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OBJECTIVE: Smoking is an important environmental risk factor for the initiation and progression of periodontal diseases. The aim of this study was to evaluate the effects of smoking on clinical parameters and the gingival crevicular fluid (GCF) contents of the pro-inflammatory cytokines interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) levels in patients with chronic periodontitis. MATERIAL AND METHODS: The study base consisted of 41 patients including 22 volunteer current smokers with an age range of 32-59 (44.41+/-7.88) years and 19 volunteer non-smokers with an age range of 36-59 (46.94+/-6.07) years. The first month after non-surgical periodontal therapy was accepted as the baseline of the study. The clinical parameters including plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), clinical attachment loss (CAL) were recorded and GCF samples were collected for analysis of GCF contents of IL-6 and TNF-alpha levels. At the 3rd and 6th months, all of these procedures were repeated. RESULTS: In smokers, only CAL was significantly higher at the 3rd month compared with non-smokers (p<0.05). GI and BOP were higher in non-smokers than smokers in both periods (p<0.05). PI showed increases from the initial to the 6th month in smokers (p<0.05). Although the differences between two groups with regard to IL-6 and TNF-alpha were not significant (p>0.05), the total amount of TNF-alpha in GCF decreased from the initial to the 6th month in smokers (p<0.05). There were no significant correlations between the mean total amount of IL-6 and TNF-alpha in GCF and clinical parameters in both evaluation periods in smokers (p>0.05). CONCLUSION: The present study demonstrated that cigarette smoking increases the amount of dental plaque over time in smokers and does not influence GCF contents of IL-6 and TNF-alpha.  相似文献   
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OBJECTIVES: Neopterin is produced by stimulated macrophages under the influence of gamma interferon of lymphocyte origin. It is regarded as a biochemical marker of cell-mediated immune response. This study was designed to assess the diagnostic value of pleural fluid neopterin levels in tuberculous pleurisy in comparison with adenosine deaminase activity. DESIGN AND METHODS: Pleural fluid adenosine deaminase (ADA) activity and neopterin levels were measured in 16 patients with tuberculous pleurisy (TP) and 19 patients with malignant pleurisy (MP). ADA activity was determined by a colorimetric method, whereas neopterin levels were determined by a reversed-phase liquid chromatography technique. All values were given as median (min-max). RESULTS: The mean age was 45.43+/-20.39 years in the TP group and 60.42+/-11.02 years in the MP group (p=0.026). The median pleural fluid ADA activity was 51.75 U/L (3.50-62.40 U/L) in the TP group and was 2.30 U/L (1-8.20 U/L) in the MP group. The difference was statistically significant (p<0.001). The median pleural fluid neopterin levels were 13.15 nmol/L (1.86-59.50 nmol/L) and 2.44 nmol/L (0.92-27.60 nmol/L) in the TP group and the MP group, respectively (p=0.021). In order to evaluate the diagnostic value of pleural fluid neopterin concentrations, receiver-operating-characteristic curve analysis was performed. CONCLUSION: Pleural fluid neopterin concentration is significantly higher in TP when compared to MP, however when compared, its clinical use as a diagnostic marker is not valuable as ADA.  相似文献   
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A prospective analysis was conducted comparing dysfunction attributable to catheter thrombosis in subjects who received a heparin catheter lock three times a week (n = 15) to those who received a heparin lock six times a week (n = 15) immediately after the insertion of a temporary haemodialysis catheter. Thrombus related catheter removal occurred in two patients in control but no patients in the experiment group. Heparin locking six times a week was found to be effective in prolonging the mean of the first day where difficulty was experienced in aspiration. It also prevented any possible difficulty in catheter flushing. Increased locking frequency prevents any thrombus accumulation within the temporary catheter, while it has limited but significant preventive effect on thrombus accumulated around the catheter.  相似文献   
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In this multicenter retrospective analysis, we aimed to present clinical, laboratory and treatment results of 94 patients with Hairy cell leukemia diagnosed in 13 centers between 1990 and 2014. Sixty‐six of the patients were males and 28 were females, with a median age of 55. Splenomegaly was present in 93.5% of cases at diagnosis. The laboratory findings that came into prominence were pancytopenia with grade 3 bone marrow fibrosis. Most of the patients with an indication for treatment were treated with cladribine as first‐line treatment. Total and complete response of cladribine was 97.3% and 80.7%. The relapse rate after cladribine was 16.6%, and treatment related mortality was 2.5%. Most preferred therapy (95%) was again cladribine at second‐line, and third line with CR rate of 68.4% and 66.6%, respectively. The 28‐month median OS was 91.7% in all patients and 25‐month median OS 96% for patients who were given cladribine as first‐line therapy. In conclusion, the first multicenter retrospective Turkish study where patients with HCL were followed up for a long period has revealed demographic characteristics of patients with HCL, and confirmed that cladribine treatment might be safe and effective in a relatively large series of the Turkish study population. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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The current positron emission tomography (PET) design is aimed toward establishing an entire-body PET scanner. An entire-body PET scanner is a scanner whose axial field of view (FOV) covers the whole body of a patient, whereas whole-body PET scanner can be of any axial FOV length, but was designed for a whole-body scan. Despite its high production cost, an entire-body depth-of-interaction PET scanner offers many benefits, such as shorter and dynamic PET time acquisition, as well as higher sensitivity and count rate performance. This PET scanner may be cost-effective for clinical PET scanners with high scan throughput. In this work, we evaluated the sensitivity and count rate performance of a 2-m-long PET scanner with conventional data acquisition (DAQ) architecture, using Monte Carlo simulation, and we evaluated two ring diameters (60 and 80 cm) to reduce the scanner cost. From simulation of scanning with a 2-m axial FOV, the sensitivity for a 2-m-long PET scanner of 60 and 80-cm diameter is around 80 and 68 times higher, respectively, than that of the conventional PET scanner. In addition, for the 2-m-long PET scanner with 60-cm diameter, the peak noise equivalent count rate (NECR) was 843 kcps at 125 MBq, whereas the peak for the 80-cm diameter was 989 kcps at 200 MBq. This shows gains of 15.3 and 17.95, respectively, in comparison with that of the conventional PET scanner. The 2-m-long PET scanner with 60-cm ring diameter could not only reduce the number of detectors by 21 %, but also had a 17 % higher sensitivity compared to that with an 80-cm ring diameter. On the other hand, despite the higher sensitivity, the NECR of the 60-cm ring diameter was smaller than that of the 80-cm ring diameter. This results from the single data loss due to dead time, whereas grouping of axially stacked detectors was used in the conventional DAQ architecture. Parallelization of the DAQ architecture is therefore important for the 2-m-long PET scanner to achieve its optimal performance.  相似文献   
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Much of our fundamental knowledge related to polymer networks is built on an assumption of ideal end-linked network structure. Real networks invariably possess topological imperfections that negatively affect mechanical properties; modifications of classical network theories have been developed to account for these defects. Despite decades of effort, there are no known experimental protocols for precise quantification of even the simplest topological network imperfections: primary loops. Here we present a simple conceptual framework that enables primary loop quantification in polymeric materials. We apply this framework to measure the fraction of primary loop junctions in trifunctional PEG-based hydrogels. We anticipate that the concepts described here will open new avenues of theoretical and experimental research related to polymer network structure.  相似文献   
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