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Acute, monophasic experimental allergic encephalomyelitis (EAE) in the Lewis rat shows pathological similarities to the human disease multiple sclerosis (MS). Rats that recover from EAE are essentially resistant to disease reinduction, unlike MS in which relapses are frequently associated with common bacterial and viral infections. As macrophage-derived interleukin (IL)-12 is a critical component of innate resistance to bacterial infection and appears to directly activate encephalitogenic T cells in vivo, the ability of this cytokine to reinduce paralysis in EAE was examined. Paralytic disease was exacerbated by intraperitoneal IL-12 administration and could be reinduced up to 1 week after recovery from the primary clinical episode. Concomitant with worsening of initial clinical signs and relapse was an increase in the ratio of macrophages to T cells in brain stem perivascular cuffs and the expression of inducible nitric oxide synthase in cells with both macrophage and microglial morphology. These findings suggest that IL-12 may contribute to macrophage-mediated disease exacerbation and relapse in patients with MS.  相似文献   
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Retraction: The following article from the Journal of the Science of Food and Agriculture , ‘Temperature affects flavour intensity and quality of aroma in fresh basil (Ocimum basilicum L.) leaves’ by Xianmin Chang, Peter G Alderson, Tracey A Hollowood, Louise Hewson, and Charles J Wright, published online on 19 October 2005 in Wiley InterScience (www.interscience.wiley.com), has been retracted by agreement between the authors, the journal Editor in Chief, David S. Reid and John Wiley & Sons, Ltd. The retraction has been agreed due to overlap between this article and the following article published in the The Journal of Horticultural Science & Biotechnology ; ‘Effect of temperature integration on the growth and volatile oil content of Basil (Ocimum basilicum L.)’ by Xianmin Chang, Peter G Alderson and Charles J Wright. Volume 80 Issue 5, 2005, pages 593 – 598  相似文献   
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Although the importance of the father for the development of the child is well known and although an increased presence of the father in the family system is often demanded, processes of active shutting out the father occur. The deterioration of relation between father and child is not seen as a result of pathological male personality, but rather as a result of family or couple system. The special situation for counsellors of such cases is discussed.  相似文献   
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Npt2 encodes a renal-specific, brush-border membrane Na+-phosphate (Pi) cotransporter that is expressed in the proximal tubule where the bulk of filtered Pi is reabsorbed. Mice deficient in the Npt2 gene were generated by targeted mutagenesis to define the role of Npt2 in the overall maintenance of Pi homeostasis, determine its impact on skeletal development, and clarify its relationship to autosomal disorders of renal Pi reabsorption in humans. Homozygous mutants (Npt2(-/-)) exhibit increased urinary Pi excretion, hypophosphatemia, an appropriate elevation in the serum concentration of 1,25-dihydroxyvitamin D with attendant hypercalcemia, hypercalciuria and decreased serum parathyroid hormone levels, and increased serum alkaline phosphatase activity. These biochemical features are typical of patients with hereditary hypophosphatemic rickets with hypercalciuria (HHRH), a Mendelian disorder of renal Pi reabsorption. However, unlike HHRH patients, Npt2(-/-) mice do not have rickets or osteomalacia. At weaning, Npt2(-/-) mice have poorly developed trabecular bone and retarded secondary ossification, but, with increasing age, there is a dramatic reversal and eventual overcompensation of the skeletal phenotype. Our findings demonstrate that Npt2 is a major regulator of Pi homeostasis and necessary for normal skeletal development.  相似文献   
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The dissolution of sulphur in copper oxides leads to modifications of the ionic and electronic defect structures, causing anion and cation mobilities and possibly the electron hole concentration to be increased. No clear explanation or mechanism for these effects is available so far. The increased creep rate in the presence of sulphur dioxide as well as the variations of the electrical conductivity and the thermoelectric effect require further study for a reasonable interpretation. The formation of SO3 may play some role when oxygen and sulfur dioxide are present simultaneously.  相似文献   
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Child pedestrian injuries are often investigated by means of ecological studies, yet are clearly part of a complex spatial phenomena. Spatial dependence within such ecological analyses have rarely been assessed, yet the validity of basic statistical techniques rely on a number of independence assumptions. Recent work from Canada has highlighted the potential for modelling spatial dependence within data that was aggregated in terms of the number of road casualties who were resident in a given geographical area. Other jurisdictions aggregate data in terms of the number of casualties in the geographical area in which the collision took place. This paper contrasts child pedestrian casualty data from Devon County UK, which has been aggregated by both methods. A simple ecological model, with minimally useful covaraties relating to measures of child deprivation, provides evidence that data aggregated in terms of the casualty's home location cannot be assumed to be spatially independent and that for analysis of these data to be valid there must be some accounting for spatial auto-correlation within the model structure. Conversely, data aggregated in terms of the collision location (as is usual in the UK) was found to be spatially independent. Whilst the spatial model is clearly more complex it provided a superior fit to that seen with either collision aggregated or non-spatial models. Of more importance, the ecological level association between deprivation and casualty rate is much lower once the spatial structure is accounted for, highlighting the importance using appropriately structured models.  相似文献   
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The use of e‐assessment methods raises important concerns regarding the reliability and validity of these methods. Potential threats to validity include mode effects and the possible influence of computer‐related attitudes. Although numerous studies have now investigated the validity of online assessments in noncourse‐based contexts, few studies have addressed this issue in an educational context. The present study helps fill this research gap by investigating whether university students' computer‐related attitudes and assessment mode preferences were related to performance on a course‐based online assessment task. Overall, students' attitudes and preferences bore no greater relationships to performance on the online than offline module assessment tasks. This provides support for the validity of course‐based online assessment methods and should help alleviate educators' concerns and encourage more widespread adoption of these methods, helping address the issue of their slow uptake to date. Suggestions for follow‐up studies to corroborate and extend the current findings are offered.  相似文献   
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