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61.
Weathered crude oil (WCO) removals in shoreline sediment samples were monitored for 60 days in bioremediation experimentation. Experimental modeling was carried out using statistical design of experiments. At optimum conditions maximum of 83.13, 78.06 and 69.92% WCO removals were observed for 2, 16 and 30 g/kg initial oil concentrations, respectively. Significant variations in the crude oil degradation pattern were observed with respect to oil, nutrient and microorganism contents. Crude oil bioremediation were successfully described by a first-order kinetic model. The study indicated that the rate of hydrocarbon biodegradation increased with decrease of crude oil concentrations.  相似文献   
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Neonatal sepsis is a disease of infants who are less than 1 month of age. These infants are clinically ill, and their blood culture are positive for bacteria. The reported incidence of neonatal sepsis for all infants is 1 to 10 per 1000 live births. The mortality rate is 4.2-26%. The clinical signs are not specific and diagnosis of neonatal sepsis is one of the most difficult tasks in clinical medicine. The aim of this work was determination of CD11b sensitivity and specificity for early detection of neonatal sepsis. We studied 65 neonates with gestational age of 27 to 38 weeks who were suspected for sepsis within the 28 days of life. Whole blood was obtained from neonates to determine CD11b expression on peripheral blood neutrophils by flow cytometry. C-Reactive protein (CRP) was measured qualitatively. Neonates were divided into two groups. Classification was based on the result of the blood culture. In the sepsis group all of the neonates (n=8) showed positive blood culture and clinical symptoms. In the suspected group (n=57) the neonates showed clinical signs but blood cultures were negative. Sensitivity and specificity of CD11b were 75%, 100% respectively. Also positive and negative predictive values of CD11b were 100% and 86% respectively. Results of present study and previous studies showed that measurement of neutrophil surface markers can be useful for diagnosis of infection in the early phases. Also, the quantitative measurement of CRP in addition to CD11b further enhances the ability to diagnose infections and improves sensitivity and negative predictive value by 100%.  相似文献   
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Background/Aims: Acute cholestasis is associated with cardiovascular complications. The purpose of the present study was to investigate the effect of cholestasis on heart apoptosis and the involvement of nitric oxide (NO) and oxidative stress in the possible altered apoptosis of cholestatic hearts. Methods: Cholestasis was induced by bile duct–ligation, and sham‐operated mice served as controls. Three days after the surgery, heart tissues were evaluated for apoptosis and the level of malondialdehyde (MDA), and the activities of catalase (CAT), glutathione peroxidase (GSHPx) and superoxide dismutase (SOD) have been studied in cardiac tissues. The role of treatment with l ‐NAME, a non‐selective inhibitor of NO synthase, or with d ‐NAME, an inactive isomer of l ‐NAME, on cholestatic and sham cardiac apoptosis, level of MDA and CAT, SOD and GSHPx activities was also investigated. The content of NO in cardiac tissue was also determined. Results: Cholestatic hearts showed structural abnormalities and increased apoptosis compared with sham hearts. Treatment with l ‐NAME, but not d ‐NAME, improved both structural abnormalities and enhanced apoptosis of cholestatic hearts. Cholestatic hearts also had an increased level of MDA and decreased activities of CAT and GSHPx, which were not modified by d ‐NAME treatment. By l ‐NAME treatment, the level of MDA decreased and activities of CAT, GSHPx and SOD increased in BDL mice. The content of NO was higher in cholestatic cardiac tissue, which was decreased by l ‐NAME treatment. Conclusion: In conclusion, apoptosis in cholestatic heart might have occurred because of NO overproduction, which could induce oxidative stress in the heart of cholestatic mice.  相似文献   
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Until now, cerebral venous sinus thrombosis (CVST) was principally an autopsy diagnosis; however, with the introduction of MRI and angiography, as well as enhanced clinical attentiveness, it is now reliably diagnosed during life. Herein, we describe a case of CVST accompanied by oligodendroglioma and pregnancy. In our patient, the following factors contributed to the formation of CVST: First, the pregnancy state, which is a known risk factor for developing venous thrombosis; and secondly, the oligodendroglioma could have changed the architecture of adjacent sinus (right lateral sinus) and provocation of the development of clot in the sinus.  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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