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991.

Introduction

Ozone has been proposed as an antioxidant enzyme activator, immunomodulator and cellular metabolic activator. This study was designed to investigate the efficacy of ozone therapy in the prevention of esophageal damage and stricture formation developed after esophageal caustic injuries in the rat.

Materials and Methods

Forty-five rats were allocated into three groups; sham-operated, un-treatment and treatment groups. Caustic esophageal burn was created by instilling 15% NaOH in the distal esophagus. The rats were left untreated or treated with 1 mg/kg/day ozone intraperitoneally. All rats were sacrificed at 28 days. Efficacy of the treatment was assessed by measuring the stenosis index (SI) and histopathologic damage score, and biochemically by determining tissue hydroxyproline content (HP), superoxide dismutase (SOD), glutathione peroxidase (GPx), malondialdehyde (MDA) and protein carbonyl content (PCC) in esophageal homogenates.

Results

Whereas seven (47%) rats died in the un-treatment group, all rats in the sham-operated and the treatment group survived during the study. SI, the histopathologic damage score, was significantly lower in the ozone-therapy group than the un-treatment group. HP levels were significantly higher in the un-treatment group than the group treated with ozone. Caustic esophageal burn increased MDA and PCC levels and also decreased SOD and GPx enzyme activities. In contrast, ozone therapy decreased the elevated MDA and PCC levels and also increased the reduced SOD and GPx enzyme activities.

Conclusion

Ozone has a preventive effect in the development of fibrosis by decreasing tissue damage and increasing the antioxidant enzyme activity in an experimental model of corrosive esophageal injury.  相似文献   
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BACKGROUND: Left ventricular pseudoaneurysm is a rare and frequently fatal complication of acute myocardial infarction. It occurs as a consequence of rupture of the ventricular free wall that gets confined by a portion of the pericardium. The purpose of this study was to present our surgical experience of postinfarction left ventricular pseudoaneurysms and to evaluate mid-term results. METHODS: The study population comprised five symptomatic patients diagnosed with left ventricular pseudoaneurysm and treated surgically in a short period of time. There were three males and two females. The mean age of the patients was 66.8 +/- 10.8 years. The diagnosis was made initially by echocardiography and subsequently confirmed by angiography. An additional cardiac magnetic resonance imaging study was performed in three patients. Surgical resection of the pseudoaneurysm was combined with an endoaneurysmorrhaphy procedure in all patients. Associated cardiac operations were performed in three patients. Definitive diagnosis of pseudoaneurysm was confirmed by histopathological evaluation of the excised wall in all patients. RESULTS: All patients survived the operation and were discharged to home care. The mean duration of hospital stay was 11.6 +/- 4.6 days. Patients were either in class I or II of New York Heart Association classification at discharge. All patients are still being followed after surgery with a mean follow-up period of 10.4 +/- 6.6 months with no further problems. CONCLUSION: Surgical repair is indicated in left ventricular pseudoaneurysm as it carries a high risk of rupture and sudden cardiac death. Surgical repair combined with an endoaneurysmorrhaphy procedure carries a low mortality risk and improves functional capacity.  相似文献   
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BACKGROUND AND PURPOSE: We investigated the impact of percutaneous renal procedures on estimated glomerular filtration rate (GFR) of patients with chronic kidney disease (CKD). PATIENTS AND METHODS: The GFRs of adult patients were calculated using the Modification of Diet in Renal Disease formula, and the patients were staged according to the Kidney Disease Outcome Quality Initiative CKD classification system. The study included 185 patients with preoperative GFR values less than 60 mL/min/1.73 m(2). The impact of percutaneous nephrolithotomy (PCNL) on GFR was analyzed by comparing the preoperative GFR with the GFR before discharge and at postoperative month 3. RESULTS: Patients with CKD had a significant increase in the GFR after the procedure. In postoperative month 3, the mean GFR was more than 60 mL/min/1.73 m(2) in 25% of the patients with CKD and less than 60 mL/min/1.73 m(2) in 75%. While all patients with stage 5 CKD improved to better stages, some other patients' conditions declined to stage 5 from better stages at the end of postoperative month 3. No patient needed dialysis. The presence of urinary tract infections tended to affect GFR negatively. CONCLUSION: Estimated GFR, as a better indicator of renal function, is significantly affected by the PCNL procedure. While significant improvement was observed in late-stage patients with CKD, unexpected deterioration could occur in patients at earlier stages.  相似文献   
998.
PURPOSE: Stricture formation and obstruction are rare but significant complications after ureteroscopy (URS), and there are controversial studies regarding follow-up. Our study sought to determine the appropriate follow-up for patients without complications. PATIENTS AND METHODS: A total of 323 patients were treated with URS for removal of ureteric stones, and their charts were retrospectively reviewed. A semirigid ureteroscope was used in all patients, and stone disintegration was accomplished with a pneumatic lithotriptor. Postoperative evaluation included plain abdominal radiograph of the kidneys, ureters, and bladder (KUB) on day 1, intravenous urography (IVU) and/or ultrasonography at postoperative month 3 and annually thereafter in all patients. A KUB radiograph was also obtained on postoperative day (POD) 10 in patients with residual fragments. RESULTS: Complete records of 268 patients were available. The overall success rate was 95.5%. The KUB radiograph on POD 1 revealed complete stone removal in 217 (80.9%) patients, while residual fragments were seen in 40 (14.9%) patients, who were reevaluated on POD 10. Evaluation on POD 10 showed residual fragments in 15 patients, and URS was again performed in eight patients. Perioperative minor complications were observed in 18 (6.7%) patients. IVU performed in the third postoperative month showed stricture formation in two (0.7%) patients and silent obstruction in one (0.3%). No stricture formation was observed in asymptomatic patients after uncomplicated complete stone removal. After a mean follow-up of 27.4 +/- 13.7 (range 12-58) months, annual radiologic studies did not show any additional complications. CONCLUSIONS: Our results indicate that radiologic surveillance for stricture formation and obstruction is not mandatory after complete stone removal with uncomplicated URS.  相似文献   
999.
PURPOSE: Retroperitoneal lymph node dissection (RPLND) for testicular cancer is an important treatment modality for patients with stage I or IIA disease. Several urologists have previously reported the feasibility and usefulness of laparoscopic RPLND for such patients. The aim of this experimental pilot-feasibility study was to investigate whether visualization of retroperitoneal lymph nodes with patent blue violet (PBV) dye application is a feasible and an effective method during laparoscopic RPLND in a pig model. MATERIALS AND METHODS: Four 12-month-old white male pigs were included in the study. After PBV dye injection into the spermatic funicular and intratesticular parenchyma, the color changes in the retroperitoneal region were examined during transperitoneal laparoscopic visualization of the retroperitoneum. The time interval between the injection and the staining of lymphatic structures was measured for each intervention. Blue-stained retroperitoneal nodal tissues were dissected and removed by the laparoscopic approach and histologic examination was performed. RESULTS: After PBV dye injection, intense staining of the ipsilateral retroperitoneal lymphatic vessels and nodes was seen. Distribution of the PBV and the color changes of the retroperitoneal lymphatic structures were examined under laparoscopic vision in all pigs. All blue-stained retroperitoneal nodular tissues were removed laparoscopically and examined histologically. Histopathologic examination noted all specimens as lymph nodes with no toxic effects of PBV dye. CONCLUSION: We demonstrated that spermatic funicular injection of PVB dye is an effective and accurate method for retroperitoneal lymph node visualization in pigs. The use of this technique in combination with a laparoscopic approach makes RPLND easier and more effective.  相似文献   
1000.
Following acute organophosphate poisoning, intermediate syndrome essentially relates to the impairment of neuromuscular transmission due to prolonged inhibition of acetylcholinesterase activity at the muscle end-plate. However, the role of muscle injury in the development of intermedicate syndrome is not clear. The aim of this study was to determine whether the initial serum levels of the muscle enzymes can predict the subsequent development of intermediate syndrome. We reviewed the files of 47 adult patients with organophosphate poisoning between April 2003 and February 2006. The muscle enzymes were obtained within first 24 hr from each patient. Among the patients, 17% (n = 8) had severe poisoning and 83% (n = 39) mild poisoning. In 10 patients (21%), intermediate syndrome was observed. Of the patients with severe poisoning, 63% (n = 5) developed subsequent intermediate syndrome; among those with mild poisoning, 13% (n = 5) developed intermediate syndrome. There was no significant difference in initial serum levels of creatine kinase and aspartate aminotransferase between the patients with severe poisoning and mild poisoning, and there was no difference in initial serum levels of creatine kinase and aspartate aminotransferase between the patients with and without intermediate syndrome. The serum levels of the muscle enzymes measured within the first 24 hr may not predict the subsequent development of intermediate syndrome.  相似文献   
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