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61.
药物的安全性是药物评价的首要标准。《欧盟传统药品法案》对中药的技术壁垒和我国对某些中药的毒副作用的披露,使得中药的安全性问题日益突出,使得中药产业面临前所未有的危机。对中药安全性的理性认识是扩大其国内市场占有率、走向国际市场所必须突破的瓶颈,也是中药产业危机管理的必由通道。这是一场深刻的文化革命。  相似文献   
62.
The relation between worrying and individuals' concerns was examined in a sample of 197 college students. Participants described the five undesirable outcomes that they thought about most often, indicated how likely they thought the outcomes were, and how upset they would be by them. Worry severity was measured using the Penn State Worry Questionnaire. The relation between worry severity and the life domains about which individuals were concerned was quite weak. In contrast, as predicted, greater worry was associated with higher probability and cost estimates. In addition, cost estimates moderated the relation between worry severity and probability estimates. The potential importance of perceived threat for understanding worrying is discussed.  相似文献   
63.
Perceived teasing experiences in body dysmorphic disorder   总被引:1,自引:0,他引:1  
Individuals with body dysmorphic disorder (BDD) are excessively concerned about imagined or slight defects in their appearance (e.g., asymmetrical facial features). Cognitive-behavioral models of BDD propose that several factors, including dysfunctional appearance-related beliefs and life experiences, such as teasing, contribute to the avoidance behaviors or rituals (e.g., mirror checking, grooming) characteristic of BDD. Previous research has demonstrated an association between perceived teasing and body dissatisfaction. In the current study, we examined whether individuals with BDD (n = 16) report to have been teased more often than do mentally healthy controls (n = 17). The group comprising individuals with BDD reported more appearance- and competency-related teasing than did control participants. This study provides preliminary evidence for the association between perceived teasing and BDD.  相似文献   
64.
The present study considered the relation between adolescent gambling behavior and the perceived environment, the component of Jessor and Jessor’s (1977) Problem Behavior Theory that assesses the ways that adolescents perceive the attitudes and behaviors of parents and peers. The predominantly African-American sample included 188 sophomores from two urban public high schools. Using the South Oaks Gambling Screen-Revised for Adolescents to assess gambling risk, rates of both at-risk (20.7%) and problem (12.8%) gambling were found to be high. Boys displayed more gambling problems than did girls. The perceived environment accounted for significant variance in gambling problems and frequency, with proximal components displaying stronger relationships than distal components. Perceiving parent gambling and friend models for problem behavior were positively correlated with gambling problems, and friend models were positively related to gambling frequency. Among girls, family support was positively related to gambling problems. Among boys, this relation was negative. The authors Emerson M. Wickwire, Jr. James P. Whelan, and Andrew W. Meyers are members of The Institute for Gambling Education and Research, Department of Psychology, The University of Memphis, Memphis, TN. The primary research interest of this group is the prevention and treatment of gambling related problems. David M. Murray, Ph.D., is the Chair of the Division of Epidemiology at the School of Public Health, The Ohio State University, Columbus, OH.  相似文献   
65.
The research on Tourette’s disorder (TD), a neuropsychological disorder consisting of motor and phonic tics, has largely focused on individuals with TD and not on the caregivers of children with TD. We investigated the effects of several variables on caregiver strain of caregivers of children with TD, including perceived social support, caregiver characteristics, and characteristics of the child’s disorder. An online survey was completed by 140 caregivers of children with TD between the ages of 6 to 18 years. We performed a path analysis to examine the outcome of caregiver strain in relation to the research variables. Our results indicated that caregiver age, symptom severity of the child’s TD, and perceived social support accounted for variance in caregiver strain, and that perceived social support was a partial mediator of child’s symptom severity and caregiver strain. Symptom severity and caregiver strain were also related to the presence of other comorbid disorders, such as Oppositional Defiant Disorder (ODD), anxiety, or Attention Deficit Hyperactivity Disorder (ADHD) when compared to children either having no other comorbid disorders or other types of disorders.  相似文献   
66.
We examined whether increasing individuals' perceived variability of an out-group reduces prejudice and discrimination toward its members. In a series of 4 laboratory and field experiments, we attracted participants' attention to either the homogeneity or the heterogeneity of members of an out-group, and then measured their attitudes or behaviors. Perceived variability was manipulated by making subgroups salient, by portraying the out-group members as having diverse opinions, by making salient that out-group members have different characteristics, or by asking participants to think about differences among out-group members. Prejudice and discrimination were measured in terms of self-reported attitudes, distribution of rewards, helping an out-group confederate, and evaluation of an out-group candidate in a simulated hiring decision. In all experiments, perceived variability decreased prejudice and discrimination. This effect may be due to the fact that perceived variability decreases the role of group membership in the production of attitudes and behaviors toward other individuals.  相似文献   
67.
Presently, the collection and analysis of naturalistic data is the most credited method for understanding road user behavior and improving traffic safety. Such methodology was developed for motorized vehicles, such as cars and trucks, and is still largely applied to those vehicles. However, a reasonable question is whether bicycle safety can also benefit from the naturalistic methodology, once collection and analyses are properly ported from motorized vehicles to bicycles. This paper answers this question by showing that instrumented bicycles can also collect analogous naturalistic data. In addition, this paper shows how naturalistic cycling data from 16 bicyclists can be used to estimate risk while cycling. The results show that cycling near an intersection increased the risk of experiencing a critical event by four times, and by twelve times when the intersection presented some form of visual occlusion (e.g., buildings and hedges). Poor maintenance of the road increased the risk tenfold. Furthermore, the risk of experiencing a critical event was twice as large when at least one pedestrian or another bicyclist crossed the bicyclist’s trajectory. Finally, this study suggests the two most common scenarios for bicycle accidents, which result from different situations and thus require different countermeasures. The findings presented in this paper show that bicycle safety can benefit from the naturalistic methodology, which provides data able to guide development and evaluation of (intelligent) countermeasures to increase cycling safety.  相似文献   
68.
ObjectivesSocial Cognitive Theory (SCT) has often been used as a guide to predict and modify physical activity (PA) behavior. We assessed the ability of commonly investigated SCT variables and perceived school environment variables to predict PA among elementary students. We also examined differences in influences between Hispanic and non-Hispanic students.DesignThis analysis used baseline data collected from eight schools who participated in a four-year study of a combined school-day curriculum and environmental intervention.MethodsData were collected from 393 students. A 3-step linear regression was used to measure associations between PA level, SCT variables (self-efficacy, social support, enjoyment), and perceived environment variables (schoolyard structures, condition, equipment/supervision). Logistic regression assessed associations between variables and whether students met PA recommendations.ResultsSchool and sex explained 6% of the moderate-to-vigorous PA models' variation. SCT variables explained an additional 15% of the models' variation, with much of the model's predictive ability coming from self-efficacy and social support. Sex was more strongly associated with PA level among Hispanic students, while self-efficacy was more strongly associated among non-Hispanic students. Perceived environment variables contributed little to the models.ConclusionsOur findings add to the literature on the influences of PA among elementary-aged students. The differences seen in the influence of sex and self-efficacy among non-Hispanic and Hispanic students suggests these are areas where PA interventions could be tailored to improve efficacy. Additional research is needed to understand if different measures of perceived environment or perceptions at different ages may better predict PA.  相似文献   
69.
To encourage appropriate use of driving automation, we need to understand and monitor driver’s trust and risk perception. We examined (1) how trust and perceived risk are affected by automation, driving conditions and experience and (2) how well perceived risk can be inferred from behaviour and physiology at three levels: over traffic conditions, aggregated risk events, and individual risk events.30 users with and without automation experience drove a Toyota Corolla with driving support. Safety attitude, subjective ratings, behaviour and physiology were examined.Driving support encouraged a positive safety attitude and active driver involvement. It reduced latent hazards while maintaining saliently perceived risks. Drivers frequently overruled lane centring (3.1 times/minute) and kept their feet on or above the pedals using ACC (65.8% of time). They comfortably used support on curvy motorways and monotonic and congested highways but less in unstable traffic and on roundabouts. They trusted the automation 65.4%, perceived 36.0% risk, acknowledged the need to monitor and would not engage in more secondary tasks than during manual driving.Trust-in situation reduced 2.0% when using automation. It was 8.2% higher than trust-in-automation, presumably due to driver self-confidence. Driving conditions or conflicts between driver and automation did not affect trust-in-automation.At the traffic condition level, physiology showed weak and partially counter-intuitive effects. For aggregated risk events, skin conductance had the clearest response but was discernible from baseline in  < 50%. Pupil dilation and heart rate only increased with strong braking and active lane departure assist. For individual risk events, a CNN classifier could not identify risk events from physiology. We conclude that GSR, heart rate and pupil dilation respond to perceived risk, but lack specificity to monitor it on individual events.  相似文献   
70.
National focus on individual freedom versus paternalistic values is a fundamental theme, which defines the status of traffic safety in different countries. The present study examines the role of such values in road safety culture based on survey data from car and bus drivers from three countries with distinctly different road safety records: Norway (N = 596), Israel (N = 129) and Greece (N = 386). While Norway has the highest road safety level in Europe, and Israel also performs better than the EU average, the road safety level in Greece was far below the EU average. As these positions reflect differences in policies and national regulations in drivers’ freedom to take risk, we hypothesize a higher focus on individual freedom to take risk and lower focus on paternalism among the Greek drivers. Results indicate, in accordance with our hypothesis, that the Greek drivers value freedom to take risk in traffic higher than drivers from Norway and Israel. Greek drivers also expect higher levels of risk taking from other drivers in their country, they report higher levels of risky driving themselves, and are more often involved in accidents. Thus, it seems that values have an important role in Road Safety Culture (RSC), legitimizing and motivating risky driving, which are related to accidents. We found, however, contrary to our hypotheses, that the Greek drivers also had the most paternalistic attitudes among the drivers in the three countries. In the present paper, we try to solve this Greek paradox.  相似文献   
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