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101.
BACKGROUND: This study has been undertaken to investigate the possible alterations of oxidant/antioxidant status in uremic patients undergoing hemodialysis (HD) and the effects of vitamin E supplementation. METHODS: Erythrocyte antioxidant enzyme activities [glutathione peroxidase (GSHPx), superoxide dismutase (SOD) and catalase (CAT)] and thiobarbituric acid reactive substance (TBARS) concentrations as a measure of lipid peroxidation in HD patients have been determined and compared with healthy controls. The patient group consisted of 36 uremic patients 21-75 years of age undergoing maintenance HD three times weekly for an average of 41 months. The efficiency of Vitamin E therapy in dialysis patients was also assessed by re-evaluating antioxidant status of the same patients after supplementation of the vitamin E in a dosage of 600 mg/daily for 14 weeks. RESULTS: A significant decrease in the activities of erythrocyte SOD, CAT and GSHPx and a significant increase in TBARS concentrations were found in patient group compared to control group (p<0.001). A significant correlation between GSHPx activities and duration of HD therapy was also observed (r=-0.46, p<0.01). Vitamin E supplementation caused an increase in GSHPx and SOD activities and a decrease in TBARS concentrations. A slight but not significant increase in CAT activity was also observed by Vitamin E. CONCLUSIONS: The results suggest the presence of an oxidative activity and the possible preventive role of Vitamin E therapy in uremic patients undergoing HD.  相似文献   
102.
BACKGROUND AND PURPOSE: Various sedative and analgesic medication has been used for shockwave lithotripsy (SWL). The aim of this study was to evaluate the efficacy of different anesthesia modalities in these patients. PATIENTS AND METHODS: One hundred patients were randomly divided into four groups. The first (Group F) received fentanyl 1 microg/kg intravenously (IV), the second (Group D) received diclofenac sodium 1 mg/kg intramuscularly (IM), the third (Group T) received tramadol 1.5 mg/kg IM, and the fourth (Group E) was given 15 g of eutectic mixture local anesthetic (EMLA) cream containing lidocaine and prilocaine. After routine preoperative evaluation, all patients received midazolam 2 mg IV 5 minutes before lithotripsy for sedative premedication. In all groups, a supplemental 25-microg bolus of fentanyl was administered IV when patients complained of pain, moved, or grimaced in response to the shockwaves. Pain intensity was evaluated on a 0- to 100-mm visual analog scale (VAS). The level of sedation was determined using the Observer's Assessment of Alertness/Sedation (OAS/S). Side effects such as bradypnea, oxygen desaturation, bradycardia, pruritus, and nausea and vomiting were recorded. RESULTS: There were no statistically significant differences among the four groups with regard to VAS, OAS/S scores, or side effects. In Group F, the mean arterial pressure was decreased significantly at 10 and 20 minutes. The patients in this group also manifested a decrease of oxygen saturation at the first, tenth, and twentieth minutes and the end of SWL. CONCLUSION: Application of EMLA cream was as safe and effective as fentanyl, diclofenac, and tramadol, and reduction of the fentanyl dose during SWL was possible.  相似文献   
103.
Induction of colitis by acetic acid (AA) in the rat is widely used experimental model of inflammatory bowel disease (IBD) and ulcerations. AA as an irritant induces colitis involving infiltration of colonic mucosa with neutrophils and increased production of inflammatory mediators, such as hydrogen peroxide (H2O2), nitric oxide (NO), myeloperoxidase activity (MPO), and tumor necrosis factor (TNF-alpha). Trimetazidine (TMZ), an antianginal compound, was administered to investigate if its cytoprotective features in cardiac tissue are also effective in AA colitis where ischemic injury contributes to colitis. Administration of TMZ intraperitoneally improved the macroscopic and microscopic score alterations produced by AA. AA administration significantly elevated colonic MPO activity; however, treatment with TMZ significantly lowered this enzyme activity compared to AA. AA administration significantly enhanced superoxide dismutase (SOD) activities, except for AA + TMZ given rectally. TMZ treatment significantly lowered nitrate levels, but AA increased these levels. AA administration markedly lowered TNF-alpha levels, but TMZ treatment elevated these levels to control. These findings indicate that overproduction of NO may be involved in the immunosuppression observed during acute AA-induced rat colitis. In conclusion, TMZ treatment was more effective via the intraperitoneal than rectal route, and may be beneficial in therapy of colitis.  相似文献   
104.
A case of primary chondrosarcoma of the testis is reported. A 40-year-old man presented a painless swelling of the right testis that he has been observing for 3 years. Gross examination of the resected specimen showed an encapsulated, gray to tan colored, roughly rounded tumor. Histologically, the tumor revealed a well-differentiated chondrosarcoma.  相似文献   
105.
As part of our ongoing efforts to understand the fundamental nature of light scattering from cells and tissues, we present data on elastic light scattering from isolated mammalian tumor cells and nuclei. The contribution of scattering from internal structures and in particular from the nuclei was compared to scattering from whole cells. Roughly 55% of the elastic light scattering at high-angles (> 40 degrees) comes from intracellular structures. An upper limit of 40% on the fractional contribution of nuclei to scattering from cells in tissue was determined. Using cell suspensions isolated from monolayer cultures at different stages of growth, we have also found that scattering at angles greater than about 110 degrees was correlated with the DNA content of the cells. Based on model calculations and the relative size difference of nuclei from cells in different stages of growth, we argue that this difference in scattering results from changes in the internal structures of the nucleus. This interpretation is consistent with our estimate of 0.2 micron as the mean size of the scattering centers in cells. Additionally, we find that while scattering from the nucleus accounts for a majority of internal scattering, a significant portion must result from scattering off of cytoplasmic structures such as mitochondria.  相似文献   
106.
Activated recombinant factor VIIa was administered to a preterm infant with bleeding diasthesis and a huge subdural hematoma that could not be controlled by the blood products. The coagulation tests were normalized the following day. Recombinant factor VIIa can be a choice in selected cases with intractable bleedings unesponsive to conventional replacement therapy.  相似文献   
107.
108.

Purpose  

The effectiveness of carboplatin and vincristine chemotherapy in the treatment of low-grade glioma (LGG) is well established. However, carboplatin hypersensitivity reactions (CHR) are a major problem leading to premature cessation of therapy. We aimed to investigate the clinical features and the management strategies in CHR, retrospectively.  相似文献   
109.
OBJECTIVE: The purpose of this study was to evaluate the relationship between the quality of root canal fillings and type of permanent coronal restorations and their association with the periapical status in a Turkish subpopulation. STUDY DESIGN: There were 1268 endodontically treated teeth from 280 panoramic radiographs that were evaluated. Two observers assessed the radiographs using an x-ray viewer with 2 times magnification. Teeth were classified according to the type of restorations. The quality of root canal fillings were evaluated according to the criteria determined by Tronstad et al. Apical status was assessed by the Periapical Index scores (PAI) proposed by ?rstavik et al. Chi-square test was used for statistical analysis. RESULTS: There were 59.5% of endodontically treated teeth that showed healthy periapex. Teeth with good endodontic treatment showed statistically significant high healthy periapex rates regardless of the type of the restoration. In addition, the evaluation of the entire material also showed that the roots with posts had significantly more periapical pathosis than roots without posts (P = .001). CONCLUSIONS: It can be concluded that, although the quality of the root canal filling plays a key role in the outcome of endodontic therapy, the type of restoration can also be a contributing factor in the treatment outcome.  相似文献   
110.
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