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101.
This study examines University of Pennsylvania Smell Identification Test (UPSIT; R. L. Doty, 1995) performance in 133 controls and 54 chronic, medicated outpatients with schizophrenia (SZ) using item-response theory modeling. Results show that UPSIT items contribute to 1 factor, cover a range of 8 standard errors of measurement, and articulate 3 ability levels. Although it is not difficult enough to discriminate among persons of above-average ability, the test has diagnostic utility in detecting moderate impairment. Independent of item difficulty, 13 items differentiate patients from controls. When 45 patients and 45 controls were matched on gender and age, patient accuracy remained significantly reduced. The findings support the test's utility and demonstrate how traditional data analysis is insensitive to complexities in test performance.  相似文献   
102.
Three experiments investigated the effects of varying the conditioned stimulus (CS) duration between training and extinction. Ring doves (Streptopelia risoria) were autoshaped on a fixed CS-unconditioned stimulus (US) interval and extinguished with CS presentations that were longer, shorter, or the same as the training duration. During a subsequent test session, the training CS duration was reintroduced. Results suggest that the cessation of responding during an extinction session is controlled by generalization of excitation between the training and extinction CSs and by the number of nonreinforced CS presentations. Transfer of extinction to the training CS is controlled by the similarity between the extinction and training CSs. Extinction learning is temporally specific.  相似文献   
103.
A 16-element movement sequence was taught under part-whole and whole-practice conditions. Participants (N = 18) produced a right-arm lever movement to sequentially presented target locations. The authors constructed part-whole practice by providing practice on only the 1st 8 elements on the 1st day of practice (100 repetitions of the 8-element sequence) and on all 16 elements on the 2nd day of practice (100 repetitions of the 16-element sequence). The whole-practice group practiced all 16 elements on both days (100 repetitions of the 16-element sequence per day). No differences in sequence structure or in movement duration of the 16-element sequence were noted on the retention test (Day 3). On transfer tests in which the 1st and last 8 elements were tested separately, however, the participants in the part-whole practice group performed more quickly than the participants in the whole-practice group, especially on the last 8 elements. Participants in the whole-practice group appeared to code the sequence so that it was relatively difficult to fully partition it into separate movements. Thus, on the transfer tests, there continued to be residual effects of the 8 elements that did not have to be produced but slowed down the rate of responding for the whole-practice group. That finding was not observed for the part-whole practice group.  相似文献   
104.
Howard DE  Wang MQ 《Adolescence》2003,38(151):519-533
The prevalence of dating violence, as well as its association with psychosocial factors, was examined among a nationally representative sample of 9th- through 12th-grade U.S. boys (N = 7,434) who completed the 1999 Youth Risk Behavior Survey. The dependent variable was physical dating violence; the independent variables were violence, suicide, substance use, and sexual risk behavior. Unadjusted odds ratios (OR) and 95% confidence intervals (CI) were examined. Multivariate logistic regression was used to examine all significant independent variables from the univariate models. Adjusted OR and 95% CI were examined to assess the significance of these relationships. In terms of prevalence, 9.13% of the boys reported physical dating violence. Boys who reported sad/hopeless feelings (OR = 1.68), had attempted suicide (OR = 2.22), reported fighting (OR = 1.81), had multiple sex partners (OR = 3.53), and reported nonuse of condoms (OR = 1.66) were more likely to report physical dating violence. These findings indicate that physical dating violence among adolescent boys may be a more serious problem than has previously been recognized. It was concluded that intervention programs should include a focus on boys as not only perpetrators but also recipients of dating violence.  相似文献   
105.
Howard DE  Wang MQ 《Adolescence》2003,38(149):1-14
The prevalence of dating violence, as well as its relationship to potential risk factors, was examined among a nationally representative sample of 9th-through 12th-grade U.S. females (N = 7,824) who completed the 1999 Youth Risk Behavior Survey. The dependent variable was physical dating violence; the independent variables were violence, suicide, substance use, and sexual risk behavior. Unadjusted odds ratios (OR) and 95% confidence intervals were examined, and multivariate logistic regression analysis was conducted to identify the most significant risk factors. It was found that nearly one in ten of the adolescent girls reported dating violence. Twelfth-grade girls had the highest prevalence of dating violence. Girls who were victims of dating violence were more likely to be involved in other violent behaviors, to report extreme sadness and suicidal actions, to use illicit substances, and to engage in risky sexual behavior. Multivariate analysis revealed that dating violence was associated with sad/hopeless feelings (OR = 2.13), binge drinking (OR = 1.96), cocaine or inhalant use (OR = 2.90), multiple sex partners (OR = 2.38), nonuse of condoms (OR = 1.53), and ethnicity, specifically being Black (OR = 2.32) or Hispanic (OR = 1.82). These findings provide further evidence that there is a clustering of risk factors among certain adolescents, specifically girls who experience dating violence.  相似文献   
106.
Two empirically-derived scales from Furnham's Money Attitude Scale are presented. They measure money as a source of status and power and having a strong desire for money.  相似文献   
107.
We previously reported that a total methanolic extract of the underground part of Angelica gigas Nakai (Umbelliferae) (here-in-after abbreviated AG) significantly inhibited acetylcholinesterase (AChE) activity. We characterized 12 coumarin derivatives including both decursin and decursinol from extracts of AG. In this study, we evaluated the anti-amnestic activity of decursin, a major coumarin constituent isolated from AG, in vivo using ICR mice with amnesia induced by scopolamine (1 mg/kg body weight, s.c.). Decursin, when administered to mice at 1 and 5 mg/kg body weight i.p., significantly ameliorated scopolamine-induced amnesia as measured in both the passive avoidance test and the Morris water maze test. Moreover, decursin significantly inhibited AChE activity by 34% in the hippocampus of treated mice. These results indicate that decursin may exert anti-amnestic activity in vivo through inhibition of AChE activity in the hippocampus.  相似文献   
108.
Personality disorders (PDs) are usually construed as psychiatric categories characterized by a unique configuration of traits and behaviors. To generate clinical hypotheses from normal personality trait scores, profile agreement statistics can be calculated using a prototypical personality profile for each PD. Multimethod data from 1,909 psychiatric patients in the People's Republic of China were used to examine the accuracy of such hypotheses in the Interpretive Report of the Revised NEO Personality Inventory. Profile agreement indices from both self-reports and spouse ratings were significantly related to PD symptom scores derived from questionnaires and clinical interviews. However, accuracy of diagnostic classification was only modest to moderate, probably because PDs are not discrete categorical entities. Together with other literature, these data suggest that the current categorical system should be replaced by a more comprehensive system of personality traits and personality-related problems.  相似文献   
109.
Interlimb coordination is subject to constraints. One major constraint has been described as a tendency for homologous muscle groups to be activated simultaneously. Another has been described as a biasing of limb segments to movement in the same direction. In 2 experiments, the 2 constraints were placed in opposition: In-phase or antiphase contraction of homologous muscles of contralateral limbs produced movement that was spatially antiphase or in-phase, respectively. Probability distributions of relative phase were obtained under manipulations of phase detuning and movement speed. They revealed that the equilibrium and stability of coordination were related, respectively, to spatial relative phase and muscular relative phase. Previously observed spatial and muscular constraints reflect a (possibly very general) factorization of attractor location and attractor strength in the dynamics of interlimb coordination.  相似文献   
110.
本文从现代心理学角度考察了唯识学之心法八识所建构的认识结构。  相似文献   
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