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61.
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In Central Europe, the adults of nasal bird schistosomes of the genus Trichobilharzia have only been reported from experimental infections. Our work confirmed a relatively high prevalence of these parasites in wild anatid birds in the Czech Republic. The isolated miracidia were used to infect the Radix peregra (an autochtonous snail species) which proved to be a susceptible intermediate host. Subsequently, the emerged cercariae penetrated the skin of domestic ducks and adults were found in the nasal mucosa. It can be concluded that nasal bird schistosomes occur in the Czech fauna and are able to complete their life cycle under the conditions found in Central Europe.  相似文献   
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BACKGROUND: Preoperative delineation of any vascular anomalies offers planning for possible alteration of surgical procedures, especially in pediatric recipients undergoing living-related liver transplantation. PURPOSE: We assess the efficacy of three-dimensional (3D) multislice computed tomography (CT) angiography in the hope of replacing conventional angiography as the pretransplant evaluation of the hepatic vascular system for potential recipients of liver transplantation. METHODS: 3D CT angiography was performed in 38 children with biliary atresia. Conventional angiography was also performed in the first 15 patients. Twelve patients underwent living-related liver transplantation. The findings on 3D CT angiography were compared with conventional angiography and operative findings. RESULTS: 3D CT angiography was successfully performed in 37 pediatric patients. All findings of 3D CT angiography on hepatic artery, portal vein, and inferior vena cava paralleled those of catheter angiography and operative findings. Four patients were unsuitable to receive living grafts because of pathologic insults of the hepatic artery (one patient) and the portal vein (three patients). Three patients were advised to undergo a venous graft for portal anastomoses. Eight patients demonstrated portosystemic shunts that may require closure. CONCLUSION: 3D CT angiography proves to be a better tool in the demonstration of the vascular system and identification of pathologic insults in pediatric patients. It is superior to conventional angiography because it is less invasive, more convenient, and more efficient in providing thorough preoperative information that would have a major impact on patient selection and surgical planning.  相似文献   
65.
Oxidative stress plays an important role in cell death associated with many diseases. In the present study, concentration-dependence of hydrogen peroxide on rat pheochromocytoma (PC12) cell viability was studied. Preventive effects of antioxidants on the viability of these cells treated with 2 mM hydrogen peroxide were compared. Trolox and Stobadine, as chain-breaking antioxidants were studied in comparison with standardized extracts of flavonoids of Ginkgo biloba and Pycnogenol, known as agents effective in several diseases. All antioxidants increased the viability of hydrogen peroxide-treated PC12 cells. Flavonoid extracts were more effective than Trolox and Stobadine. Antioxidants were most effective if present after the oxidative treatment. As expected, the preloading with antioxidants was without effect on cell viability. Correlations between viability increase induced by antioxidants, and content of oxidation products of proteins and lipids were studied at concentrations of antioxidants mostly effective in preventing cell death: Trolox (10 microM), Stobadine (30 microM), Ginkgo biloba (160 microg/ml), Pycnogenol (100 microg/ml). In these concentrations, antioxidants did not statistically significantly decrease the content of protein carbonyls, with exception of Stobadine, which had no effect. Ginkgo biloba, Trolox and Stobadine intensively decreased the content of malondialdehyde, a product of lipid peroxidation. Pycnogenol was without any preventive effect. Concentrations of antioxidants with a large effect on viability of PC12 cells were not effective in preventing oxygen radical-induced injury of proteins. Antioxidants prevented the oxidative injury of lipids more effectively than that of proteins.  相似文献   
66.
The presence of elevated titres of anticardiolipin antibodies (ACA) and antihistone antibodies (AHA) in the blood serum is considered as one of serious reasons of repeated pregnancy losses. According to some reports, heparin significantly improves live birth rates in these cases. The aim of the work is an evaluation of the results of the heparin therapy in pregnant women with elevated titres of ACA and/or AHA in blood and bad obstetric anamnesis, or after sterility treatment. Our material consisted of three groups: the first one was composed of 25 ACA- and/or AHA-seropositive pregnant women 30.0 +/- 4.1 years old with 1-5 early miscarriages in past, the second one of six seropositive patients 31.3 +/- 2.8 years old, actually pregnant after the treatment of unexplained sterility (two of them after assisted reproduction) and, finally, in the third group were placed five pregnant ACA- and AHA-seronegative pregnant women 30.8 +/- 2.2 years old with 2-4 abortions of unexplained etiology in past. The ACA IgA, IgM and IgG and AHA IgG levels in blood sera were determined by ELISA. As a positive titre ACA in the class IgA was considered > 7 APL/ml, in the class IgM > 4 MPL/ml, IgG > 7 GPL/ml and in case of AHA IgG > 25 GPL/ml. The patients were treated by heparin 7500-30,000 units daily during all the pregnancy under the control of kaolin-kephalin time. In the first group, where 53 pregnancies from 56 were miscarried (94.6%), after the heparin therapy in 10 women 9 pregnancies of 11 (81.8%) were terminated by live birth (p < 0.001). One of the patients died three days after cesarean section because of myocardial infarction, probably due to sudden stopping of heparin. In the second group three women after heparin treatment delivered live babies, but three untreated aborted. In the last group only two women treated by heparin delivered live babies and three, despite treatment, miscarried. It should be concluded, that heparin therapy in ACA- and/or AHA-positive pregnant women might be a recommended therapeutic method. In cases of antiphospholipid syndrome a special precaution should be undertaken, when stopping the heparin. It seems, that double assay of ACA and AHA in patients with conception troubles might be usefull.  相似文献   
67.
The aim of this study was to determine influence of selected lifestyle factors on kidney cancer. The study brings data from two centres of international multicentric hospital-based analytical observational case-control studies. Data were obtained from a group of 300 patients newly diagnosed with kidney cancer (ICD-O-2 code C64) and 335 controls from two centres in the Czech Republic. Results showed that smoking increased OR to 1.09 (95% CI 0.77–1.55) and 1.06 (95% CI 0.73–1.52), but the results were not statistically significant. Obesity (BMI⩾30) created adjusted OR 1.71 (95% CI 1.11–2.66) and 1.44 (95% CI 0.91–2.28), showing a minor, statistically insignificant, effect of obesity on the development of kidney cancer. For hypertension, adjusted OR was 1.73 (95% CI 1.25–2.40), suggesting a minor to moderate effect of hypertension on kidney cancer. The analysis results showed a positive association between hereditary predisposition and the development of kidney cancer with an OR of 1.97 (95% CI 1.41–2.76) and 1.97 (95% CI 1.40–2.77) depending on the model of adjustment. The reasons for the high incidence of kidney cancer are not fully understood. Genetic polymorphisms, together with other lifestyle and environmental factors, are likely to contribute to various rates of kidney cancer incidence throughout the world.  相似文献   
68.
BACKGROUND: The aim of this study was to evaluate the clinical value of markers of bone remodeling in assessment of rate of bone loss in patients with multiple sclerosis (MS) long term treated with low dose glucocorticoids. METHODS: The study involved 70 patients with MS. Motor function of the patients was evaluated using the Kurtzke Expanded Disability Status Scale (KEDSS). Bone mineral density (BMD) was determined at the lumbar spine and proximal femur at baseline and after 1.8 +/- 0.8 years. Bone remodeling was assessed using circulating concentrations of type 1 collagen cross-linked C-telopeptide (beta CTX), aminoterminal propeptide of type I procollagen, and N-MID osteocalcin (OC). A control group of 140 age-matched healthy subjects was used to compare bone-turnover markers. RESULTS: The plasma CTX concentration was the most significant parameter of bone remodeling which correlated with the rate of bone loss and with the KEDSS. The rate of bone loss at the proximal femur was not significantly different between tertiles of plasma OC concentrations. CONCLUSION: In physically active patients with MS treated with low-dose GC, the bone-turnover markers were not different from controls. Patients having plasma CTX but markers of bone formation higher as compared to controls were confirmed 2 years later as bone losers.  相似文献   
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BACKGROUND: Fine-needle aspiration of the thyroid gland is a common procedure that is increasingly being used to evaluate thyroid nodules incidentally found by other imaging means such as computed tomography scans. Rare complications include hematoma, transient vocal cord paralysis, seeding of carcinoma cells, and infection. Of these, hematoma is the most common and is usually small and adequately treated with compression of the site. Only two cases have been previously reported describing large thyroid hematoma after fine-needle aspiration resulting in acute airway compromise and requiring surgical decompression. SUMMARY: We report an interesting case of large bilateral thyroid hematomas after routine fine-needle aspiration causing acute airway obstruction in a patient with hypertension and end stage renal disease taking aspirin.  相似文献   
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