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31.
Journal of Digital Imaging - Several noise sources, such as the Johnson–Nyquist noise, affect MR images disturbing the visualization of structures and affecting the subsequent extraction of...  相似文献   
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Objectives To improve the diagnosis of human fascioliasis caused by Fasciola hepatica and Fasciola gigantica, we evaluated the diagnostic accuracy of an enzyme‐linked immunosorbent assay (ELISA), with Fasciola antigen from the adult liver fluke, for the detection of IgG against fascioliasis in human sera. Methods The sera of 54 fascioliasis cases, originating from three endemic areas, were used in this evaluation: (i) a hyperendemic F. hepatica area where humans usually shed a great number of parasite eggs in faeces (11 sera); (ii) an epidemic F. hepatica area where humans usually shed small amounts of parasite eggs (24 sera) and (iii) an overlap area of both Fasciola species and where human shedding of parasite eggs in faeces is usually scarce or non‐existent (19 sera). One hundred and sixty‐eight patients with other parasitic infections and 89 healthy controls were also analysed. Results The respective sensitivity and specificity of this assay were 95.3% (95% confidence intervals, 82.9–99.2%) and 95.7% (95% confidence intervals, 92.3–97.5%). No correlation between egg output and the OD450 values of the F. hepatica IgG ELISA test was observed. Conclusions This test could be used both as an individual serodiagnostic test for human fascioliasis when backed up by a compatible clinical history together with a second diagnostic technique for other cross‐reactive helminth infections, and in large‐scale epidemiological studies of human fascioliasis worldwide.  相似文献   
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Introduction

The haemostatic system plays an important role in the process of cancer development and spread. Anticoagulants, mainly low molecular weight heparins, could prolong survival in cancer patients, particularly in patients with lung cancer, beyond prevention of thromboembolic events.

Methods

In a multicenter, investigator-initiated, open-label, randomized, sequential study, 38 patients with newly-diagnosed, limited-stage small-cell lung cancer were randomized to receive standard chemoradiotherapy or the same therapy plus 3,500 IU daily of bemiparin for a maximum of 26 weeks. The primary outcome was progression-free survival.

Results

The study was terminated early due to slow recruitment. Median progression-free survival was 272 days with chemoradiotherapy alone and 410 days in the bemiparin group; hazard ratio, 2.58 (95% confidence interval [CI], 1.15-5.80); p = 0.022. Median overall survival was 345 days with chemoradiotherapy alone and 1133 days in the bemiparin group; hazard ratio, 2.96 (95% CI, 1.22-7.21); p = 0.017. The rate of tumor response was similar in both study arms. There was no significant between-group difference in the rates of major bleeding. Toxicity related with the experimental treatment was minimal.

Conclusion

The addition of bemiparin to first line therapy with chemoradiotherapy significantly increases survival in patients with newly-diagnosed, limited-stage small-cell lung cancer. (Funded by the Instituto Científico y Tecnológico, University of Navarra. ClinicalTrials.gov identifier: NCT00324558).  相似文献   
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The purpose of this study was to investigate the relationship between P gingivalis, T forsythia, T denticola, P intermedia, and A. actinomycetemcomitans in the sulci or pockets of patients with gingivitis (G), mild chronic periodontitis (MiCP), moderate chronic periodontitis (MoCP) and severe periodontitis (SP), and the expression of TNF-alpha in gingival tissue associated with clinical parameters. Six patients with G, 7 with MiCP, 23 with MoCP and 7 with SP were recruited. Pathogens obtained from the sulci or pockets were identified by PCR, and expression of TNF-alpha from gingival tissue was analysed Probing depth (PD), clinical attachment level (CAL) and loss of bone were recorded. P gingivalis was detected at the following rates: 16.6% in subjects with G 57.1% in MiCP 57.8 % in MoCP and 58.1% in SP (p < 0.05). P intermedia was not identified in subjects with G A. actinomycetemcomitans was only identified in subjects with MoCP (31.5%) and SP (42.8%). T denticola and T forsythia were identified in all subject groups. Bacterial combinations were identified as follows: P denticola + P intermedia and PR intermedia + T forsythia were associated (p = 0.04, p = 0.02) with the presence of TNF-alpha mRNA in 20% and 25% of subjects, respectively. P gingivalis + A. Actinomycetemcomitans andA. actinomycetemcomitans + T forsythia were associated with severe PD and CAL, respectively. The association between the presence of P intermedia and expression levels of TNF-alpha was significant (p = 0.05). These results indicate that the proportion of patients with P gingivalis increases with the progression of disease. We observed that the presence of P intermedia may trigger the expression of TNF-alpha and cause a worsening of the patient's clinical status.  相似文献   
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