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There is currently much interest in the potential impact of psychological factors on immune responses. An attempt was made to assess the effects of dominant/subordinate polarity in male mice on the cytotoxic activities of their natural-killer (NK) cells. On the basis of repeated agonistic encounters, categories of subordinate and dominat animals were selected. These animals were compared with manipulated controls (introduced to a novel test cage without an opponent on each occasion) and undisturbed controls (who remained in isolation without manipulation). In terms of NK activity, immunosuppression was observed in both dominant and subordinate categories when compared to undisturbed controls. There were, however, no differences between the fighting exposed subjects and the manipulated controls, suggesting that stress accounts for any changes. © 1994 Wiley-Liss, Inc.  相似文献   
43.
Effects of timing of social isolation on play fighting and serious fighting were studied at different ages in male golden hamsters. Litters were isolated at 21, 35, and 65 days of age, and tested in a resident-intruder paradigm. Behaviors were compared within grous and with a fourth group of socially reared conspecifics. The earlier the pups were isolated, the more they engaged in play activities. Later, in adulthood, the aggression level of the same animals was retested using the same paradigm. The three isolated groups showed a high level of aggression, with significant differences among them. When compared with socially reared subjects, a reliable difference in the level of aggression was also found. These results support the view that early social experience is important, suggesting that isolation during early critical periods of socialization has a significant impact on play fighting, whereas short periods of isolation may be enough to trigger adult agonistic behavior. © 1994 Wiley-Liss, Inc.  相似文献   
44.
This study assessed whether two types of non-aggressive “standard opponents” (“intact” and “anosmic” group-housed males) produced similar behavioral changes in isolated OF1 male mice given several experiences of victory. Experimental groups confronted either intact or anosmic opponents every two days until they had completed four encounters. The behavioral changes were recorded using a detailed ethologically inspired analysis. These changes were clearly different depending on the opponent type. When intact opponents were used, experimental subjects increased the time spent in digging, non-social exploration, explore from a distance, and attack over encounters, but showed decreased time spent in threat and a decreased latency to the first attack. In encounters with anosmic opponents, only declines in the latencies to threat and attack were noted. Moreover, the experimental groups differed in their behaviors over encounters. Those confronting intact opponents spent less time in social investigation, more time in explore from a distance and threat, and showed a shorter latencies to threat and attack than counterparts confronting anosmics. These results suggest that, although both types of “standard opponents” are similar in their non-aggressiveness, they elicit rather different behavioral responses in their adversaries. These findings provide additional support for the view that the type of opponent used in studies on intermale aggression is of paramount importance. Indeed, the use of different types of “standardized non-aggressive opponents” appears to be an important source of variability between studies. © 1994 Wiley-Liss, Inc.  相似文献   
45.
There is a frequent need to measure the degree of agreement among R observers who independently classify n subjects within K nominal or ordinal categories. The most popular methods are usually kappa-type measurements. When = 2, Cohen's kappa coefficient (weighted or not) is well known. When defined in the ordinal case while assuming quadratic weights, Cohen's kappa has the advantage of coinciding with the intraclass and concordance correlation coefficients. When > 2, there are more discrepancies because the definition of the kappa coefficient depends on how the phrase ‘an agreement has occurred’ is interpreted. In this paper, Hubert's interpretation, that ‘an agreement occurs if and only if all raters agree on the categorization of an object’, is used, which leads to Hubert's (nominal) and Schuster and Smith's (ordinal) kappa coefficients. Formulae for the large-sample variances for the estimators of all these coefficients are given, allowing the latter to illustrate the different ways of carrying out inference and, with the use of simulation, to select the optimal procedure. In addition, it is shown that Schuster and Smith's kappa coefficient coincides with the intraclass and concordance correlation coefficients if the first coefficient is also defined assuming quadratic weights.  相似文献   
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A recent re-operationalisation of grandiose narcissism has resulted in the distinction of two narcissistic strategies based on the cognitive, affective-motivational and behavioural dynamics: admiration (assertive self-enhancement) and rivalry (antagonistic self-protection). The Narcissistic Admiration and Rivalry Questionnaire (NARQ) was developed to assess this model with two higher-order dimensions. However, cross-validations of the NARQ have not been extensively conducted across diverse population groups and languages. This study aimed to test the internal and external validity (through the relation with envy and self-esteem), reliability and cross-cultural equivalence of the Spanish version of the NARQ. The psychometric properties were evaluated in a Spanish sample (N = 310), and cross-cultural equivalence was tested in participants from Chile (N = 234) and Colombia (N = 256). The results supported the reliability and validity of the Spanish NARQ, as well as the cross-cultural equivalence across Spanish-speaking countries. In addition, we discuss obtained differences across Spanish, Chilean and Colombian sample within two narcissistic strategies.  相似文献   
48.

Until this research, correlation of Rosenberg’s (1965) self-esteem scale (RSES), with religious and spiritual values, was never investigated using the measure as a twofold construct instead of the monolithic form. This research paper explores the prediction of RSES by spiritual values using a twofold structure of: self-esteem-positive (SEP) and self-esteem-negative (SEN), to specify individual and fragmented correlations with spirituality, which until now was unobtainable. Confirmatory factor analysis and structural equation modelling were applied to analyse the data. The survey was conducted among two-hundred and sixty-eight participants from the Republic of Ireland. The research finds that spirituality influences peoples’ self-esteem, but clear and linear correlation between spirituality and self-esteem is difficult to be concluded. People respond oppositely and differently to positive and to negative items in the RSES which indicates that the measure is a combination of two statistically consistent constructs: SEP and SEN. The results of the study confirm that there are many spiritual areas that affect self-esteem.

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49.

In 1950s, the concept of brain death, which began to be discussed primarily in terms of medicine and then in terms of religion, law, and ethics, became a central topic in all world countries as it was an early diagnosis of death. Despite the fact that brain death (BD) diagnosis is of importance for benefitting from organ and tissue transplantation of patients in the world, the literature still involves no bibliometric studies that made a holistic evaluation of the publications about this issue. The present study aims to investigate the top-cited articles about BD published between 1980 and 2018, identify the citation collaboration of the journals, demonstrate the collaboration between the countries, define the relationship between organ transplantation and BD, and reveal the latest developments and trend topics about this issue. In addition, this study aims to investigate the relationship between religions of countries and brain death publication productivity. Documents for bibliometric analysis were downloaded from Web of Science. The literature search was performed using the keywords “brain death/dead” during 1980–2018. The correlations between gross domestic product (GDP), Human Development Index (HDI) and publication productivity of the countries on BD were investigated with Spearman’s correlation coefficient. There was a high-level, statistically significant correlation between the number of publications and GDP, and HDI and the number of publications about BD (r = 0.761, p < 0.001; r = 0.703, p < 0.001). The USA was the top country in terms of publication productivity, which was followed by developed countries such as Germany, Japan, France, and Spain. However, the contribution of the undeveloped or developing countries such as China, Brazil, Turkey, Iran, and South Africa was found to be considerably important. While many people in the world die with undamaged organs, many other people die needing those organs. Therefore, it is considered that the collaborations and thus multidisciplinary studies about BD should be increased in the world countries, and the countries should be involved in bigger collaborations instead of little clusters. Especially, Muslim countries should be encouraged to do research and publish studies about the issues of brain death and organ transplantation.

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50.
Social networking sites (SNSs) enrol new subscribers each day. However, problematic SNS use has undesirable effects on psychological functioning. Therefore, it is important to identify the factors that contribute to the development of problematic SNS use. Very few studies have focused on revealing the underlying mechanisms of problematic SNS use. Although many past studies have examined the relationship between metacognitive beliefs and Internet addiction, the association between metacognitive beliefs and problematic SNS use has not been adequately explored. In this study, we aimed to explore the association between metacognitive beliefs and problematic SNS use among young adults. A total of 308 individuals participated in this study. A socio-demographic data form, the Metacognitions Questionnaire-30 (MCQ-30), and Social Media Addiction Scale (SMAS) were administered. Group comparisons were performed using multivariate analysis of covariance. Pearson's correlational and multiple linear regression analyses were conducted to examine the associations between metacognitive beliefs and problematic SNS use. The SNS addicts scored higher in all of the SMAS assessments. When compared to non-addicts, SNS addicts obtained higher scores on all the subtests of the SMAS and MCQ-30 except cognitive self-consciousness. The negative beliefs about the uncontrollability and danger of worry, cognitive confidence, and need for control thoughts were associated with SMAS mood modification, relapse and conflict subdimensions. Our findings revealed that dysfunctional metacognitive beliefs are related to problematic SNS use among young adults. These findings indicate that mental health workers should consider the modification of metacognitive beliefs in the treatment of problematic SNS use.  相似文献   
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