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81.
The EUROCARE Study is a European Union project to assemble survival data from population-based cancer registries and analyse them according to standard procedures. We investigated and compared liver, pancreatic and biliary tract cancer survival in 17 countries from 1985 to 1989. Time trends in survival over the 1978–1989 period were also investigated in 12 countries. The overall European mean 1 year relative survival was 16% for primary liver cancer, 26% for biliary tract cancer and 15% for pancreatic cancer. The corresponding 5-year relative survival was 5, 12 and 4%, respectively. Taking the European average as the reference, the relative risk (RR) of death was at least 20% higher for the three cancers in Denmark and Estonia. Survival tended to be higher in Spain for primary liver cancer and biliary tract cancer. Gender had little influence on survival whilst age at diagnosis was inversely related to prognosis. There was an improvement in 1-year relative survival rate for primary liver cancer: relative risk (RR) of 0.68 (95% confidence interval (CI) of 0.60–0.77) for 1987–1989 versus 1978–1980 and biliary tract cancer (RR 0.77, 95% CI 0.68–0.87). There was less variation in 5-year relative survival rate over time. Some intercountry survival differences for primary liver, biliary tract and pancreatic cancers exist over Europe. Differences in quality of care, in particular treatment aggressiveness, may explain some of these differences in survival. New approaches to the management of these cancers need to be found.  相似文献   
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In this article, the estimation of fatigue is implemented in the cost function of a gradient-based model predictive controller (MPC). This is a challenging problem, because calculating fatigue leads to a non-standard and discontinuous cost function. Based on a brief previous publication, in the present work the method is derived, explained, and assessed in detail. The key enablers of the proposed method are a sequential implementation of MPC, the periodic substitution of discontinuous aspects of the cost function by linear functions, and the assumption of a sufficiently infrequent switching of this substitution. Fatigue cost gradients are obtained efficiently by automatic differentiation. The method is implemented in an economic nonlinear model predictive controller (ENMPC), which optimally balances revenue and fatigue cost. This novel formulation is applicable to a very wide range of domains, and it is demonstrated here on the control of a wind turbine. The proposed ENMPC is fully parameterized by physical and monetary variables, and outperforms a conventional ENMPC based on the literature. The method is assessed by considering various metrics, including frequency spectra, damage estimation, switching, and gradient dynamics, which together provide useful insight into its main characteristics and an initial assessment of its performance.  相似文献   
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BackgroundBlood donor care and blood safety require a quick and accurate decision on the presence or absence of Human Immunodeficiency Virus (HIV) infection, based on the proper selection of blood donors, serological and molecular HIV testing as well as western blot test. The aim was investigating the possibility of inclusion of Geenius HIV 1/2 Confirmatory Assay in blood donor testing algorithm in order to shorten test time and decrease the number of indeterminate results.MethodsA total of 75 archived serum/plasma samples were tested. Their previous serological and molecular HIV results were: 3 negative samples, 7 positive samples, 65 serological indeterminate or positive but confirmatory testing and NAT negative samples.ResultsGeenius assay confirmed the presence of antibodies in all blood donors with HIV positive serology and Nucleic Acid Testing (NAT). HIV-1 gp160 and gp41 antibodies were detected in these donors, while p31 and p24 antibodies were not detected in two and three donors, respectively. HIV-2 antibodies gp36 and gp140 were not found. Blood donor with HIV indeterminate or positive serology but negative confirmatory testing and NAT, were negative in Geenius assay.Conclusion The results obtained are consistent with western blot results. The assay proved simple and quick to perform. Studies have confirmed the possibility of introducing Bio-Rad Geenius into a routine blood donor testing protocol.  相似文献   
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Neurological Sciences - The aim of our study was to analyze oxidative stress (OS) markers in multiple sclerosis (MS) patients during relapse and remission and to evaluate the effects of...  相似文献   
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OBJECTIVE: To determine the value of 201-thallium (201-Tl) and technetium-99m sestamibi (Tc-99m MIBI) single photon emission computed tomography (SPECT) for detecting primary undifferentiated carcinoma of nasopharyngeal type (UCNT), residual/recurrent tissue, and lymph node involvement. STUDY DESIGN AND SETTING: SPECT of head and neck was prospectively performed in 46 patients with a history of UCNT (201-Tl in 24 patients, Tc-99m MIBI in 22). CT/MRI findings, clinical follow-up, and pathohistological verification served as a gold standard for calculating sensitivity, specificity, and accuracy of each scintigraphic technique. Tumor-to-background index (T/Bg) was derived when SPECT findings were positive. RESULTS: Sensitivity of 201-Tl SPECT was 87 percent, with 78 percent specificity, 83 percent accuracy, and T/Bg of 4.05 +/- 1.50. Tc-99m MIBI SPECT had 85 percent sensitivity, 78 percent specificity, 82 percent accuracy, and T/Bg of 4.45 +/- 1.27. CONCLUSION AND SIGNIFICANCE: 201-Tl SPECT and Tc-99m MIBI SPECT are useful for detecting primary UCNT, residual/recurrent disease, and lymph node involvement. This use is particularly valuable after chemoradiotherapy when CT/MRI may be ambiguous.  相似文献   
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The purpose of this experiment was to investigate the effects of repeated exposure to methylenedioxymethamphetamine (MDMA) on responses of neurons in the nucleus accumbens of anesthetized rats to microiontophoretically-applied dopamine and serotonin. In tests conducted 1–4 days or 9–15 days following the last injection of MDMA (20 mg/kg, s.c., twice daily for 4 days), the inhibitory effects of both dopamine and serotonin on glutamate-evoked firing of nucleus accumbens cells were significantly attenuated compared to effects in control rats that were pretreated with saline injections. The inhibitory effect of the D1 receptor agonist SKF38393 was also significantly attenuated in the MDMA-pretreated rats. In contrast, the amount of inhibition of glutamate-evoked firing produced by application of GABA did not significantly differ between the MDMA-pretreated and the saline-pretreated rats. The neurotoxicity of the MDMA treatment regimen was confirmed by demonstrating that 3H-paroxetine binding was significantly decreased in the medial prefrontal cortex and the nucleus accumbens of the MDMA-pretreated rats. The mechanisms that produce the attenuated inhibitory responses to dopamine and serotonin following repeated injections of MDMA are not known. However, the results of these experiments indicate that repeated MDMA administration induces long-lasting changes in dopaminergic as well as serotonergic neurotransmission in the nucleus accumbens.  相似文献   
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