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Purpose To investigate the effect of N-acetylcysteine on preventing pump-induced oxidoinflammatory response during cardiopulmonary bypass (CPB).Methods Forty patients undergoing coronary artery bypass grafting (CABG) were randomly divided into a study group (n = 20), given 50mgkg–1 N-acetylcysteine intravenously for 3 days, and a control group (n = 20) given saline. Serum samples were collected for measurement of myeloperoxidase (MPO), malondialdehyde (MDA), interleukin-6, 1-acid glycoprotein (AAGP), and C-reactive protein (CRP) during surgery and postoperatively.Results The MPO and MDA values showed a similar pattern during and after CPB in the study group, with significantly less variance than in the control group. Interleukin-6 showed similar patterns in the two groups, but the data from 30min after the start of CPB and from 6h post-CPB were significantly different. The AAGP and CRP values were both elevated during CPB in the two groups without a significant difference, but 6 and 24h post-CPB, the values were significantly higher in the control group than in the study group.Conclusions N-Acetylcysteine decreased pump-induced oxidoinflammatory response during CPB, suggesting that it could be a novel therapy for assisting in the prevention of CBP-induced oxidoinflammatory damage.  相似文献   
13.
PURPOSE: To evaluate erectile dysfunction, penile color Doppler ultrasound is currently considered the best method. But intracavernous injection is invasive and has adverse effects, such as prolonged erection and risk of priapism. In our study we want to evaluate whether vardenafil can be used instead of papaverine in penile Doppler ultrasonography. MATERIALS AND METHODS: A total of 24 patients with erectile dysfunction underwent color Doppler ultrasound before and after intracavernous injection of 60 mg papaverine with genital and audiovisual sexual stimulation. Peak flow and end diastolic velocity were measured in the recorded waveforms obtained 0, 1, 5, 10 and 20 min after injection. The patients also underwent color Doppler ultrasound after a 10-mg oral dose of vardenafil with genital and audiovisual sexual stimulation and at least 5 days after the prior examination. The same parameters were measured at 30, 45, 60, 75 and 90 min after the drug administration. We compared the results with the values obtained after papaverine injection. RESULTS: After oral vardenafil mean peak flow velocity significantly increased starting at 30 min and achieving a maximum value at 60 min. There were no significant differences in the 2 methods in mean peak velocity 1, 5, 10 and 20 min after papaverine injection, and 30, 45, 60, 75 and 90 min after oral vardenafil administration. Although papaverine injection is the gold standard for penile color Doppler ultrasound, it has severe adverse effects such as prolonged erection which we observed in 3 patients (12.5%) and required pharmacological detumescence. After vardenafil no severe adverse effects were observed. CONCLUSIONS: Vardenafil administration achieved increased peak flow velocity comparable to that after intracavernous papaverine injection. With no prolonged erection vardenafil is a safer alternative compared to more invasive intracavernous injection and is also an alternative for patients who fear injections.  相似文献   
14.
The purpose of this experimental study was to evaluate possible upgrading effects of systemic creatine monohydrate administration on the reinnervation of denervated muscle. At the same time, the protective effect of the agent on denervated muscle until ultimate reinnervation after nerve repair was quantified. The functional outcome of muscle reinnervation after creatine monohydrate application was compared with a control group. Forty adult Wistar rats weighing 180 to 220 g were used. The right sciatic nerve was dissected, exposed, and cut at the level of the midthigh in all rats. The experimental design consisted of two groups: experimental (animals were fed creatine monohydrate) and control (gavage feeding was provided by saline). Both groups were divided into two subgroups: subgroups A and B for the experimental group, and subgroups C and D for the control group. In subgroups A and C, the nerves were repaired with four 10-0 epineurial stitches. In subgroups B and D, both the proximal and distal ends of the nerves were ligated and no neural anastomosis was performed. In the experimental groups (subgroups A and B), the rats were fed by daily supplementation of oral creatine monohydrate, 300 mg/kg body weight. In the controls (subgroups C and D), oral supplementation was provided by saline. Functional recovery was evaluated using walking track analysis, pinching test, and limb circumference and toe contracture measurements at the end of 6 months, after which the rats were sacrificed and nerve specimens from both ends of the repair sites and the whole gastrocnemius muscle were obtained to document the results of the histomorphometric and histochemical studies, including light microscopic examinations and muscle weight measurements. The mean functional recovery values in subgroups A, B, C, and D were 91 percent, 80 percent, 87 percent, and 59 percent, respectively. Functional recovery improved significantly in the experimental groups (in both the surgically repaired and unrepaired subgroups), compared with the control groups (p<0.05). The pinching test revealed a statistically significant difference in nerve conduction between the experimental and control groups (p<0.05). The limb circumference ratio of the surgically treated side to the untouched side in subgroups A, B, C, and D were noted as 0.95, 0.89, 0.91, and 0.87, respectively, and the difference between the experimental and the control groups was statistically significant (p<0.05). The differences between subgroups A and B, C and D, A and C, and B and D were also significant. The surgically repaired and creatine-supplemented subgroups demonstrated the best results in toe contracture index. The muscle weight measurement results were concordant with the results of the limb circumference ratio. In both surgically repaired subgroups (subgroups A and C), there were qualitatively significant amounts of myelinated fibers in the nerve distal to the anastomotic site; there were no myelinated fibers in the distal stumps of subgroups B and D. Histochemical analyses of the contents of the muscle fiber types also revealed no significant difference. Overall, the results showed the useful effect of oral creatine supplementation on both surgically repaired and unrepaired nerve injuries. The best results were obtained from surgically repaired nerve injuries and also from the systemic creatine-supplemented subgroups. This study confirms that systemic administration of creatine monohydrate has a protective and upgrading effect on the functional properties of denervated muscle, especially in surgically reinnervated subjects.  相似文献   
15.
BACKGROUND AND PURPOSE: Endoscopic subureteral injection of tissue-augmenting substances has become an alternative to antibiotic prophylaxis and open surgery for the management of vesicoureteral reflux (VUR). Several injectable materials have been tried for this purpose. In this study, we tried to determine the efficacy of dextranomer/hyaluronic acid copolymer (Dx/HA) injection for the treatment of VUR in renal-transplant candidates. PATIENTS AND METHODS: A total of 21 transplant candidates (29 ureteral units; 13 females, 8 males) with a mean age of 20.2 years (range 14-26 years) underwent endoscopic correction of VUR with Dx/HA. Diagnosis of VUR was made by voiding cystourethrography. The efficacy of the treatment was assessed with voiding cystourethrography at 3 months and 1 year postoperatively. Renal transplantation with living related donor organs was performed in 11 of the 21 patients. RESULTS: Endoscopic treatment was performed without complication in all cases. Higher success rates were obtained in patients with low-grade reflux, the overall success rate in the series being 82.7%. The mean follow- up after renal transplantation was 21.8 months (range 5-45 months). In one patient, reflux recurred after renal transplantation and was treated successfully by a repeat Dx/HA injection. The urine cultures of all patients remained sterile. CONCLUSION: Transplant candidates with VUR can be treated with Dx/HA, which cured the majority of our patients after one or two treatments with few low side effects. Endoscopic subureteral injection of Dx/HA has become an alternative treatment for VUR in transplant candidates. Long-term results are needed before making a final statement about its value.  相似文献   
16.
Inflammatory Pseudotumor of the Spleen: Report of a Case   总被引:1,自引:0,他引:1  
Alimoglu O  Cevikbas U 《Surgery today》2003,33(12):960-964
We report the case of an inflammatory pseudotumor of the spleen in an asymptomatic 55-year-old woman, whose lesion was accidentally found and clinically misdiagnosed to be lymphoma. An inflammatory pseudotumor of the spleen was histopathologically diagnosed following a splenectomy. This lesion is a benign, reactive, and inflammatory process and its etiopathogenesis still remains elusive. The preoperative diagnosis is difficult and the optimal management of the asymptomastic patient with the disease is unclear. This entity should be kept in mind in the differential diagnosis of splenic space-occupying lesions.  相似文献   
17.
BACKGROUND: There are no standard criteria for the timing of drain removal. The objective of this study was to determine whether the macroscopic appearance of chest tube drainage fluid to serosanguineous may be used as a criteria for drain removal. METHODS: 2,359 patients were assessed retrospectively and 80 randomized patients were followed prospectively who underwent cardiac surgery. In both parts of the study, patients were divided into two groups according to the timing of drain removal. Group I consisted of patients whose chest tubes were removed as soon as the macroscopic appearance of the drainage fluid turned to serosanguineous. Group II consisted of patients whose chest tubes were removed at the second postoperative day when the drainage output declined to less than 50 mL in a five-hour period. In the retrospective part, cases of hemodynamically significant pericardial effusion observed within seven days postoperatively were reviewed. In the prospective part, just before the drain removal, the fluid sample hematocrit obtained from the drain lines and patients' blood hematocrit were measured and recorded. Patients were evaluated with echocardiography for pericardial effusion. RESULTS: No statistically significant difference was detected in the frequency of hemodynamically significant pericardial effusion and incidence or amount of pericardial effusion between the two study groups. The drain hematocrit to blood hematocrit ratios before drain removal showed a significant correlation with pericardial effusion.The strength of correlation between the drain hematocrit to blood hematocrit ratios before drain removal and pericardial effusion was also studied using receiver operating characteristic curve, which suggests that a drain hematocrit to blood hematocrit ratio of < or = 0.3 is strongly predictive that pericardial effusion would be absent or mild between the fifth and seventh postoperative days. CONCLUSIONS: It is safe to remove the chest tubes as soon as the macroscopic appearance of the drainage fluid turns to serosanguineous since this practically indicates cessation of active bleeding.  相似文献   
18.
Our goal was to determine the primary stability of overlapping osteochondral grafts used in mosaicplasty by studying the effect of overlapping in an ex vivo model. Osteochondral grafts, 10 mm in diameter, were transplanted from the trochlea of cow femurs to the weight-bearing area of the lateral femoral condyle with 0, 15, or 30% overlap. The grafts were pushed in with a probe at a rate of 2 mm/min, and load (N)-displacement (mm) curves were recorded. In Group I (control, 0% overlap), insertion 1 and 2 mm below the cartilage level could be reached at 572.3 +/- 273.6 and 999.3 +/- 427.6 N, respectively. In Group II (15% overlap), insertion 1 and 2 mm below the cartilage level could be reached at 263.6 +/- 91.7 and 746.6 +/- 88.0 N, respectively. In Group III (30% overlap), insertion 1 and 2 mm below the cartilage level could be reached at 179.4 +/- 31.2 and 657.0 +/- 106.5 N, respectively. The loads that were necessary to produce a 1-mm dent in the grafts were significantly different between Groups I and II and Groups I and III (p < 0.05). These results suggest that stability may be reduced by graft overlapping in mosaicplasty surgery. The results of this ex vivo animal study contribute to a more complete understanding of the primary stability of osteochondral grafts in an overlapping position as well as postoperative protocols.  相似文献   
19.
OBJECTIVE: The objective of this prospective study was to determine the feasibility of sentinel lymph node (SLN) detection in patients with cervical cancer using lymphoscintigraphy (LS), gamma probe, and blue dye. METHODS: A total of 32 patients with early stage cervical cancer (FIGO IA2-IIA) who were treated with total abdominal hysterectomy and bilateral pelvic and paraortic lymphadenectomy underwent SLN biopsy. LS was performed on all the patients following the injection of 74 MBq technetium-99m-nanocolloid pericervically. The first appearing persistent focal accumulation on either dynamic or static images of LS was considered to be an SLN. Blue dye was injected just prior to surgical incision in 16 patients (50%) at the same locations as the radioactive isotope injection. During the operation, blue-stained node(s) were excised as SLNs. For gamma probe, a lymph node was accepted as an SLN, if its ex vivo radioactive counts were at least 10-fold above background radioactivity. SLNs, which were negative by routine hematoxylin and eosin (H&E) examination, were histopathologically reevaluated for the presence of micrometastases by step sectioning and immunohistochemical staining with pancytokeratin. RESULTS: At least one SLN was identified for each patient by gamma probe. Intraoperative gamma probe was the most sensitive method with a technical success rate of SLN detection of 100% (32/32), followed by LS 87.5% (28/32) and blue dye 68.8% (11/16), respectively. The average number of SLNs per patient detected by gamma probe was 2.09 (range 1-5). The localizations of the SLNs were external iliac 47.8%, obturatory 32.8%, common iliac 9%, paraaortic 4.4%, and paracervical 6%. Micrometastases, not detected by routine H&E were found by immunohistochemistry in one patient. On the basis of the histopathological analysis, the negative predictive value for predicting metastases was 100%, and there were no false-negative results. CONCLUSIONS: Preoperative LS with radiocolloids, intraoperative lymphatic mapping with blue dye and gamma probe are all feasible methods comparable with each other for SLN detection in early stage cervical cancer patients, but gamma probe is the most useful method in terms of technical success.  相似文献   
20.
The authors report on a patient who underwent renal artery stent placement 6 hours after transplantation due to acute hypoperfusion of the transplant, which was diagnosed with intraoperative Doppler ultrasonography. Extensive atherosclerotic disease of the cadaveric transplant renal artery necessitated endarterectomy before creation of the anastomosis, and no further surgical options were considered feasible by the transplant surgeon. Six hours after the transplantation, percutaneous transluminal renal angioplasty and stent placement were performed, resulting in restoration of normal arterial flow and rescue of allograft function.  相似文献   
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