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51.
N-methyl-D-aspartate (NMDA) receptor/channel antagonists have previously been shown to impair spatial working memory and hippocampal long-term potentiation. The present experiment investigated the effects of a variety of doses of NMDA antagonists on a working memory task in rats involving an auditory delayed conditional discrimination. Signal detection analysis and an exponential memory decay model were used to extract independent measures of stimulus discriminability and rate of forgetting. A competitive NMDA antagonist, (CPP, 0.33, 1.0, 10.0 mg/kg, IP) produced a reduction in discriminability which was linearly related to log dose, but which was only clear at the 10 mg/kg dose. Rate of forgetting was not increased by any dose. Similar results were obtained with a non-competitive antagonist (MK-801, 0.1, 0.33 mg/kg, IP). These data suggest that doses of NMDA receptor channel antagonists sufficient to disrupt hippocampal long-term potentiation and radial arm maze performance will also disrupt delayed conditional discrimination. The effect on delayed conditional discrimination is due to a disruption of stimulus discriminability and not to an increased rate of forgetting. The extent to which these effects relate to the reported changes in hippocampal long-term potentiation and radial arm maze performance remains to be determined.  相似文献   
52.
OBJECTIVE: To examine psychosocial predictors of distress (mood disturbance, perceived stress, caregiver burden) in parents of children undergoing stem cell or bone marrow transplantation (BMT). METHOD: Measures of prior illness experiences, premorbid child behavior problems, family environment, social support, and parental coping behavior were obtained from the resident parents of 151 children prior to the children's admission for BMT. Parents subsequently completed assessments of their mood disturbance, perceived stress, and caregiving burden on a weekly basis through week +6 post-BMT, and then monthly through month +6 post-BMT. RESULTS: Significant changes were observed in parental distress across the course of BMT. After correcting for demographic and medical factors, several significant predictors of parental distress trajectories were identified, including prior parent and patient illness-related distress, premorbid child internalizing behavior problems, the family relationship dimensions of the family environment, and parental avoidant coping behaviors. Multivariable models were developed using a hierarchical modeling approach. The best-fit model accounted for approximately 50% of the variance in parental global distress. CONCLUSIONS: Subgroups of parents at higher risk for increased distress during the acute phase of transplant have been identified. These findings can help target parents who may be in greater need of intervention aimed at reducing transplant-related distress.  相似文献   
53.
It was hypothesized that anger management style (anger-in or anger-out) and hostility affect the aggravation of chronic low back pain (CLBP) through symptom-specific (i.e., lower paraspinal muscle) reactivity during stress. Subjects were 102 CLBP patients who performed mental arithmetic and an Anger Recall Interview (ARI) while trapezius and lower paraspinal EMG, SBP, DBP, and HR were recorded. Results showed anger-in × hostility and anger-out × gender interactions for lower paraspinal but not trapezius reactivity, and only during the ARI. Further analyses revealed that (1) hostility was related positively to lower paraspinal reactivity among high anger suppressors, (2) hostility was related negatively to lower paraspinal reactivity among low anger suppressors, and (3) anger expression was related positively to lower paraspinal reactivity only among men. Anger management style and hostility may contribute to the exacerbation of CLBP by influencing stress reactivity only in muscles near the site of pain or injury.  相似文献   
54.
Active-Passive Coping and Skin Conductance and Heart Rate Changes   总被引:1,自引:0,他引:1  
Sixty subjects were administered 33 tasks, selected from the Raven Progressive Matrices, in conditions that differed by type of monetary reinforcement (reward, frustration, and control group). Subjects were tested in pairs. One subject, assigned as the active one, was asked to solve a problem while the other was only a passive observer. Heart rate level and the amplitude of evoked skin conductance responses were measured. Statistical analysis detected a higher heart rate level in active versus passive subjects at the beginning stage of the experiment, as well as a faster heart rate decrease in the former versus the latter group during subsequent blocks of four tasks. Changes in skin conductance response magnitude during the ensuing task phases exhibited a descending trend in passive subjects and an ascending trend in active subjects. The monetary reinforcement manipulation was not effective. The results support a concept put forward by Fowles (1988), who maintained that tonic heart rate and skin conductance response amplitude may serve as indices of the behavioral activation system and behavioral inhibition system, respectively, as postulated by Gray's model of arousal.  相似文献   
55.
深圳市警察心理素质研究Ⅲ.心理健康与应对方式调查   总被引:28,自引:1,他引:28  
目的:探讨深圳警察的心理健康和应对方式及其与人口学特征的关系。方法:通过团体测试方式对6107名深圳警察进行症状自评量表(SCL-90)和简易应对方式问卷调查。结果:深圳警察SCL-90的总均分、阳性症状均分及l0个因子分均显著低于全国常模;其积极应对得分显著高于全国常模,而消极应对得分显著低于全国常模。深圳男性警察的躯体化、强迫、人际敏感、敌对、偏执、精神病及总均分均显著高于女性,其积极应对得分显著低于女性。36-40岁年龄段及副科级警察SCL-90多项因子分在各年龄段及各职务级别警察中得分最高;45岁以前,随着年龄的递增,积极应对和消极应对两维度的均分均相应递增。结论:年龄、性别、文化程度和职务级别的不同对深圳警察的心理健康状况和应对方式存在一定影响。积极应对有利于心理健康。  相似文献   
56.
The effect of sorbitol on Ca uptake by isolated ileal epithelial cells was investigated. Intestinal cells were isolated from rat ileum by mechanical vibration.45Ca uptake was approximately 2 times higher in cells exposed to 200 mM sorbitol ofd-alanine than in control cells. This enhancing effect of sorbitol on percentage Ca uptake decreased with increasing Ca concentrations in the incubation medium suggesting an effect on Ca entry velocity. The addition of 10 M nifedipine or 200 M verapamil to the incubation medium was devoid of any effect on Ca uptake in ileal cells, whereas 100 M trifluoperazine or chlorpromazine abolished the stimulatory effect of sorbitol. Finally, the effect of sorbitol on isolated cells was independent of a measurable change of cellular ATP content. In conclusion, the stimulatory effect of sorbitol on ileal Ca uptake is probably exerted through mechanisms other than an increase in intracellular ATP concentration. Sorbitol may enhance enterocyte Ca transport via a direct interaction with calmodulin and/or the Ca pump. It may also exert its effect through an inhibition of the basolateral Na Ca exchanger.  相似文献   
57.
The main purpose of the present study was twofold: (a) to assess the relationship between defensive hostility (high hostility/high defensiveness) and additional heart rate reactivity during active coping and (b) to determine if the construct of anger-out might lend additional, sensitivity to the predictive power of the defensive hostility model. Forty individuals were randomly assigned to complete a mental arithmetic task with or without the threat of shock. Participants also completed the Cook-Medley Hostility Inventory (Ho), the Marlowe-Crowne Social Desirability Scale (MC), and the Spielberger Anger Expression Scale. Defensive hostile subjects (high Ho/high MC) were significantly more reactive than any other subgroup. In addition, the combination of low Ho/high anger-out scores yielded a subgroup significantly less reactive than any other subgroup. These findings clarify the complex relationship of hostility and cardiovascular reactivity.  相似文献   
58.
This study examined alcohol use among seventh graders in relation to life events, daily hassles, the supportive quality of the family environment, coping, and anxiety. Four hundred twenty-five students participated, 228 girls and 197 boys. Stepwise regression and discriminant function analyses indicated that the students reported more alcohol use if they also reported more life events, more daily hassles, and more conflict in the family. A stress-buffering effect of low family conflict on life events could not be substantiated for extent of alcohol use. The results are discussed in the context of the developmental transitions of adolescence.  相似文献   
59.
高中生应对方式及其与学业成绩的关系   总被引:1,自引:0,他引:1  
目的:探讨高中生面对挫折和烦恼时应对方式的特点及其与学业成绩的关系。方法:以中学生应对方式评定问卷对649名高中生进行了调查。结果:女生比男生更倾向于采用发泄(因子均分2.4±0.7/2.7±0.7,F=23.32,P<0.01)和忍耐(3.2±0.7/3.0±0.8,F=5.08,P<0.05),而男生更倾向于采用幻想(2.4±0.9/2.1±0.8, F=15.52,P<0.01);重点中学比普通中学的高中生更多采用问题解决(3.3±0.6/3.1±0.7,F=20.85,P<0.011幻想(2.4±0.9/2.1±0.9,F=12.87,P<0.01)、退避(2.9±0.6/2.8±0.6,F=7.04,P<0.01)应对;来自城市和农村的高中生应对方式差异不显著;和睦安宁家庭气氛中的高中生采用问题解决应对显著多于偶尔争吵和经常争吵家庭中的高中生;民主型教养方式下的高中生比放任型教养方式的学生更多采用问题解决应对,权威型教养方式家庭中的高中生比民主型教养方式家庭中的高中生更多采用幻想应对。结论:高中生的应对方式存在性别差异。不同家庭气氛和不同教养方式以及学生在学业上的地位对应对方式也有一定影响,但城乡差别不明显。  相似文献   
60.
军队医科大学学员应对方式特点及心理状况调查   总被引:12,自引:0,他引:12  
目的:本研究旨在掌握军队医科大学在校学员的应对方式特点,并进一步探讨应对方式和心理健康的关系,以便为军校的心理卫生工作提供重要的理论和实践依据.方法:运用简易应对方式量表和症状自评量表(SCL-90)对军医大学的4786名在校学员进行应对策略特点和健康水平进行评估.结果:(1)军队医科大学学员在面对挫折时,有30~40%的学员采取积极应对方式,而消极应对方式采用的较少(3~28%).(2)军队医科大学学员与国内军校大学生常模比较,其心理状况较好;学员采取的应对方式特点与其心理健康水平有一定的关系.结论: 军队医科大学应加强学员应对方式的教育,以更好的提高学员的心理健康.  相似文献   
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