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91.
Increased reactive oxygen species in familial amyotrophic lateral sclerosis with mutations in SOD1 总被引:1,自引:0,他引:1
Said Ahmed M Hung WY Zu JS Hockberger P Siddique T 《Journal of the neurological sciences》2000,176(2):88-94
Amyotrophic lateral sclerosis (ALS) is a paralytic disorder characterized by degeneration of large motor neurons of the brain and spinal cord. A subset of ALS is inherited (familial ALS, FALS) and is associated with more than 70 different mutations in the SOD1 gene. Here we report that lymphoblast cell lines derived from FALS patients with 16 different mutations in SOD1 gene exhibit significant increase of intracellular reactive oxygen species (ROS) compared with sporadic ALS (SALS) and normal controls (spouses of ALS patients). The ROS generation did not correlate with SOD1 activity. Further, cells incubated with vitamin C, catalase or the flavinoid quercetin significantly reduced ROS in all groups. The catalase inhibitor 3-amino-1,2,4-triazole resulted in a ten-fold increase of ROS in all groups. Neither L-nitroarginine, a nitric oxide synthase inhibitor or vitamin E altered the ROS levels. Thus, these studies suggest that hydrogen peroxide (H(2)O(2)) is a major ROS elevated in FALS lymphoblasts and it may contribute to the degeneration of susceptible cells. Further, we postulate a mechanism by which increased H(2)O(2) could be generated by mutant SOD1. 相似文献
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PURPOSE: We report our 4-year experience with deep dorsal vein arterialization at 3 years' follow-up in young patients with pure cavernoocclusive dysfunction as an alternative to penile prosthesis implantation. MATERIALS AND METHODS: We performed a modified Furlow-Fisher operation (circumflex collaterals are preserved and the deep dorsal venous valves are not disrupted by a stipper) in 25 patients who did not have risk factors such as general arteriosclerosis, coronary heart disease, hypertension, hyperlipidemia and age (over 40 years). Patients with arterial disease diagnosed by Doppler examination were excluded from the study. Also, patients with abnormal penile biothesiometric and electromyographic findings were not included in the study. Beside the subjective and objective evaluation the efficacy of the operation was also assessed retrospectively in 18 patients by telephone according to items 3 (ability to achieve an erection) and 4 (ability to maintain an erection) of the 15-item International Index of Erectile Function (IIEF). RESULTS: With a mean follow-up of 28 months (range 4-42) subjective and objective success rates were 80 and 72% at 1 year's 75 and 62.5% at 2 years', and 70 and 60% at 3 years' follow-up. According to items 3 and 4 of the 15 item IIEF questionnaire the mean postoperative scores reached 1.55-3.44 and 1. 33-3.27 for items 3 and 4, respectively (p<0.01). Two patients (8%) showed signs of glans hypervascularization as a major complication and minor complications such as penile skin edema, subdermal hematoma, loss of penile skin sensation and early thrombosis of the anastomosis were found in a total of 8 patients (32%). CONCLUSIONS: Deep dorsal vein arterialization is a preferable choice in highly selected young patients as an alternative to penile prosthesis. 相似文献
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1 BACKGROUNDTheincidenceofCPis 0 .7per 1 0 0 0livebirths[1 ] .Becausecerebralpalsyinfluencesthewaychildrendevelop,itoftenresultsindevelop mentaldisability .Today ,more peoplehavecerebralpalsythananyotherdevelopmentaldis ability ,includingDownsyndrome,epilepsy ,andautism .Accordingtoasurveyconductedin1 986,2 .6%ofthepopulationofPakistaniaredisabled (includingbothphysicalandmentaldis abilities) .Childrenbetween 0~1 4 yearsinageconstitute 40 %ofthedisabled populationinPakistan .Routineme… 相似文献
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Sur RK Nayler S Ahmed SN Donde B Uijs RR Cooper K Giraud A 《South African journal of surgery. Suid-Afrikaanse tydskrif vir chirurgie》2000,38(1):13-16
Files of 8 patients with primary angiosarcomas treated in the Department of Radiation Oncology at the University of the Witwatersrand from 1982 to 1995 were identified. None of these patients had received prior radiotherapy or chemotherapy which would have predisposed them to the formation of an angiosarcoma. Slides of 6 patients were reviewed. Five of the 6 were confirmed as having angiosarcomas, while 1 patient was found to have a peripheral neuro-epithelial tumour. Four patients had angiosarcomas of the breast, while there was 1 patient each with angiosarcoma of the skin, intestine and brain. Complete excision was the primary modality of management whenever possible. Postoperative radiotherapy was given in cases of incomplete excision, patient refusal of radical surgery or gross tumour. Four patients died within 4 months of diagnosis. Three patients are alive (2 with no evidence of disease) 22-96 months after diagnosis. In 1 patient follow-up details were not available as he did not return for treatment. Angiosarcomas are aggressive malignant tumours arising from the endothelial cells. Complete surgical excision is the treatment of choice in the management of this aggressive disease, which has a poor prognosis. 相似文献
97.
Implications: We report a case of a patient who developed membranous tracheal disruption after severe vomiting. He subsequently required urgent colectomy for toxic megacolon under general anesthesia. With this challenging situation, we were able to successfully conduct general anesthesia in the presence of tracheal laceration, pneumothorax, and pneumomediastinum. 相似文献
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