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Tickborne diseases (TBDs) such as Lyme disease result in ≈500,000 diagnoses annually in the United States. Various methods can reduce the abundance of ticks at small spatial scales, but whether these methods lower incidence of TBDs is poorly understood. We conducted a randomized, replicated, fully crossed, placebo-controlled, masked experiment to test whether 2 environmentally safe interventions, the Tick Control System (TCS) and Met52 fungal spray, used separately or together, affected risk for and incidence of TBDs in humans and pets in 24 residential neighborhoods. All participating properties in a neighborhood received the same treatment. TCS was associated with fewer questing ticks and fewer ticks feeding on rodents. The interventions did not result in a significant difference in incidence of human TBDs but did significantly reduce incidence in pets. Our study is consistent with previous evidence suggesting that reducing tick abundance in residential areas might not reduce incidence of TBDs in humans.  相似文献   
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The identification of human DNA topoisomerases as cellular targets for active anti-cancer drugs has stimulated further interest in topoisomerase function in tumour biology. Topoisom-erase I and II catalytic activity is detectable in many normal and malignant tissues. However, little is known about the expression of topoisomerases in most human solid tumours. The present study evaluated topoisomerase I and II activity in biopsy samples from 86 patients with breast, lung, cervix or colon cancers. Significant intra- and inter-tumour variation in topoisomerase expression was observed. Topoisomerase I activity was relatively high in cervix and colon tumours in comparison to lung and breast cancers. Topoisomerase II activity was high in cervix, colon and lung cancers relative to breast cancer. Topoisomerase I and II activity co-segregated in individual colon tumour samples, but no correlation was observed in cervix, lung or breast tumours. The large heterogeneity in both topoisomerase I and II activity within a tumour type suggests a mechanism for variable response to topoisomerase-directed therapy. The differences in activity between tumour groups suggest that the potential efficacy of inhibitors of topoisomerase I in colon and cervical tumours may be greater than in lung and breast tumours. Future in vivo evaluation is required to establish the clinical relevance of the observed heterogeneity in topoisomerase activity.  相似文献   
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Book reviews in this article: Objectives : To investigate the moderating effect of humour as a coping strategy on the stress‐depression relationship in a group of older men. Method : Data was collected by cross‐sectional survey method. Results : Hierarchical regression analyses revealed significant main and interaction effects for stress and humour (as a coping strategy) on depression. Conclusions : The use of humour may be an effective coping strategy for older males confronted with high levels of daily stress.  相似文献   
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Synaptic pathways in neural microcircuits   总被引:7,自引:0,他引:7  
The functions performed by different neural microcircuits depend on the anatomical and physiological properties of the various synaptic pathways connecting neurons. Neural microcircuits across various species and brain regions are similar in terms of their repertoire of neurotransmitters, their synaptic kinetics, their short-term and long-term plasticity, and the target-specificity of their synaptic connections. However, microcircuits can be fundamentally different in terms of the precise recurrent design used to achieve a specific functionality. In this review, which is part of the TINS Microcircuits Special Feature, we compare the connectivity designs in spinal, hippocampal, neocortical and cerebellar microcircuits, and discuss the different computational challenges that each microcircuit faces.  相似文献   
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CONTEXT: The evaluation of training is problematic and the evidence base inconclusive. This situation may arise for 2 main reasons: training is not understood as a complex intervention and, related to this, the evaluation methods applied are often overly simplistic. METHOD: This paper makes the case for construing training, especially in the field of specialist medical education, as a complex intervention. It also selectively reviews the available literature in order to match evaluative techniques with the demonstrated complexity. CONCLUSIONS: Construing training as a complex intervention can provide a framework for selecting the most appropriate methodology to evaluate a given training intervention and to appraise the evidence base for training fairly, choosing from among both quantitative and qualitative approaches and applying measurement at multiple levels of training impact.  相似文献   
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