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Summary It is generally agreed that combined deficiency of selenium and vitamin E leads to several abnormalities including Kashin-Beck disease which is an endemic and chronic degenerative osteoarthrosis. The abnormalities can be reversed by the administration of various forms of selenium and vitamin E.The present study was designed to investigate the effects of dietary selenium and vitamin E on bone tissue and on the biomechanical properties of bone. Young rabbits of both sexes were fed with either a selenium- and vitamin E-adequate diet (control group), or a selenium- and vitamin E-deficient diet or a selenium-excess diet. The selenium-deficient diet resulted in a significant decrease in plasma selenium level and the selenium-excess diet resulted in a significant increase in the plasma selenium level with respect to the corresponding control values (p<0.05). The diets did not affect the blood cell counts considerably but erythrocyte glutathione peroxidase activity increased (decreased) relatively when the plasma selenium level increased (decreased) (p<0.05). The light microscopic investigations of the bone tissues of the two experimental groups indicate that the findings of the present work are compatible with osteomalacia. The biomechanical properties of the bones from the three groups were determined experimentally with bending tests. Both the Se-and vitamin E-deficient diet and the Se-excess diet decreased the biomechanical strength of the bones significantly while the bones belonging to the control group always had the largest modulus of elasticity (p<0.05).  相似文献   
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Although selenium, an essential trace element and a component of glutathione peroxidase, is known to protect the heart from ischemia-reperfusion (I/R)-induced injury, the mechanisms of this protection are not fully understood. For this purpose, isolated rat hearts were subjected to 30 min of global ischemia followed by 30 min of reperfusion; sodium selenite (25-1,000 nM) was added in the perfusion medium 10 min prior to ischemia, as well as during reperfusion. Selenium caused a dose-dependent improvement in cardiac performance and attenuated the decrease in the ratio of reduced glutathione to oxidized glutathione, as well as the increased level of malondialdehyde in I/R heart. Elevated ratios of nuclear factor-kappaB (NF-kappaB) in particulate and cytosolic fraction and of phosphorylated NF-kappaB and total NF-kappaB in I/R hearts were reduced by selenium. Cardiac dysfunction in hearts perfused with xanthine plus xanthine oxidase mixture, as well as hydrogen peroxide, or subjected to Ca2+ paradox was also attenuated by selenium. These data suggest that selenium protects the heart against I/R injury due to its action on the redox state and deactivation of NF-kappaB in I/R hearts.  相似文献   
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A polymorphic variant of the human angiotensin converting enzyme (ACE) gene was identified. The 'D' (rather than 'I') variant was associated with improvements in strength related to physical training. We set out to determine whether the response to different patterns of strength training might also differ. Ninty-nine Caucasian male non-elite athletes were randomly allocated into one of three groups: 31 non-training/control (CG: 31), single-set (SSG: 35) and multiple-set (MSG: 33). SSG and MSG trained three times a week for 6 weeks. Both training groups were underwent a strength-training program with two mesocycles (12-15 repetition maximum (RM) and 8-12 RM mesocycles). One RM loads in half squat and bench press were assessed before training and after the first and second mesocycles. ACE polymorphisms analysed by polymerase chain reaction (PCR) methods. Subjects with ACE II genotype in the MST group had improved strength development in 12-15 RM, while SST and MST groups had similar gains in 8-12 RM. Subjects with ACE DD genotype in both the SSG and the MSG had similar benefits from both 12-15 RM and 8-12 RM. Strength gains for subjects with ACE ID genotype in the SSG were similar to MSG gains in response to 8-12 RM loads but not with 12-15 RM loads. Additionally, subjects with DD genotype had superior strength gains in both strength training groups. Tailoring strength training programmes (single-set vs. multiple set) according to the athlete's ACE genotype may be advantageous.  相似文献   
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A total of 5,366 pregnant Turkish women were screened for hepatitis B surface antigen (HBsAg) and 225 (4.2%) of them were found to be positive. Hepatitis B e antigen (HBeAg) was detected in 6.2% of HBsAg-positive pregnant women. The overall prevalence of HBsAg and antibody to HBsAg (anti-HBs) among the spouses, previous children, mothers and first degree relatives of the HBsAg-positive pregnant women was 56%, 49%, 79% and 74% respectively. The prevalence of HBsAg is thus high in pregnant Turkish women with familial clustering of hepatitis B virus infection.  相似文献   
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The objective of this study was to investigate the incidence and density of Demodex folliculorum in the patients with rheumatoid arthritis (RA). Forty-one patients with RA and twenty-seven age and sex matched healthy controls were enrolled in this study. Disease Activity Score (DAS 28) was used for the assessment of disease activity. Out of 41 patients, 33 were females and 8 males. The mean disease duration was 10.9 ± 8.2 years. The mean DAS 28 was 3.8 ± 1.2. No statistically significant differences in the incidence and density of Demodex mites were found between patients with RA and controls. Although immunosuppression is thought to be a risk factor for the D. folliculorum infestation no such correlations could be found in the 41 immunosuppressed patients with RA, therefore, further studies with larger groups are needed.  相似文献   
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In patients with uncomplicated idiopathic hypercalciuria renal function is normal except for increased renal calcium excretion. In this study, the level of fractional urinary enzyme excretion was assessed in relation to calciuria. Fourteen patients with a mean age of 5.8 +/- 0.8 years who had daily urinary calcium excretion more than 4 mg/kg and with otherwise normal renal function tests were included in the study. None of the patients manifested either renal calculus or nephrocalcinosis. Fourteen normal children with a mean age of 5.4 +/- 0.74 were included in the control group. The level of the urinary N-acetyl beta-D glucosaminidase (NAG) to creatinine ratio, fractional aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH) excretion were not significantly different compared to the control group (p > 0.05). The patients were subdivided according to the type of hypercalciuria. The levels of NAG/creatinine ratio, fractional ALT, AST, ALP, LDH excretion were not significantly different in the absorptive type of calciuria group compared to the control group (p > 0.05). In conclusion, hypercalciuria during childhood which is 6.46 +/- 1.83 mg/kg/day is not related to the levels of NAG/creatinine ratio, fractional ALT, AST, ALP and LDH excretion in urine.  相似文献   
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BackgroundCardiovascular complication is one of the leading causes of mortality after liver transplantation (LT). Thus, a thorough cardiac evaluation is a must before proceeding to a liver transplant surgery. Percutaneous coronary intervention (PCI) with stent and to a lesser extent coronary artery bypass grafting (CABG) are both valuable treatment options for patients with coronary artery disease.MethodsA retrospective, single-center study that included patients who underwent cardiac intervention and subsequent LT for end-stage liver disease. All patients who had PCI or CABG were included in the study.ResultsTwenty-nine adult patients out of 51 had a cardiac intervention before liver transplantation. Twenty-four patients had a diagnostic PCI, 3 patients had therapeutic PCI with stent, and 2 had failed PCI and proceeded to CABG before liver transplant. The mean age of the patients was 60.5 years. There were 24 men. All patients had cirrhosis. The 2 CABG cases were done during the same admission with a 13- and 18-day interval between the CABG and the transplantation. Both cases were live-related liver transplantation. No mortality was reported.ConclusionIn case of PCI failure, CABG may be a valuable and safe treatment option for cirrhotic patients as a preparation for liver transplantation. Live donor liver transplantation may be a good back-up for those patients in case they develop hepatic decompensation.  相似文献   
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