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31.
Malaria infection induces the production of serum antibodiesto a variety of malaria antigens but the prevalence of antibodiesto any particular antigen ins typically mucb less than 100%.It has been assumed that non-responsiveness to defined antigensin malaria immune subjects is due to HLA mediated restricutionof the Immune response. In this study we have investigated therole of HLA and non-HLA genes in the antibody response to twomerozoite surface antigens (MSP1 and MSP2) and a sexual stageantigen (Pfs260/230) opf P{lasmodium falcpartum, and concludethat host genotype is not a major determinant of responsiveness.Although antibody levels vary in accordance with seasonal variationsin malaria transmission in semi-immune children, antibiody levelsremain stable in clncall immine adults.  相似文献   
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Mild cognitive impairment (MCI) defines a group of otherwise healthy elderly subjects with a markedly elevated risk of developing Alzheimer's disease (AD). In the search for biomarkers of MCI, we assessed whether MCI shares neurochemical abnormalities with AD in areas affected early in the course of the disease. As a secondary study aim, we tested to what extent neurochemical findings reflect neuropsychological deficits. Proton spectroscopy was performed in 19 MCI patients, 18 AD patients and 22 age and gender matched controls (CON) within the parietal gray and white matter (PWM and PGM) and the hippocampus (HIP). The cognitive test battery used included measures compiled by the Consortium to Establish a Registry for Alzheimer's Disease (CERAD). The N-acetyl-aspartate to creatine ratio (NAA/Cr) was significantly reduced in the HIP of MCI and AD compared with CON (p < 0.05). Only AD patients showed parietal abnormalities, namely significantly elevated myoinositol (mI/Cr and mI/NAA) in PGM, reduced NAA/Cr and elevated mI/NAA in PWM. MCI subjects were significantly impaired in categorical verbal fluency (VF) (p < 0.001) and delayed verbal recall (DVR) (p < 0.001). VF was positively correlated with hippocampal NAA/Cr (p < 0.05) and parietal mI/NAA (p < 0.05). In summary, this study demonstrates shared neurobiological hippocampal abnormalities in MCI and AD, whereas parietal lobe neurochemical profiles and functions were normal in MCI. Thus, biological evidence is provided that MCI represents a precursor stage of AD. Moreover, multivoxel 1H MRS may enable an objective staging of the neurodegenerative process underlying the age-dependent cognitive deficits eventually leading to dementia.  相似文献   
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Background: Investigating the influence of nutrition on oral health has a long scientific history. Due to recent technical advances like sequencing techniques for the oral microbiota, this topic has gained scientific interest again. A basic challenge is to understand the influence of nutrition on the oral microbiota and on the interaction between the oral bacteria, which is also statistically challenging. Methods: Log-transformed ratios of two bacteria concentrations are introduced as the basic analytic tool. The framework is illustrated by application in an experimental study exposing eleven participants to different nutrition schemes in five consecutive phases. Results: The method could be sufficiently used to analyse the interrelation between the bacteria and to identify some bacterial groups with the same as well as different reactions to additional dietary components. It was found that the strongest changes in bacterial concentrations were achieved by the additional consumption of dairy products. Conclusion: A log ratio-based analysis offers insights into the relation of different bacteria while taking specific features of compositional data into account. The presented methods allow becoming independent of the behaviour of other bacteria, which is a disadvantage of common analysis methods of compositions. The results indicate that modulations of the oral biofilm microbiota due to nutrition change can be attained.  相似文献   
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Journal of Occupational Rehabilitation - Purpose To present an overview of the evidence of the effect of job loss prevention interventions, aiming to improve work ability and decrease absenteeism...  相似文献   
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The European Journal of Health Economics - The transferability of the EU joint clinical assessment (JCA) reports for pharmaceuticals for the German benefit assessment was evaluated by...  相似文献   
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The use of PHOTOFRIN for photodynamic therapy of human gliomas has been studied by i.v. administration and laser photosensitization. Defining the uptake of PHOTOFRIN in the patient's tumor in comparison with the surrounding normal brain tissue is highly desirable for patient selection and study ofin vivo kinetics. We utilized a non-invasive approach to the detection of PHOTOFRIN uptake in brain tumors with111In-oxine radiolabeled PHOTOFRIN and external imaging and quantitation using a gamma camera. Biodistribution of111In-labeled PHOTOFRIN in 13 organs was determined in four dogs and 15 mice with gliomas.99mTc-DTPA was used as a control for nonspecific uptake. The greatest concentration of111In-PHOTOFRIN in the brain tumor occurred at 24 hours post i.v. administration. The brain tumor PHOTOFRIN uptake was seven times greater than that of normal brain. The decreased blood background at 72 hours made this the optimum time for imaging. Specific tumor tissue uptake of111In-PHOTOFRIN occurred, well beyond that resulting from blood-brain-barrier (BBB) breakdown.  相似文献   
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