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771.
Extracellular guanine-based purines, namely the nucleotides GTP, GDP, GMP and the nucleoside guanosine, exert important neuroprotective and neuromodulator roles in the central nervous system, which may be related to inhibition of the glutamatergic neurotransmission activity. In this study, we investigated GMP effects on mice inhibitory avoidance performance and the dependence on its conversion to guanosine for such effect, by using the ecto-5'-nucleotidase specific inhibitor AOPCP. We also investigated if this conversion occurs in the central nervous system or peripherally, and if guanosine and GMP affect nociception by the tail-flick test. I.p. GMP or guanosine (7.5 mg/kg) or i.c.v. GMP (480 nmol) pretraining administration was amnesic for the inhibitory avoidance task. I.c.v. AOPCP (1 nmol) administration completely reversed the amnesic effect of i.c.v. GMP, but not of i.p. GMP, indicating that peripheral conversion of GMP to guanosine is probably relevant to this effect. AOPCP alone did not interfere with the performance. Furthermore, tail-flick measurement was unaffected by i.p. GMP and guanosine, suggesting that the amnesic effect of both purines was not due to some antinociceptive effect against the footshock used in the task. All these data together, in accordance to those previously observed in studies involving glutamate uptake and seizures reinforce the idea that guanosine is the specific extracellular guanine-based purines effector and indicate that its conversion occurs not only in the central nervous system but also peripherally.  相似文献   
772.
This study investigated state-level variation in the number of right-wing militia groups. We built on prior quantitative examinations by more carefully operationalizing theoretical concepts and testing alternative hypotheses offered to account for the etiology of social movements generally and of militias specifically. Using negative binomial regression, we found that, consistent with previous research, states with higher levels of farm job loss had more militia groups. However, in contrast to prior studies, we did not find gun culture, hospitable political climate, female empowerment, or general economic deprivation to be associated with the number of militia groups. We also found no relationship between the number of militia groups and levels of fundamentalist religious culture and minority empowerment. Our study was the first to test the effects of social disorganization on the number of militias in a state, and we found the two to be positively and significantly associated. We situate our results in the theoretical and empirical literature and outline two challenges for future research. First, scholars must operationalize variables carefully since different measures of the same theoretical concept may result in diverging conclusions. Second, since one major factor (i.e., social disorganization) found in this study to be associated with the number of militia groups in a state was examined here for the first time, it is important for researchers to continue to investigate new hypotheses.  相似文献   
773.
The Changes in Outlook Questionnaire (CiOQ; S. Joseph, R. Williams, & W. Yule, 1993) is a 26-item self-report measure that was designed to assess positive and negative changes in the aftermath of adversity. This article had 3 aims: 1st, to investigate the factor structure of the CiOQ; 2nd, to test for internal consistency reliability and convergent and discriminant validity; and, 3rd, to investigate the association between positive and negative changes in outlook, posttraumatic stress, and psychological distress. Three studies are reported. Study 1 provides evidence that positive and negative changes are statistically separable and that the 2-factor model is a better fit than the 1-factor model. Studies 2 and 3 provide evidence for internal consistency reliability, convergent and discriminant validity of the CiOQ, and its associations with posttraumatic stress and psychological distress. In conclusion, the CiOQ has much promise for research on responses to stressful and traumatic events.  相似文献   
774.
Body image disturbance has been one of the most widely studied areas in the literature on eating disorders. Some of the tasks designed to assess it have been used to estimate the sizes of specific parts of the body, whereas others have served to make estimations of overall body size. In recent years, the introduction of innovative computing procedures has allowed the two approaches to be combined and has made their application more straightforward. The program we describe here (Body Image Assessment Software, or BIAS) evaluates body image distortions and body dissatisfaction via the on-screen presentation of a scale image, the different components of which can be modified by the patient. The program was developed using Microsoft Access 2000 and Visual Basic for applications. It can be run on any computer with Windows and Microsoft Access 2000 or Microsoft Access 2000 RunTime, which makes it particularly easy to use and enables direct analysis of the recorded data through the use of applications such as SPSS.  相似文献   
775.
A decade ago, Bolger and Zuckerman (1995) incorporated personality into the study of daily life events and psychological distress. Their approach put an entirely new cast on research and theorizing in this area. In their work, they focused on the predominantly negative personality trait of Neuroticism. In this article we extend their work to include theory and measurement of positive events and indicators of well-being. Integrating these research strands offers the possibility of a comprehensive yet highly sensitive and dynamic approach to the study of emotions, stress, and health in everyday life.  相似文献   
776.
Shifts of gaze to peripheral targets were studied longitudinally, between 6 and 26 weeks corrected age, in full-term and very preterm infants with transient periventricular echogenicity (PVE). Before 10 weeks, simple shifts of gaze were faster and more frequent in preterms with PVE<14 days than in full-terms, suggesting these preterms profited from additional early visual experience. After 16 weeks, there were subtle differences between full- and preterm infants in the development of shifts of gaze requiring disengagement. The differences suggest that, after disengagement had become established, its fine-tuning occurred more slowly in the preterms. Slower fine-tuning of disengagement was not associated with duration of PVE, since it was more marked in preterms with PVE<14 days than in preterms with PVE> or =14 days. The differences in performance between full- and preterm infants were small. However, even small differences may affect the efficiency of visually guided behaviors.  相似文献   
777.
The experiment reported investigated the phenomenological consequences of Easterners' and Westerners' perspectives on the self. Two findings are consistent with the notion that Asians are more likely than Westerners to experience the self from the perspective of the generalized other. First, Eastern participants were more likely than Western participants to have third-person (as opposed to first-person) memories when they thought about situations in which they would be at the center of a scene. Second, Easterners and Westerners engaged in different sorts of projections when they read the emotional expressions of other people. Westerners were more biased than Easterners toward egocentric projection of their own emotions onto others, whereas Easterners were more biased than Westerners toward relational projection, in which they projected onto others the emotions that the generalized other would feel in relation to the participant. Implications for how phenomenological experiences could reinforce different Eastern and Western ideologies about the self and the group are discussed.  相似文献   
778.
In spite of their prevalence and persistence, why are behavioral and psychological symptoms of dementia difficult for clinicians to assess and manage? This paper provides an overview of the methodological challenges encountered in measuring behavioral disturbances of dementia. Specifically, conceptual constructs of behavioral and psychological symptoms of dementia, the strengths and weaknesses of the currently existing rating instruments, analytic methodologies, and the utility of technological devices are outlined in the service of formulating future directions in behavioral and psychological symptoms of dementia assessment research.  相似文献   
779.
Does our perception of when an event occurs depend on whether we caused it? A recent study suggests that when we perceive our actions to cause an event, it seems to occur earlier than if we did not cause it.  相似文献   
780.
Community-based participatory research (CBPR) is increasingly being used to better understand and improve the health of diverse communities. A key strength of this research orientation is its adaptability to community contexts and characteristics. To date, however, few studies explicitly discuss adaptations made to CBPR principles and processes in response to community context and partners’ needs. Using data from our CBPR study, the San Francisco Chinatown Restaurant Worker Health and Safety Project, and drawing from literature on immigrant political incorporation, we examine the links between the contexts of the Chinese immigrant worker community, adaptations made by our collaborative, and study outcomes. In particular, we explore the concepts of contexts of reception and participatory starting points, which may be especially relevant for partnerships with immigrant communities whose members have historically had lower rates of civic and political participation in the US. We discuss contextual findings such as worker partner accounts of language barriers, economic and social marginalization, and civic skills and participation, as well as subsequent adaptations made by the partnership. We also describe the relative effectiveness of these adaptations in yielding equitable participation and building partners’ capacity. We conclude by sharing lessons learned and their implications for CBPR and partnerships with immigrant communities more broadly.  相似文献   
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