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51.
Background: Elevated intra‐abdominal pressure and colostomy have adverse effects on colonic anastomoses. The aim of the present study was to investigate the effects of laparoscopic colon surgery with and without diverting colostomy on healing of colonic anastomoses in an experimental model. Methods: Thirty‐six male rats were divided into three equal groups: group 1, control (colonic anastomosis and anaesthesia for 180 min only); group 2, 180 min pneumoperitoneum and colonic anastomosis; and group 3, similar to group 2 with a proximal colostomy. On day 7, bursting pressures, tissue hydroxyproline and nitric oxide concentrations and histopathological inflammation scores were determined and compared. Results: Mean bursting pressures were higher in the control group than the two pneumoperitoneum groups (P = 0.0003). Mean tissue hydroxyproline concentrations showed no difference (P > 0.05). Mean tissue nitric oxide concentrations were significantly increased in the control group (P = 0.0013). Histopathological scores demonstrated increased inflammatory response in group 3 compared to the controls (P = 0.0009). Conclusion: Pneumoperitoneum delays collagen maturation and impairs anastomotic strength in the colon. Following pneumoperitoneum, performance of a diverting loop colostomy to protect the anastomosis will not have additional detrimental effects on anastomotic healing.  相似文献   
52.
In this study, we aimed to evaluate the genotoxic effects of fungicides fenarimol and propamocarb which are used to protect crops from fungi. For this reason, bone-marrow micronucleus and chromosome aberration tests were carried out in Swiss albino mice. Mice were injected with four different doses of fenarimol and propamocarb intraperitoneally; 50, 100, 200 and 400 mg/kg b.w. Fenarimol did not induce any significant increase in micronucleated erythrocytes after 24, 36, and 48 h treatment but it decreased the ratio of polychromatic/normochromatic erythrocytes at all dose groups and sampling intervals. Fenarimol did not increase the number of chromosome aberrations significantly, but it reduced the mitotic index at the higher doses (P < 0.05). Propamocarb did not increase the frequency of micronucleated erythrocytes, but decreased the polychromatic/normochromatic erythrocytes ratio at all sampling intervals. Propamocarb increased only gaps in total chromosome aberrations, but when gaps were excluded, there were no significant differences in total aberrations between the control and dose groups (P > 0.05). Propamocarb also reduced the mitotic index compared with the negative control group (P < 0.001). Contributing these results, we can suggest that fenarimol and propamocarb are non-genotoxic in mouse bone marrow in vivo but have cytotoxic effects.  相似文献   
53.
Abscess of the spleen   总被引:1,自引:0,他引:1  
Abscess of the spleen is a very rare lesion. In this study, 4 cases of splenic abscess are presented and discussed along with the literature. The cases were between 16 and 55 years-old and two of them had hematologic malignancy. All of them had been operated on because of acute abdomen, and in two cases splenic rupture was present. Only in one of the cases was salmonellosis detected by microbiological methods. By histological examination, expansion and congestion in splenic sinusoids, and foci of abscess including wide areas of necrosis and inflammatory infiltration by neutrophils were seen in all cases. The most frequent cause of splenic abscess is septic embolism arising from bacterial endocarditis. There are also a few splenic abscess cases seen with malignancies. While splenic abscess is seen rarely, it has a high rate of mortality when it is diagnosed late.  相似文献   
54.
A 9-year-old girl with neurofibromatosis type 1 (NF1) presented with a massive atypical meningioma and calvarial defect. Skull radiographs and cranial CT showed an extensive lytic bone lesion at the vertex. MRI demonstrated a large mass invading the calvarium and sagittal sinus. The histopathological and immunohistochemical diagnosis of the resected mass was atypical meningioma. To our knowledge, this is the first case of NF1 associated with atypical meningioma and massive calvarial defect in a child.  相似文献   
55.
56.
There have been conflicting reports concerning the effect of carnitine supplementation on lipid metabolism in patients on peritoneal dialysis (PD). We investigated several parameters of lipid metabolism in pediatric PD patients supplemented with carnitine. The study included 20 patients receiving PD (treatment group) aged 2–18 years and a matched healthy control group. In the treatment group, baseline triglyceride, total cholesterol, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, and apolipoprotein B levels were higher than in the control group. High-density lipoprotein cholesterol, free fatty acid, phospholipids, and apolipoprotein A-I levels were not different from those in the control group. The baseline plasma free carnitine level was lower and acyl-carnitine level was higher in the treatment group. No difference was found between the groups with respect to plasma total carnitine levels. Oral l-carnitine supplementation (50 mg/kg per day for 30 days) led to a significant decrease (from a baseline value of 146.6±51.8 mg/dl to 63.6±22.2 mg/dl, P<0.001) in apolipoprotein B levels, and no significant change in the other lipid parameters of the treatment group. Oral l-carnitine supplementation does not ameliorate the lipid profile in pediatric PD patients, but it causes a significant decrease in apolipoprotein B levels. Hence, carnitine supplementation may be recommended for decreasing apolipoprotein B levels in this patient population.  相似文献   
57.
Protective effect of quercetin on renal ischemia/reperfusion injury in rats   总被引:5,自引:0,他引:5  
BACKGROUND: There is increasing evidence to suggest that toxic oxygen radicals play a role in the pathogenesis of ischemia/reperfusion (I/R) injury in the kidney. The aim of this study was to evaluate whether quercetin, an oxygen free radical scavenger, protects kidney tissue. METHODS: A renal I/R injury was induced by a left renal pedicle occlusion by ischemia for 45 min, followed by 60 mins of reperfusion with contralateral nephrectomy in rats. The rats were pretreated intraperitoneally with a quercetin suspension (50 mg/kg) 60 min before the ischemia induction. Thiobarbituric acid reactive substances (TBARS), protein carbonyl content, tumor necrosis factor alpha (TNF-alpha), reduced glutathione (GSH) levels, myeloperoxidase (MPO) catalase (CAT) and superoxide dismutase (SOD) activities were determined in renal tissue. RESULTS: There were 3 groups of rats, the control group, the I/R group and the I/R+Q group. Our results indicate that TBARS, TNF-alpha levels, MPO activity and protein carbonyl content were significantly higher in the I/R group than those in the control group (p<0.05, p<0.01, p<0.01 and p<0.01, respectively). Quercetin administration significantly decreased these parameters (p<0.05, p<0.01, p<0.05 and p<0.01, respectively). GSH levels, SOD, and CAT activities significantly decreased after I/R injury when compared to the control group (p<0.01, p<0.05 and p<0.01, respectively). Quercetin treatment significantly increased GSH levels and activities of these enzymes when compared to the I/R group (p<0.05, p<0.01, p<0.05, respectively). CONCLUSIONS: These results suggest that quercetin reduces renal oxidative injury and facilitates repair. Quercetin can have a role in a renoprotective therapeutic regimen.  相似文献   
58.
Severe sepsis is a major public health concern and a burden on the healthcare system. Despite improvements in efforts to control the source of infection and increased recognition by healthcare providers of patients with the disease, the mortality rate remains unacceptably high, from 30% to 50%. The systemic inflammatory response syndrome criteria are used as diagnostic indicators of sepsis when they occur in patients with known or suspected infection. The outcome of a patient with severe sepsis is often related to the occurrence of sepsis-induced multiple organ dysfunction syndrome. Multiple organ dysfunction syndrome appears to result from a cascade of organism-related factors, inflammatory mediators, endothelial injury, disturbed hemostasis, and microcirculatory abnormalities. In patients with severe sepsis, derangements of inflammation and coagulation are tightly linked. Although numerous clinical trials focused on interventions in one or the other of the inflammatory and coagulation systems failed to show reduced mortality due to sepsis, a member of a new class of drugs called "cogins" was effective. In its active form, protein C has anti-inflammatory, antithrombotic, and profibrinolytic properties that can reduce organ injury associated with severe sepsis. A recombinant form of activated protein C, drotrecogin alfa (activated), significantly reduces 28-day mortality due to all causes in patients with severe sepsis and has an acceptable safety profile. This review provides an overview of severe sepsis, highlighting recent advances in treatment of the disease and the role of critical care nurses.  相似文献   
59.
OBJECTIVE: Aortic valve cusp extension and free-hand aortic valve replacement with autologous pericardium has been described. The long-term results were shown to be comparable with commercially available aortic bioprostheses. Nevertheless the relatively demanding surgical technique could not find wide acceptance. We developed a new design of a molded aortic valve, fashioned from autologous pericardium, treated briefly with glutaraldehyde, and simplified the implantation technique using single point attached commissures (SPAC). METHODS: Molded autologous valve prostheses were implanted in the subcoronary aortic position in 10 sheep with the commissures connected to the aortic wall at three single commissural points (SPAC). The prosthesis mean size was 21.6+/-1.3 mm and the construction time (excluding 10 min glutaraldehyde treatment) was 6.2+/-1.2 min. Cardiopulmonary bypass and cross-clamp time was 111.1+/-12.4 min and 75.0+/-16.3 min, respectively. Six sheep were euthanized after 201.2+/-10.3 days (6 months) and four sheep were euthanized after 330.8+/-6.5 days (11 months) postoperatively. RESULTS: In all sheep, the valve was immediately competent. At sacrifice, SPAC has proven to be well anchored to the aortic wall and the pericardial valve to be pliable in all cases. The maximum transvalvular gradient after cardiopulmonary bypass and at sacrifice was 3.7+/-2.2 mmHg and 10.6+/-5.2 mmHg, respectively. CONCLUSIONS: This new truly stentless molded autologous aortic valve with simplified implantation technique (SPAC) makes a reliable implantation in a standard timeframe possible. The simplicity of construction, low cost and absent need for anticoagulation of this molded autologous aortic bioprosthesis offers an attractive alternative and not only for patients in the developing world.  相似文献   
60.
The occurrence of true extrarenal Wilms' tumor is extremely rare. The most frequently noted extrarenal sites are the retroperitoneal and inguinal regions. In the female genital tract, the occurrence of Wilms' tumor has been documented in the uterus, endocervix, and ovary in isolated case reports. In this article the authors describe a case of ovarian Wilms' tumor in a 3.5-year-old girl. Her abdominal ultrasound scan and computed tomography scan showed a solid mass with cystic components on the left lower quadrant. Total excision was performed with left salpingo-oophorectomy. There was no other mass and also no evidence of metastasis. To the best of the authors' knowledge, this patient is the first reported case of primary ovarian Wilms' tumor arising in childhood.  相似文献   
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