觉Ocddball、Sternberg记忆量(MSET)为1 和MSET为3的任务测试,记录ERP的P3潜伏期、波幅和反应时(RT)及反应错误率(ER)。结果 4300m高度缺氧时P3潜伏期显著延长,任务难度较大时ER增 相似文献
1000.
Qian Z Maynar M Usón-Garallo J Sanchez-Margallo F Lima-Rodriguez MA Lima-Rodrigues JR Kim JK Gonzalez-Roman A Castañeda WR 《Academic radiology》1999,6(5):317-320
RATIONALE AND OBJECTIVES: The purpose of the study was to evaluate a method of producing obstruction of the common bile duct and concomitant biliary duct dilatation in an animal model. MATERIALS AND METHODS: Laparoscopic placement of a double-balloon occlusion device was used to produce common bile duct obstruction and bile duct dilatation in pigs. RESULTS: One week after the procedure, common bile duct obstruction and dilatation of the biliary tree were demonstrated with either percutaneous transhepatic cholangiography or percutaneous cholecystography. CONCLUSION: The use of this method is technically feasible and provides a useful subacute and chronic animal model of common bile duct obstruction and dilatation of the biliary tree for percutaneous interventional training and research purposes. 相似文献