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951.
The relationships between specific quantities and frequencies of alcohol, cigarette, and illicit substance use and substance use (SUD) and other psychiatric disorders were investigated among 1,285 randomly selected children and adolescents, aged 9 to 18, and their parents, from the Methods for the Epidemiology of Child and Adolescent Mental Disorders (MECA) Study. Logistic regressions indicated that daily cigarette smoking, weekly alcohol consumption, and any illicit substance use in the past year were each independently associated with an elevated likelihood of diagnosis with SUD and other psychiatric disorders (anxiety, mood, or disruptive behavior disorders), controlling for sociodemographic characteristics (age, gender, ethnicity, family income). The associations between the use of specific substances and specific psychiatric disorders varied as a function of gender.  相似文献   
952.
953.
Three experiments were conducted to examine the theoretical prediction that the intensity of sadness is determined not only by the instigating event but also by factors that impede or deter the function or purpose of sadness. In the first two experiments, participants were asked to read a story designed to induce sadness, and were then given a $1, $2, or $3 gift. In both, reported sadness was higher for persons receiving a $2 gift than for those receiving either a $1 or $3 gift. However, the increase in sadness from the $1 to $2 group failed to reach an acceptable level of significance. In the second experiment, as expected, a $1 gift produced less sadness than did the story by itself, and as in the first experiment, a $2 gift resulted in more sadness than either a $1 or $3 gift. The third experiment replicated the $1 and $2 conditions and obtained a highly reliable effect; sadness was greater among those who received the $2 gift. Measures of positive affect suggested that participants experienced either sadness or positive feelings, not both.  相似文献   
954.
We assessed the immediate effects of two universal, first-grade preventive interventions on the proximal targets of poor achievement, concentration problems, aggression, and shy behaviors, known early risk behaviors for later substance use/abuse, affective disorder, and conduct disorder. The classroom-centered (CC) intervention was designed to reduce these early risk behaviors by enhancing teachers' behavior management and instructional skills, whereas the family-school partnership (FSP) intervention was aimed at improving parent-teacher communication and parental teaching and child behavior management strategies. Over the course of first and second grades, the CC intervention yielded the greatest degree of impact on its proximal targets, whereas the FSP's impact was somewhat less. The effects were influenced by gender and by preintervention levels of risk. Analyses of implementation measures demonstrated that greater fidelity to the intervention protocols was associated with greater impact on behavior ratings and on achievement scores, thus providing some evidence of specificity in the effect of the interventions.  相似文献   
955.
There is no question that the motor control system will adapt under fatiguing conditions; however, there is documented evidence showing that when fatigued or challenged, the motor control system will, on occasion, perform inappropriate muscle sequencing, increasing the risk of injury, or directly causing injury. Knowing that inappropriate muscle activations can lead to injury, the purpose of this study was to investigate motor patterns during cognitive and physical challenges. Rather than ensure change with severe challenges, milder challenges were purposefully chosen. Eight male subjects performed a low external load task performed near end ROM while in an unchallenged state, and while in three challenged states: passive tissue creep, muscle fatigue and cognitive distraction. Data were collected using EMG of the trunk muscles and angular displacement of the lumbar spine. Comparison of motor control patterns between the unchallenged state and each of the three challenged conditions showed no systematic differences. However, several random anomalies were observed. A case study of a single subject was chosen to show inappropriate motor control during one trial under the cognitive distraction conditions. The response of the motor control system is very individualized and does on occasion produce inappropriate motor patterns. This supports the notion that injury may also occur as the result of random motor control errors as well as predictable, systematic changes.  相似文献   
956.
The purpose of this study was to investigate the effects of gender and gender-role stereotypes on judgments of help-giving. As part of a 2 × 2 within-subjects design, 40 undergraduates read 4 different scenarios that described either a man or a woman needing help in either a stereotypically masculine or a stereotypically feminine situation. Although male participants felt more sympathy for men in stereotypically feminine situations and for women in stereotypically masculine situations, they were no more likely to help these individuals than they were to help those in gender-consistent situations. By contrast, women were more likely to help people in gender-inconsistent situations, despite feeling the most sympathy for people needing help in masculine situations. Implications for Weiner's (1980) attribution model of help-giving and Nadler & Fisher's (1986) threat-to-self-esteem model are discussed.  相似文献   
957.
Differential reinforcement of other behavior (DRO) and differential reinforcement of low rates of responding (DRL) have been effective techniques in reducing maladaptive behaviors in therapeutic settings. Reported studies of these reinforcement-based procedures indicate that they are usually implemented in isolation, targeting only a single behavior or class of behaviors. In this study, multiple DRO and DRL contingencies were utilized concurrently in reducing two distinct classes of behaviors with a 26 year-old blind man with moderate retardation. One class of behaviors included socially inappropriate verbalizations, while the other included aggressive, self-injurious and environmentally destructive behaviors. Distinct contingencies were established according to the functions of the targeted behaviors and their severity and separate schedules of reinforcement were derived from baseline frequencies. Over a period of 20 months, the differential reinforcement interventions resulted in rapid reduction of behaviors in both classes to near-zero rates and frequencies were maintained at this low level while contingency schedules were systematically lengthened. Collateral effects are discussed including performance in functional academics and participation in community integration activities.  相似文献   
958.
Two males diagnosed with cocaine dependence received a behavioral intervention comprised of contingency management and the community reinforcement approach. During the initial phase of treatment, reinforcement was delivered contingent on submitting cocaine-free urine specimens. The community reinforcement approach involved two behavior therapy sessions each week. Almost complete cocaine abstinence was achieved, but regular marijuana use continued. During a second phase, reinforcement magnitude was reduced, but remained contingent on submitting cocaine-free specimens. Behavior therapy was reduced to once per week. Cocaine abstinence and regular marijuana use continued. Next, reinforcement was delivered contingent on submitting cocaine- and marijuana-free specimens. This modified contingency resulted in an abrupt increase in marijuana abstinence and maintenance of cocaine abstinence. One- and 5-month follow-ups indicated that cocaine abstinence continued, but marijuana smoking resumed. These results indicate that the behavioral intervention was efficacious in achieving abstinence from cocaine and marijuana; maintenance, however, was achieved for cocaine only.  相似文献   
959.
Describes a conceptual framework for identifying and targeting developmental antecedents in early childhood that have been shown in previous work to predict delinquency and violent behavior, heavy drug use, depression, and other psychiatric symptoms and possibly disorders in late adolescence and into adulthood. Criteria are described that guided choices of targets for two epidemiologically based, randomized preventive trials carried out in 19 elementary schools in the eastern half of Baltimore, involving more than 2,400 first-grade children over the course of first and second grades. Baseline models derived from the first of two cohorts show the evolving patterns of concurrence among the target antecedents. The central role of concentration problems emerged. From Fall to Spring in first grade, concentration problems led to shy and aggressive behavior and poor achievement in both genders and to depressive symptoms among girls. There was evidence for reciprocal relationships in girls. For example, depressive symptoms led to poor achievement in both girls and boys, whereas poor achievement led to depressive symptoms in girls but not boys, at least over the first-grade year. These results provide important epidemiological data relevant to the developmental paths leading to the problem outcomes and suggest preventive trials.  相似文献   
960.
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