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51.
Recent evidence suggests that certain Fc gamma receptor alleles are genetic risk factors for infectious diseases. In this study, we evaluated Fc gamma RIIa polymorphism in patients with brucellosis. In a case-control study, the frequency of two alleles and three genotypes for Fc gamma RIIa were measured by PCR in 150 patients with brucellosis and 125 healthy controls. The H131 and R131 alleles were found in 133 (44.3%) and 167 patients (47.6%), respectively. The frequencies for the three genotypes (a/a, a/r, r/r) were 10 (6.7%), 113 (75.3%) and 27 (18%), respectively. There was no significant difference in the distribution of Fc gamma RIIa genotypes and the two allelic forms between the patients and controls. Our study indicates that Fc gamma RIIa polymorphism is not decisive for the acquisition of brucellosis.  相似文献   
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BACKGROUND: Decision tree classification is a standard machine learning technique that has been used for a wide range of applications. Patients with inflammatory bowel disease (IBD) are at increased risk of developing low bone mineral density (BMD). This study aimed at developing a new approach to select truly affected IBD patients who are indicated for densitometry, hence, subjecting fewer patients for bone densitometry and reducing expenses. MATERIALS AND METHODS: Simple decision trees have been developed by means of WEKA (Waikato Environment for Knowledge Analysis) package of machine learning algorithms to predict factors influencing the bone density among IBD patients. The BMD status was the outcome variable whereas age, sex, duration of disease, smoking status, corticosteroid use, oral contraceptive use, calcium or vitamin D supplementation, menstruation, milk abstinence, BMI, and levels of calcium, phosphorous, alkaline phosphatase, and 25-OH vitamin D were all attributes. RESULTS: Testing showed the decision trees to have sensitivities of 65.7-82.8%, specificities of 95.2-96.3%, accuracies of 86.2-89.8%, and Matthews correlation coefficients of 0.68-0.79. Smoking status was the most significant node (root) for ulcerative colitis and IBD-associated trees whereas calcium status was the root of Crohn's disease patients' decision tree. CONCLUSION: BD specialists could use such decision trees to reduce substantially the number of patients referred for bone densitometry and potentially save resources.  相似文献   
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BACKGROUND: The association of changes in oxidative and proinflammatory states with vascular function after diet and exercise intervention among obese children has not been previously explored. METHODS: In this 6-week diet and exercise intervention study in 35 obese children, age 12 to 18 years, we evaluated the relationship between changes in anthropometric indices, measures of insulin resistance, C-reactive protein (CRP), oxidized LDL (ox-LDL), and oxidative stress markers with changes in carotid intima-media thickness (C-IMT) and flow mediated dilation (FMD) of the brachial artery. RESULTS: At the end of the study, body mass index (BMI), waist circumference, and percentage body fat were decreased (P <0.05), but participants remained overweight (BMI > or = 95th percentile). Although FMD improved (P <0.05), the improvement in C-IMT did not reach statistical significance. The changes in BMI, waist circumference, fat mass, ox-LDL, malondialdehyde (MDA), CRP, insulin, and homeostasis model assessment for insulin resistance (HOMA-IR) had an inverse correlation with the changes in mean FMD after adjustment for age and sex, with the highest correlations documented for ox-LDL, CRP, and WC. The age- and sex-adjusted changes in ox-LDL, waist circumference, CRP, MDA, and body fat mass had the highest correlations with changes in C-IMT. CONCLUSIONS: Our findings suggest that a common inflammatory stress condition associated with childhood obesity, notably with abdominal fat deposition, may play a role in the development of the earliest stages of proatherosclerotic inflammatory processes and subsequent vascular dysfunction. These changes might be partially reversible by short-term diet and exercise intervention, even if patients do not reach ideal body weight.  相似文献   
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Crimean-Congo hemorrhagic fever (CCHF) has repeatedly caused nosocomial outbreaks among hospital staff. In the summer of 2003, we studied the seroprevalence of anti-CCHF IgG among health care workers who had come in contact with Crimean-Congo hemorrhagic fever patients from three referral hospitals in endemic regions of Iran. A total of 223 eligible staff were examined. Whereas 5 of 129 (3.87%) exposed health care workers tested positive, none of the 94 in the unexposed group did (P=0.075). Seropositivity was more frequent among those whose intact skin had come in contact with nonsanguineous body fluids (9.52%) and those who had had percutaneous contacts (7.14%). Health care workers exposed to Crimean-Congo hemorrhagic fever patients, those who live in Systan-Baluchestan province, and older health care workers were more prone to seropositivity. Where introduction of high-risk modes of contact cannot be confined, we propose that health care workers take all the protective measures when handling Crimean-Congo hemorrhagic fever patients, particularly their blood and other body fluids.  相似文献   
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BACKGROUND: Although some studies have described rehospitalization after transplantation, few have focused on risk factors and consequences of prolonged hospital stay. Our goal was to determine the causes, risk factors, and outcomes of prolonged rehospitalizations after renal transplantation. PATIENTS AND METHODS: In this retrospective study, 574 randomly selected rehospitalization records of kidney transplant recipients were reviewed from 1994 to 2006. Admissions were divided into group 1, prolonged stay (length of stay >14 days, n=149), and group II, short stay (length of stay 62% of all hospital costs; however, they comprised only 26% of the patients. High-risk kidney transplant recipients for prolonged hospitalizations should be closely observed for infections and graft rejection.  相似文献   
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AIM: To investigate the relationship between near point of convergence (NPC) and mild cognitive impairment (MCI) in the general elderly population. METHODS: The present report is a part of the Tehran Geriatric Eye Study (TGES): a population-based cross-sectional study conducted on individuals 60 years of age and above living in Tehran, Iran using the multi-stage stratified random cluster sampling method. Cognitive status was assessed using the Persian version of the Mini-Mental State Examination (MMSE). All study participants underwent complete ocular examination including measurement of uncorrected and best-corrected visual acuity, objective and subjective refraction, cover testing, NPC measurement, and slit-lamp biomicroscopy. RESULTS: The data of 1190 individuals were analyzed for this report. The mean age of the participants analyzed was 66.82±5.42 (60-92y) and 728 (61.2%) of them were female. Patients with MCI had a significantly more receded NPC compared to subjects with normal cognitive status (10.89±3.58 vs 7.76±2.71 cm, P<0.001). In the multivariable logistic regression model and in the presence of confounding variables, a receded NPC was statistically significantly associated with an increased risk of MCI (odds ratio: 1.334, 95% confidence interval: 1.263 to 1.410, P<0.001). According to receiver operating characteristic (ROC) analysis, a cut point NPC> 8.5 cm (area under the curve: 0.764, P<0.001) could predict the presence of MCI with a sensitivity and specificity of 70.9% and 69.5%, respectively. CONCLUSION: A receded NPC can be clinically proposed as a predictor of MCI in older adults. It is recommended that elderly with a receded NPC>8.50 cm undergo detailed cognitive screening for a definite diagnosis of MCI. In this case, the necessary interventions can be carried out to slow down MCI progression to dementia.  相似文献   
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