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11.
Objective To investigate whether stone dimension is a restrictive factor for ureterorenoscopic procedures. Materials and methods A group of 416 patients who had undergone ureterorenoscopic pneumatic lithotripsy (URS-PL) for lower ureteral stones between January 1999 and June 2006 in our clinic had been evaluated retrospectively. Two hundred and seventy (270, 64.9%) patients were men and 146 (35.1%) were women. The mean age of the patients was 36.61 (±12.43) years. Patients were grouped according to stone dimension; 193 patients with stones smaller than 1 cm being group 1 and 223 patients with stones ≥1 cm in dimension being group 2. Stone-free rate, operative time and rate of complications of the groups were compared. Pearson’s correlation test, χ2 test, Fischer’s exact test and Student’s t-test were used for the statistical analysis. The p value was accepted as being meaningful if p < 0.05. Results For group 1, the mean operative time was 39.19 (±18.33) min. Proximal stone migration in five and false passage formation in three patients was observed. Three patients were stone-free after a second session of URS-PL. The cumulative stone-free rate was 97.4% (188/193). For group 2, the mean operative time was 48.5 (±11.31) min. About 208 (93.27%) patients were stone-free after the first session and an additional eight patients became stone-free after the second session of URS-PL. False passage, ureteral perforation, ureteral avulsion and stricture were observed in four, six, one and one patients, respectively. No proximal stone migration was observed. The cumulative stone-free rate was 96.86% (216/223). Conclusions The effectiveness of ureterorenoscopy (URS) in the treatment of distal ureteral stones was independent of stone dimension. However, the operative time was longer and the rate of perforation was higher in stones with a diameter ≥1 cm. On the other hand, the migration rate was higher in stones <1 cm in diameter. Generally speaking, there was no meaningful effect of stone dimension on complication rates.  相似文献   
12.
Although truncus arteriosus is often treated with low mortality and morbidity rates, truncal valve patency and aortic arch and coronary artery anomalies are factors that can contribute to a worse outcome. In this report, we present our experience with the combination of Rastelli and Norwood procedures for the treatment of Type I truncus arteriosus that was complicated by a hypoplastic aortic arch.  相似文献   
13.
The surface of diarthrodial joints is covered by hyaline cartilage whose regeneration capacity is extremely limited. Conventional surgical techniques enable repair of full-thickness articular cartilage defects only by fibrous cartilage having poor mechanical properties. Recently, new techniques have been developed to provide hyaline or hyaline-like repair tissue in the treatment of full-thickness cartilage defects. Autologous osteochondral transplantation involves press-fit implantation of both bone and cartilage obtained from healthy articular surface. The principal indication for this technique is unifocal full-thickness chondral or osteochondral defects measuring 1 to 4 square centimeters. This surgical procedure can be performed openly or arthroscopically. The graft should be placed vertically and evenly to the joint surface. Although short-term and mid-term results are satisfactory, several problems have been reported including donor site morbidity, damage to cartilage, and incongruity and incorporation of the graft. Autologous osteochondral transplantation provides viable osteochondral units at a single stage and eliminates the need for culturing chondrocytes which is quite expensive. Currently, no surgical technique or medical treatment provide complete healing of articular cartilage defects. Autologous osteochondral transplantation is an important stage worthy of improvement in this respect.  相似文献   
14.
15.
Introduction. This study was designed to investigate whether 3-amino benzamide (3-AB), a poly (ADP-ribose) polymerase (PARP) inhibitor, has a protective effect on kidney injury induced by renal ischemia/reperfusion (I/R) by decreasing oxidative and nitrosative stress on renal dysfunction and injury. Materials and Methods. Thirty-two male Sprague-Dawley rats were divided into four groups: sham-operated, sham-operated + 3-AB, I/R, I/R + 3-AB. Rats were given 3-AB (100 mg/kg/day ip) 14 days prior to I/R. I/R and I/R + 3-AB groups underwent 60 min of bilateral renal ischemia followed by 6 h of reperfusion. After reperfusion, kidneys and blood were obtained for evaluation. Superoxide dismutase, glutathione peroxidase, malondialdehide, protein carbonyl content, and nitrite/nitrate level (NOx) were determined in the renal tissue. Serum creatinine (SCr), blood urea nitrogen (BUN), and aspartate aminotransferase (AST) were determined in the blood. Additionally, renal sections were used for histological grade of renal injury. Results. 3-AB significantly reduced the I/R-induced increases in SCr, BUN, and AST. In addition, 3-AB markedly reduced elevated oxidative stress product, restored decreased antioxidant enzymes, and attenuated histological alterations. Moreover, 3-AB attenuated the tissue NOx levels, indicating reduced NO production. Conclusions. 3-AB has beneficial effect on renal glomerular and tubular dysfunction in rats' kidneys subjected to I/R injury. Moreover, 3-AB has ameliorating effect on both oxidative stress and nitrosative stress of the kidneys, which correlated with histopathological evaluation.  相似文献   
16.
Growing participation of children in sports has resulted in an increased incidence of sports injuries. Although methodological differences in epidemiologic studies largely prevent precise comparisons, it appears that young athletes participating in combat and contact sports seem to be more prone to injuries. Knee and ankle injuries are the most commonly encountered problems and chronic events are more prevalent than acute ones. The occurrence of athletic injuries is multifactorial and may present differences with respect to sex and the sports branch involved. An analytical approach of all relevant groups (parents, coaches, physical education teachers, health personnel) is necessary to understand, treat, and prevent athletic injuries in children.  相似文献   
17.

Background

Comparative effectiveness research in spine surgery is still a rarity. In this study, pain alleviation and quality of life (QoL) improvement after lumbar total disc arthroplasty (TDA) and anterior lumbar interbody fusion (ALIF) were anonymously compared by surgeon and implant.

Methods

A total of 534 monosegmental TDAs from the SWISSspine registry were analyzed. Mean age was 42 years (19–65 years), 59 % were females. Fifty cases with ALIF were documented in the international Spine Tango registry and used as concurrent comparator group for the pain analysis. Mean age was 46 years (21–69 years), 78 % were females. The average follow-up time in both samples was 1 year. Comparison of back/leg pain alleviation and QoL improvement was performed. Unadjusted and adjusted probabilities for achievement of minimum clinically relevant improvements of 18 VAS points or 0.25 EQ-5D points were calculated for each surgeon.

Results

Mean preoperative back pain decreased from 69 to 30 points at 1 year (ØΔ 39pts) after TDA, and from 66 to 27 points after ALIF (ØΔ 39pts). Mean preoperative QoL improved from 0.34 to 0.74 points at 1 year (ØΔ 0.40pts). There were surgeons with better patient selection, indicated by lower adjusted probabilities reflecting worsening of outcomes if they had treated an average patient sample. ALIF had similar pain alleviation than TDA.

Conclusions

Pain alleviation after TDA and ALIF was similar. Differences in surgeon’s patient selection based on pain and QoL were revealed. Some surgeons seem to miss the full therapeutic potential of TDA by selecting patients with lower symptom severity.  相似文献   
18.
Transcaval extension of the thymoma to the right atrium has very rarely been reported, and cardiopulmonary bypass is recommended for successful resection. An invasive thymoma with intravascular invasion of the superior vena cava, and the left innominate vein extending into the right atrium was presented. Intra-atrial extension was resected through a transient external shunt from the inferior vena cava to the main pulmonary artery. We discussed the feasibility of this surgical technique and possible advantages of cardiopulmonary bypass avoidance.  相似文献   
19.

Aim

To compare the histopathological findings on fine needle aspiration (FNA) biopsy of thyroid nodules and thyroidectomy surgical specimens, in order to determine the efficacy, specificity and sensitivity of FNA in the diagnosis of thyroid malignancy.

Methods

The data on a series of 86 patients who underwent thyroidectomy for thyroid nodules were evaluated retrospectively. The demographic characteristics and imaging findings were reviewed, and the histopathological findings on the preoperative FNA biopsy and the surgical thyroid specimen were compared.

Results

The FNA findings on the thyroid nodules were: 32.1% benign, 12.2% malignant, 2.7% suspicion of malignancy, 6% atypia of undetermined significance, 15.7% follicular lesion and/or suspicion of follicular neoplasm, and in 31.3% the aspirate was inadequate. The postoperative histopathological specimens were evaluated as 31 malignant (36%) and 55 benign (64%). Statistically significant correlation was demonstrated between the FNA and the postoperative histopathological findings (p<0.05). In this series, the overall sensitivity of FNA biopsy was 10%, the specificity 70.9%, the positive predictive value 16% and the negative predictive value 58%.

Conclusions

This study identified a high negative predictive value of FNA biopsy, and an increased rate of “nondiagnostic” and “microcarcinoma” outcomes, but the sensitivity of FNA in the preoperative diagnosis of thyroid malignancy was low.
  相似文献   
20.
Nephrotoxicity is a major complication of acetaminophen (APAP), a widely used analgesic and antipyretic drug, and there is no specific treatment for APAP-induced renal damage. It has been reported that reactive oxygen metabolites or free radicals are important mediators of APAP toxicity. In this study, the protective role of melatonin (MLT) on APAP-induced nephrotoxicity was investigated in rats. For this purpose, nephrotoxicity was induced in male Wistar albino rats by intraperitoneal (i.p.) administration of a single dose of 1,000 mg/kg APAP. Some of these rats also received i.p. melatonin (10 mg/kg) 20 min after administration of APAP. The rats were sacrificed 24 h after administration of APAP. Urea and creatinine levels were measured in the blood, and levels of malondialdehyde (MDA) and glutathione (GSH), and glutathione peroxidase (GSH-Px), catalase (CAT), and superoxide dismutase (SOD) activity were determined in renal tissue. Serum urea and creatinine levels increased significantly as a result of APAP nephrotoxicity. A significant increase in MDA and decreases in GSH level and GSH-Px, CAT, and SOD activity indicated that APAP-induced renal damage was mediated through oxidative stress. Significant beneficial changes were noted in serum and tissue oxidative stress indicators in rats treated with MLT. These biochemical observations were supplemented by histopathological examination of kidney sections, which revealed that MLT also reduced the severity of APAP-induced histological alterations in the kidney. These results indicate that administration of APAP causes oxidative stress to renal tissue and that MLT protects against the oxidative damage associated with APAP.  相似文献   
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