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951.
Sleep in the dove Zenaida asiatica   总被引:1,自引:0,他引:1  
Electrographic and behavioral observations were made in five adult birds of the genus Zenaida asiatica. Five different vigilance states were quantitated: (1) Active waking (Aw) was characterized by constant behavioral activity; the nuchal electromyogram was tonically active with bursts associated to movements. The electroencephalographic pattern was low voltage and high frequency. (2) Quiet waking (Qw) was characterized by diminished behavioral activity and the EEG pattern was similar to that of Aw. (3) Drowsiness (D) was characterized by behavioral calm. Frequency of cerebral activity diminished progressively, but there were short periods of desynchronization corresponding to brief awakenings. (4) Slow wave sleep (SWS); during this period there was behavioral rest and EEG pattern of continuous slow waves and the nuchal EMG was tonically reduced. Spindles of sleep were not observed. (5) Paradoxical sleep (SP), behaviorally characterized by phasic manifestations consisting of noddings originated by rapid falling down of head and bursts of rapid eye movements. EEG activity was like that of waking state. EMG activity was maintained at the same level as during SWS but sometimes it decreased lightly. Total atonie was not observed. Sleep percentages were higher when recordings were done during the nocturnal period.  相似文献   
952.
ABSTRACT

In the religiously pluralized Western world, a trend called ‘Multiple Religious Belonging’ (MRB) has been identified. Although it is a much theologically debated concept, empirical research on the practice of MRB is limited. The present research project therefore explores the phenomenon of MRB among visitors of Dominican spiritual centers in the Netherlands (n=472). It investigates to what extent and in which ways such visitors combine elements from more than one religious tradition in their lives and what they perceive to be the benefits of combining elements. It links this information to their views on religion, the resources they draw from, their (religiously diverse) networks, and their motivations for attending spiritual activities. The results indicate that respondents who combine elements from more than one religious tradition (‘combiners’) are more likely than ‘non-combiners’ to: a) see religion as something that is constantly changing during the life course; b) have networks which are religiously diverse; c) place importance on nature, in-depth conversations, personal rituals or practices, and theological, philosophical, and spiritual texts as resources; d) be motivated to attend spiritual centers because of a focus on self-exploration.  相似文献   
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954.
Scopolamine effects on memory retention in mice: a model of dementia?   总被引:4,自引:0,他引:4  
Scopolamine-treated normal young human subjects exhibit memory dysfunctions analogous to those observed in demented patients. The dysfunctions are reversible by physostigmine but not by d-amphetamine which suggests that the memory impairment is specifically related to reduced cholinergic transmission caused by scopolamine. Scopolamine-induced amnesia has been proposed as a model for dementia where reduced cholinergic function is the suspected cause. We report seven experiments in young adult mice which examine scopolamine's effects on memory retention and whether its amnestic effects are specifically blocked by cholinergic agonists or cholinomimetics. Young adult mice were trained to avoid footshock in a T maze and their retention tested 1 week after training. Pretraining subcutaneous injection of scopolamine improved retention scores of "undertrained" mice at a dose of 0.01 mg/kg but impaired at a dose of 0.1 mg/kg. Post-training injection showed no effect at 0.01 mg/kg, enhanced retention scores at 0.1 mg/kg, and impaired at 1.0 mg/kg. The impairment by 1.0 mg/kg was blocked by injection 45 min post-training of each of two cholinergic drugs but was also counteracted by six drugs which act upon five other neural systems (catecholamine, serotonin, glycine, GABA, and hormonal). When scopolamine was injected 40 min pretraining, and each of eight drugs was injected immediately after training, the amnestic effect of scopolamine was only partially counteracted. This suggests that scopolamine impaired acquisition, in addition to some impairment of memory processing. This was confirmed by a direct study of acquisition rates of the avoidance response; 0.1 mg/kg of scopolamine impaired acquisition. The overall results indicate that pretraining administration of scopolamine impairs learning and to some degree memory processing. Counteracting scopolamine-induced amnesia, by either pretraining or post-training drug administration, is not specific to the cholinergic system.  相似文献   
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956.
Objective: To evaluate an intervention programme based on the Health Action Process Approach and designed to increase the intake of fruit and vegetables (F&V) among Iranian adolescents aged 13 to 18.

Design: A randomised controlled trial with three arms examined the short- (1 month) and long-term (6 months) effects of the intervention. There were two intervention groups (one included adolescents only [A group; n = 510]; the second included mothers and adolescents [M + A group; n = 462]) and a control group (n = 483). All participants were recruited from schools.

Main outcome measures: Social cognitions, self-regulatory processes and F&V intake.

Results: The intervention led to an increase in F&V intake for adolescents in the short and long terms. Adolescents in the M + A group increased their F& V intake more than adolescents in the A group. Outcome expectancies, self-monitoring, intentions, action and coping planning, perceived social support and behavioural automaticity mediated the effect of the intervention on F&V intake.

Conclusion: The theory-based intervention led to an increase in F&V intake and promoted more positive social cognitions and self-regulatory processes among Iranian adolescents. The findings also provide evidence that involving mothers in an intervention can confer additional benefit.  相似文献   

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