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1.
Adrenal chromaffin cells in vitro respond to nerve growth factor (NGF) by expressing neuronal traits. Low frequency magnetic (LFM) field stimulation, while inducing a variety of effects on several cell types, has never been studied as to its effects on chromaffin cell cultures. The purpose of this study was to compare the effects of LFM field stimulation with that of NGF on the morphological phenotype, on noradrenaline (NA) release, and on membrane excitability of cultured chromaffin cells. We also tested the effects of grafting LFM and NGF-treated chromaffin cells into the caudate nucleus of rats with 6-hydroxydopamine lesions of the nigrostriatal pathway. The results of this study showed that LFM field stimulation produced neurite growth of cultured chromaffin cells in a manner similar to that of NGF exposure. The combination of the two procedures did not induce changes above those observed by NGF alone. Both NGF- and LFM-treated chromaffin cells released [3H]NA equally in response to a depolarizing concentration of KCl. On the other, Na+ current density of LFM field stimulation increased, but to a lesser extent than that seen in NGF-treated cells. In addition both types of cells when transplanted into nigrostriatal-lesioned animals induced a similar decrease in the motor asymmetries produced by the lesion. When NGF- or LFM-treated chromaffin cells where compared to untreated control cells, no significant differences were observed in [3H]NA release, on Na+ current densities, or on postgraft motor asymmetries. The results are discussed in terms of the fact that LFM-stimulated cells can be differentiated in a manner similar to NGF-treated cells, by acquiring sympathetic like traits which in turn can diminish motor asymmetries when grafted into nigrostriatal-lesioned rats.  相似文献   
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This study hypothesized that family role (marital and parental status) would moderate the effect of disaster exposure on the mental health of victims. The study included St. Louis residents exposed to floods and dioxin, as well as Puerto Rican respondents exposed to floods and mudslides. In St. Louis, worst outcomes were found for single and married parents exposed to disaster, substantially exceeding the symptomatology of all unexposed respondents except non-victim single parents. In Puerto Rico, victims without families had higher levels of alcohol abuse symptoms than did any other subgroup. Perceived emotional support was found to be an important moderator of disaster's effect on psychiatric distress in this site, generally overriding the effect of family role. Single parents in both sites who were exposed to disaster had substantially reduced levels of emotional support available to them, as compared to unexposed single parents, suggesting that single parents are at particularly high risk for losing access to emotional support following a disaster. This study suggests that both single and married parents constitute important high-risk victim groups. The findings also suggest that those perceiving they lack adequate emotional support, regardless of family role, may be in special need of services.  相似文献   
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Community-academic partnerships in the training of doctors offer unique learning opportunities of great importance. Such partnerships can induce a paradigm shift such that physicians view community as a teaching resource and partner rather than as a passive recipient of services or solely as a placement site. The authors describe a model of a community-academic partnership in New York City, begun in 1995, in which, for training and service, pediatric residents are integrally involved in a community-based program. Principles adapted from the Community-Campus Partnerships for Health's principles of partnership provide a framework for portraying the essential elements of developing and maintaining the partnership. The authors explain the clashes that may arise between partners and show how the principles of partnership guide partnership members in working and learning within a setting that by its nature entails conflict and inequality. This report is based on the knowledge gained from the structured reflections of both members of this partnership: the residency program at a large academic health center and the community-based social service organization. Such partnerships provide the training ground for the development of physicians who understand the social and cultural determinants of health and constructively use community agencies' input in promoting child health and well-being. Within this framework, community-based organizations are not solely service providers but become educators of physicians-in-training who, with new knowledge gained through the partnership, more effectively contribute to the overall health of the communities they serve.  相似文献   
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The influence of dietary choline availability on cognition is currently being suggested by animal and human studies which have focused mainly on the early developmental stages. The aim of this review is to systematically search through the available rodent (rats and mice) research published during the last two decades that has assessed the effect of dietary choline interventions on cognition and related attentional and emotional processes for the entire life span. The review has been conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement guidelines covering peer-reviewed studies included in PubMed and Scopus databases. After excluding duplicates and applying the inclusion/exclusion criteria we have reviewed a total of 44 articles published in 25 journals with the contribution of 146 authors. The results are analyzed based on the timing and duration of the dietary intervention and the behavioral tests applied, amongst other variables. Overall, the available results provide compelling support for the relevance of dietary choline in cognition. The beneficial effects of choline supplementation is more evident in recognition rather than in spatial memory tasks when assessing nonpathological samples whilst these effects extend to other relational memory tasks in neuropathological models. However, the limited number of studies that have evaluated other cognitive functions suggest a wider range of potential effects. More research is needed to draw conclusions about the critical variables and the nature of the impact on specific cognitive processes. The results are discussed on the terms of the theoretical framework underlying the relationship between the brain systems and cognition.  相似文献   
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IntroductionNECPAL is a tool for identification of patients with advanced chronic disease in need of palliative care. The main objective of the study is to know the prevalence of patients with palliative needs in an acute respiratory ward in a Spanish tertiary hospital using NECPAL. A second objective of the study is to know the annual mortality rate of these patients.Materials and methodsCross sectional study and prospective monitoring of a cohort identified as palliative patients with the NECPAL tool for 12 months. Patient identification was performed in patients admitted to the respiratory ward of our hospital for longer than 3 days. We have assessed the annual vital status (deceased or not deceased) of patients and have recorded demographics, clinical and functional data, as well as the use of healthcare resources.ResultsWe monitored a cohort of 363 patients. Of them, 87 patients (24.3%) (IC 95% 19–30) were identified as NECPAL positive. 60% of patients (n = 64) died within 12 months of their admission. There was no significant difference in the mortality ratio of oncologic versus non oncologic patients. In a multivariable analysis, mortality was associated with demand by patients or relatives for palliative care and with the presence of specific disease progression markers or indicators.Conclusionsprevalence of patients with palliative needs in acute respiratory wards is high (one out of four patients). 60% of the patients identified as NECPAL positive in our cohort died in the first 12 months. Training of healthcare professionals as well as availability of appropriate resources are indispensable factors to improve care of this population.  相似文献   
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