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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
992.
Effect of the free radical scavenger MCI-186 on spinal cord reperfusion after transient ischemia in the rabbit 总被引:4,自引:0,他引:4
Kenichi Hashizume Toshihiko Ueda Hideyuki Shimizu Atsuo Mori Ryohei Yozu 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(8):426-433
Objective: Paraplegia remains a serious complication of aortic operations. The production of free radicals during reperfusion
after transient ischemia is believed to induce secondary spinal neuronal injury, resulting in paraplegia. The aim of the present
study was to clarify the protective effect and method of administration of antioxidants on the neurological and histological
outcome in the animal model for reperfusion injury after transient spinal cord ischemia. Methods: New Zealand white rabbits underwent surgical exposure of the abdominal aorta that was clamped for 15 minutes to achieve spinal
cord ischemia. Group A animals received two 10 mg/kg doses of 3-methyl-l-phenyl-2-pyrazolin-5-one (MCI-186) at the time of
release of the aortic clamp and 30 minutes later. In group B, MCI-186, 5 mg/kg, was given three times, at the time of aorta
clamp release, 30 minutes and 12 hours later. In group C (control group), one dose of vehicle was administered. Neurological
status was assessed using modified Tarlov’s score until 168 hours after operation. Spinal cord sections were examined microscopically
to determine the extent of ischemic neuronal damage. Results: Groups A and B animals had better neurological function than group C (p(0.001). In contrast, group C animals exhibited paraplegia or paraparesis with marked neuronal necrosis. The number of surviving
neurons within examined sections of the spinal cord was significantly greater in group B than in group C (p(0.001). Conclusion: In a 15-minute ischemia-reperfusion model using rabbits, systemic repetitious administration of MCI-186, a free radical scavenger,
was found to have a protective effect on the spinal cord neurons both neurologically and histologically. We postulate that
the drug minimizes the delayed neuronal cell death for reperfusion injury after transient ischemia by reducing the free radical
molecules. Moreover, it was thought that we could protect delayed neuronal cell death more effectively by administering MCI-18612
hours later. 相似文献
993.
Derick T Wade 《British medical journal》2005,330(7489):468-471
994.
995.
A T Lee 《Aviation, space, and environmental medicine》1991,62(2):158-161
In-flight encounters with hazardous weather represent one of the most significant safety issues in civil aviation operations. Aircrew judgment is often cited as the probable cause of incidents and accidents involving weather, although lack of information is also a factor. The present study examines how information, presented at different times and in different forms, affects the awareness and decision-making behavior of aircrews in a flight simulation study of a recent microburst/windshear incident. In order to examine the influence of enhanced information transfer on aircrew behavior, intracrew communications and approach-to-land decisions were evaluated with conventional ATC communications and with automated cockpit alerting and display of weather information. Results of the study revealed that aircrews provided only with conventional ATC transmissions of weather information had difficulty discriminating conditions conducive to microburst events from less hazardous windshear events. Improved situation awareness for microburst events was found when ground-based convective weather information was provided in real time to aircrews. Avoidance decision-making was found to be less efficient with conventional ATC alert transmissions when compared to the performance of crews provided with a visual display of microburst events. The importance of information transfer on aircrew situation awareness and decision-making in hazardous weather avoidance is discussed. 相似文献
996.
997.
998.
999.
1000.
F Kaneoya K Yoshida S Horiuchi T Negishi 《Hinyokika kiyo. Acta urologica Japonica》1986,32(10):1505-1507
The presented report is fibrosarcoma arising from renal capsule in a 64-year-old woman. The tumor is very rare and is the 25th case in Japan. The patient visited our hospital with the complaint of macroscopic hematuria for several days. Abdominal examination revealed a painless lump from the left lumbar region to para-median abdomen. A diagnosis of hydronephrosis caused by neoplasma or tuberculosis was considered by CT, AG, etc., and transperitoneal nephrectomy was performed on 6-July-1984. Pathology of the tumor was fibrosarcoma arising from the renal capsule. Three months later, the tumor was growing on the peritoneal surface from the left renal region and she died on Nov. 10, 1984. 相似文献