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991.
Recent studies demonstrate a requirement for the Extracellular signal Regulated Kinase (ERK) mitogen-activated protein kinase (MAPK) cascade in both the induction of long-lasting forms of hippocampal synaptic plasticity and in hippocampus-dependent associative and spatial learning. In the present studies, we investigated mechanisms by which ERK might contribute to synaptic plasticity at Schaffer collateral synapses in hippocampal slices. We found that long-term potentiation (LTP) induced with a pair of 100-Hz tetani does not require ERK activation in mice whereas it does in rats. However, in mice, inhibition of ERK activation blocked LTP induced by two LTP induction paradigms that mimicked the endogenous θ rhythm. In an additional series of studies, we found that mice specifically deficient in the ERK1 isoform of MAPK showed no impairments in tests of hippocampal physiology. To investigate ERK-dependent mechanisms operating during LTP-inducing stimulation paradigms, we monitored spike production in the cell body layer of the hippocampus during the period of θ-like LTP-inducing stimulation. θ-burst stimulation (TBS) produced a significant amount of postsynaptic spiking, and the likelihood of spike production increased progressively over the course of the three trains of TBS independent of any apparent increase in Excitatory Post-Synaptic Potential (EPSP) magnitude. Inhibition of ERK activation dampened this TBS-associated increase in spiking. These data indicate that, for specific patterns of stimulation, ERK may function in the regulation of neuronal excitability in hippocampal area CA1. Overall, our data indicate that the progressive increase in spiking observed during TBS represents a form of physiologic temporal integration that is dependent on ERK MAPK activity.  相似文献   
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994.
Previous research has suggested that black Americans tend to view mental health services and community mental health centers more negatively than do white Americans. This article discusses a recent study that sought to determine whether black persons possess positive or negative attitudes, what factors influence attitude formation, and the implications of these findings. Based on a sample of black residents in a city in the Northeast, the study found that fewer than 20% of black persons possess negative attitudes toward community mental health centers, that 34% possess positive attitudes, that women and married persons tend to possess more positive attitudes than do men and unmarried persons, that those with high levels of racial consciousness tend to possess more positive attitudes than those who do not, and that those with a high tolerance of substance use tend to possess more negative attitudes than do less tolerant persons. The author suggests that human service agencies should educate social and health workers to become more aware of the cultural diversity and attitudes of the black community so that they may more effectively serve black clients.  相似文献   
995.
Philosophical Studies -  相似文献   
996.
There appear to be at least two kinds of compound physical substances: compound pieces of matter, which have their parts essentially, and living organisms, which do not. Examples of the former are carbon atoms, salt molecules, and pieces of gold; and examples of the latter are protozoa, trees, and cats. Given that there are compound entities of these two kinds, and given that they can be created or destroyed by assembly or disassembly, questions naturally arise about the nature of the causal relations which unite their parts. In answer to these questions, we first argue that the parts of a compound piece of matter are connected via a relation of dynamic equilibrium of attractive and repulsive forces. We then argue that the parts of an organic living thing are united in a different way: they are functionally connected in a broadly Aristotelian sense which is compatible with an ultimately non-teleological, naturalistic biology.  相似文献   
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998.
The paper surveys aspects of Islamic decision‐making within the United Kingdom's Muslim communities, in terms of the approaches towards different priority issues including ‘family values’, leadership, and inter‐Muslim relations. Fieldwork interviews incorporate diverse perspectives within different communities, in particular those seeking to approach the interpretation of Islamic primary sources in the minority, secularizing context of the UK.  相似文献   
999.
Relations between psychological adjustment and physical attractiveness were examined longitudinally in substance abuse inpatients, controlling for the effects of length of drug abuse, length of inpatient stay, age, and socioeconomic status. Measures of adjustment and attractiveness were obtained during the first week of admission and six weeks later (within two weeks of discharge). Regression analyses indicated that initial attractiveness did not predict later adjustment, and initial adjustment did not predict later attractiveness. Partial correlation analyses revealed a positive association between attractiveness and adjustment at the first time point, but not at the later time point. These results suggest that physical attractiveness exerts only a temporary effect on judgments of adjustment in an inpatient setting. Attractiveness may affect decisions made when screening patients at mental health facilities, but may not affect decisions made over the full course of inpatient treatment.  相似文献   
1000.
Summary Three experiments were conducted to examine the effect of temporospatial discontinuity on route learning. Discontinuity was created by showing subjects in a route-learning task a set of environmental scenes comprising a route in scrambled, rather than logically sequenced, order. Results from Experiments 1 and 2 indicated that discontinuity during learning affected the accuracy and the quantity of the route knowledge acquired, but suggested that the processes underlying acquisition were relatively robust. Results from Experiment 3 suggested that learning routes under conditions of discontinuity leads to a greater exaggeration of distance between route segments than is the case without discontinuity.  相似文献   
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