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911.
The focus of this review is on new insights from recent epidemiological research on cerebral palsy in preterm infants. These include: 1) a better understanding of issues related to diagnosis and classification; 2) new information about the brain abnormalities underlying cerebral palsy in preterm infants; and 3) a better understanding of biological mechanisms that may underlie previously described epidemiological associations. Ongoing efforts to improve the diagnosis and classification of cerebral palsy have been enhanced by findings from serial examinations of cohorts of very preterm infants. Cranial ultrasonography through the anterior fontanelle of very preterm infants has provided information about grossly evident brain damage, found in about one-half of preterm infants who develop cerebral palsy. Insights into the pathophysiologic basis for certain epidemiologic associations have come from studies of experimental brain damage in animals and clinical studies of neurologic disorders in adults. Much of the current epidemiological research into the causes of cerebral palsy in preterm infants has focused on two potential mechanisms of brain damage. One mechanism involves insufficient cerebral perfusion; the other, cytokine-mediated damage, potentially triggered by events such as maternal infection (e.g., intrauterine or periodontal infection), neonatal infection (e.g., sepsis and necrotizing enterocolitis), and neonatal oxygen- or ventilator-induced lung injury. In addition to the preterm infant's increased exposure to such damaging factors, the high frequency of cerebral palsy in these infants might be due, in part, to insufficient levels of developmentally regulated protective substances, such as thyroid hormone and glucocorticoids. Models of causation currently are being investigated using recently developed methods for quantifying, with small quantities of blood, biomolecules that are suspected to either promote or protect against brain damage in the neonate. Clinical investigations now under way can be expected to identify strategies to be tested in clinical trials that could lower the risk of cerebral palsy in very preterm infants.  相似文献   
912.
Underdiagnosis and undertreatment of late-life depression is common, especially in primary care settings. To help assess whether physicians attitude and confidence in diagnosing and managing depression serve as barriers to care, a total of 176 physicians employed in 18 primary care groups were administered surveys to assess attitudes towards diagnosis, treatment, and management of depression in elderly patients, (individuals over 65 years of age). Logistic regression was performed to assess the association of physician characteristics on attitudes. Nearly all of the physicians surveyed felt that depression in the elderly was a primary care problem, and 41% reported late-life depression as the most common problem seen in older patients. Physicians were confident in their ability to diagnose and manage depression, yet 45% had no medical education on depression in the previous three years. Physicians confidence in their ability to diagnose, treat, and manage depression, and their reported adequacy of training, do not appear to correspond to the amount of continuing medical education in depression, suggesting that physician overconfidence may potentially be serving as a barrier to care.  相似文献   
913.
914.
Effects of task performance and contextual performance on systemic rewards   总被引:7,自引:0,他引:7  
Evidence from 2 samples of Air Force mechanics supported the hypothesis that contextual performance affects employees' career advancement and rewards over time. Results of hierarchical regressions controlling for experience showed task performance and contextual performance each predicted systemic rewards. Each facet explained separate variance in promotability ratings over 2 years. In both samples, contextual performance explained separate variance in informal rewards but task performance did not. Task performance explained incremental variance in career advancement 1 year later but contextual performance did not. Analyses using correlations corrected for unreliability suggest these results cannot be attributed to measurement error. Contextual performance still explained separate variance in informal rewards, and task performance explained distinct variance in career advancement a year later.  相似文献   
915.
Test of the cross-cultural generalizability of a model of sexual harassment   总被引:3,自引:0,他引:3  
Sexual harassment research has been primarily limited to examination of the phenomena in U.S. organizations; attempts to explore the generalizability of constructs and theoretical models across cultures are rare. This study examined (a) the measurement equivalence of survey scales in U.S. and Turkish samples using mean and covariance structure analysis and (b) the generalizability of the L. F. Fitzgerald, F. Drasgow, C. L. Hulin, M. J. Gelfand, and V. J. Magley (1997) model of sexual harassment to the Turkish context using structural equations modeling. Analyses used questionnaire data from 336 Turkish women and 455 women from the United States. The results indicate that, in general, the survey scales demonstrate measurement equivalence and the pattern of relationships in the Fitzgerald et al. model generalizes to the Turkish culture. These results support the usefulness of the model for explaining sexual harassment experiences in a variety of organizational and cultural contexts.  相似文献   
916.
The authors used a daily diary methodology to examine over 60 days how the within-person associations among event stress, alcohol consumption, and desire to drink varied as a function of gender, positive and negative alcohol-outcome expectancies, and avoidant coping in a sample of 88 regular drinkers. Multilevel regression analyses indicated that men who more strongly anticipated positive outcomes or a sense of carelessness from drinking drank relatively more on stressful days compared with low-stress days. Similar results were found predicting desire to drink. Men who anticipated greater impairment from drinking drank relatively less on stressful days. In general, these effects did not hold for women. Little evidence was found for the predicted effects for avoidant coping style, and some results showed that avoidant coping style buffered the exacerbating effects of careless unconcern expectancies.  相似文献   
917.
An exploratory item-level full-information factor analysis was performed on the normative sample for the MMPI-2 (Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989). This method of factor analysis, developed by Schilling and Bock (Bock & Schilling, 1997) and based on item response theory, works directly with the response patterns and avoids the artifacts associated with phi coefficients and tetrachoric coefficients. Promax rotation of the factor solution organizes the clinical scale items into 10 factors that we labeled Distrust, Self-Doubt, Fitness, Serenity, Rebelliousness, Instrumentality, Irritability, Artistry, Sociability, and Self-Reliance. A comparison was made to the results of Johnson, Butcher, Null, and Johnson (1984), who performed a principal-component analysis on an item set of 550 items from the previous version of the MMPI (Hathaway & McKinley, 1943). Along with version changes and sampling differences, the essential differences between Johnson et al.'s results and ours may be attributed to differences between the Schilling and Bock method, which uses all information in the item responses, and the principal-component analysis, which uses the partial information contained in pairwise correlation coefficients. This study included 518 of the complete 567 items of the MMPI-2, versus Johnson et al.'s retention of 309 of the initially included 550 items of the previous MMPI. The full-information analysis retained all 518 initially included items and more evenly distributed the items over the 10 resulting factors, all sharply defined by their highest loading items and easy to interpret. Sampling effects and factor label considerations are discussed, along with recommendations for research that would validate the clinical utility of the implied scales for describing normal personality profiles. The full-information procedure provides for Bayes estimation of scores on these scales.  相似文献   
918.
In this article, we introduce the Multi-Motive Grid (MMG), a new diagnostic tool to measure motives with respect to their hope and fear components. The MMG combines features of the Thematic Apperception Test (TAT) with features of self-report questionnaires. Similar to the TAT, a set of 14 pictures representing a balanced set of achievement-arousing, affiliation-arousing, and power-arousing situations is presented together with a set of statements representing important motivational states. Six motive scores can be calculated: hope of success (HS) and fear of failure (FF) for the achievement motive, hope of affiliation (HA) and fear of rejection (FR) for the affiliation motive, and hope of power (HP) and fear of power (FP) for the power motive. Results of factor analyses suggest a 3-factor solution, with a general fear factor (FF, FR, FP), a factor combining the hope components of achievement and power (HS and HP), and a third factor representing HA, but the 6 a priori factors also reflect a sound structural model. Reliability data show that the internal consistency and retest reliability of the MMG scales satisfy traditional standards. External validity of the MMG has been established in all 3 motive domains. Three separate studies document that (a) individuals high in resultant achievement motivation perform better and report more flow experience, (b) individuals high in resultant power motivation profit more from a leadership training program, and (c) individuals high in resultant affiliation motivation recollect more highly memorable affiliative themes.  相似文献   
919.
Using 4 experiments, the authors examined how stereotypic information about teammates influences social loafing and compensation during collective tasks. In each experiment, participants performed better on cognitive tasks when there was a poor (vs. good) fit between the stereotypic strengths of their partner and the requirements of the task. This pattern occurred whether participants used gender stereotypes (Experiment 1) or occupational stereotypes (Experiments 2 to 4) and occurred even when participants only anticipated working on a collective task (Experiment 4). In Experiment 3, the pattern occurred only in the collective (not in the coactive) condition, providing direct evidence for social loafing. Together, these results suggest that people use stereotypes to tune their motivation to optimize the ratio of their own individual effort to the team's expected output.  相似文献   
920.
In contrast to motivational accounts of the personal-group discrepancy, results from this article suggest that the discrepancy is explained by aggregating different sets of comparison outcomes for either personal or group ratings. Results from a longitudinal study with East German (the minority group) and West German (the majority group) samples confirm the personal-group discrepancy and support our approach. First, social comparisons influenced evaluations of economic situation at both group and personal levels. Second, ratings of group versus personal economic situation were based on different sets of comparisons. Third, the mean structure of both sets of comparison outcomes mirrored the personal-group discrepancy. Fourth, an interaction between personal-group discrepancy and group status supported the authors' suggestions-concerning the direction of the discrepancy.  相似文献   
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