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91.
From August 1984 to August 1987 at the Mayo Clinic, 226 computer-assisted stereotactic resections based on computed tomography or magnetic resonance imaging (or both) were performed on 203 supratentorial and 23 infratentorial lesions in various deep-seated or essential brain locations. Histologic examination revealed 112 glial neoplasms, 70 nonglial tumors, and 44 nonneoplastic lesions. The overall morbidity was 9.3% (21 of 226 patients were worse after the procedure), and the 30-day operative mortality was 1% (2 patients). The procedure provides maximal cytoreduction in high-grade glial neoplasms but is most beneficial to patients who have histologically circumscribed tumors, such as pilocytic astrocytomas, metastatic neoplasms, and miscellaneous nonglial and nonneoplastic lesions.  相似文献   
92.
This study assessed factors which may contribute to suboptimal image quality when the modified in vivo erythrocyte labeling technique is used with standard clinical 99mTc activities. For each assessment duplicate or triplicate blood specimens were withdrawn from > or = 10 patients, into syringes containing 700-900 MBq 99mTc as pertechnetate. After incubation the percent of 99mTc which was not bound to erythrocytes at blood re-injection time (%Unbound 99mTc), was measured and compared when one of four factors was varied. The most significant results, in descending order of measured effect were: [table: see text] Our data suggest that the requirements for optimal erythrocyte labeling with standard clinical 99mTc activities are: (A) Erythrocyte tinning time between 10 and 30 min; (B) blood volume > or = 3 ml; (C) blood incubation time > or = 20 min; and (D) Generator ingrowth time < or = 24 hr.  相似文献   
93.
An 11-year-old girl presenting with right upper quadrant abdominal pain was found to have a venous hemangioma of the posterior wall of the gallbladder. Radiographic, ultrasonographic, and angiographic findings of this entity, along with a review of the literature, are presented.  相似文献   
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95.
An animal model of chronic tympanic membrane perforation.   总被引:6,自引:0,他引:6  
Previous investigations into the healing and reconstruction of tympanic membrane (TM) perforations have involved animal models with acute TM perforations. A problem with the acute TM perforation model is that most acute TM perforations will heal spontaneously, both in animals and human beings. A second inadequacy of acute perforation models is that they are not analogous to the salient problem in human beings: long-standing TM perforation. The ideal animal model must have a TM perforation that is permanent, well-epithelialized, and free from infection. The perforation must also be subtotal to preserve a rim of membrane for experimental manipulations. In the chinchilla, we have identified a hardy animal with a short, wide ear canal and relatively large tympanic membranes. Thermal myringectomy, followed by medial infolding of TM microflaps, has resulted in permanent, subtotal chronic TM perforations in the chinchilla animal model. Of the 19 chinchillas (38 TMs) perforated, chronic subtotal perforations were created in 32 ears, 6 to 8 weeks after the initial procedure (84% success). Persistent infection or TM regeneration despite reperforation was recorded in 6 ears (16%) failure). This model is currently being used to assess various biomembrane scaffolds impregnated with growth-promoting substances in the regeneration of a physiologically sound TM, initially in our animal model and then in human beings. We envision the development of a biomembrane disc impregnated with biorecombinant growth factors that may provide a simple office technique for the repair of chronic, non-infected TM perforations.  相似文献   
96.
Carcinoid tumors and inflammatory bowel disease.   总被引:2,自引:0,他引:2  
Three cases are described in which carcinoid tumors arose in previously established inflammatory bowel disease: two were in the ileum in cases of Crohn's disease, and one was in the rectum in a case of ulcerative colitis. Review of this association in the literature suggests that it may be more than fortuitous.  相似文献   
97.
A 79-year-old man with a history of deep vein thrombosis and pulmonary embolism received anticoagulation therapy with warfarin 5 mg daily for 8 months. He was diagnosed with osteomyelitis and underwent partial metatarsal resection of his right foot. After surgery, antibiotics were initiated including ertapenem sodium 1 g intravenously every 24 hours, vancomycin 1400 mg intravenously every 24 hours, and rifampin 300 mg by mouth twice daily. Achieving a therapeutic level of anticoagulation was difficult despite escalating doses of warfarin, because of the interaction with rifampin. A 5- to 6-fold increase in warfarin dose was prescribed to reach therapeutic international normalized ratios (INRs), but even these increases were insufficient to maintain his INR in the therapeutic range. After rifampin was discontinued, warfarin doses were gradually reduced over the next 2 months. When concurrent warfarin-rifampin therapy is necessary, vigilant monitoring is imperative and significant increases in warfarin doses are likely.  相似文献   
98.
99.
Changing economic, political, environmental, and social conditions continue to have a cumulative impact on Australian regional communities, and in many instances, rural communities are being forced to initiate their own strategies in order to remain economically and socially viable. However, while communities respond in differing ways to similar change events, as do individuals, research examining the change process has largely been undertaken at the individual level. This article reports on an investigation of the characteristics that moderate a community's ability to manage change and the types of collective coping strategies communities employ to deal with change events. A model of community change process was used as the framework to examine the links between community characteristics, appraisal of change events (forest restructuring and tourism), and the use of collective strategies in three communities in Western Australia. Findings suggest that a community's mobilization of strategies is dependent on the collective assessment of the change event, the nature of the event, and the characteristics of the community. The implications for intervention through policy and community development are discussed briefly. © 2004 Wiley Periodicals, Inc. J Comm Psychol 32: 201–216, 2004.  相似文献   
100.
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