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BACKGROUND: The primary aim was to examine correlated growth trajectories and reciprocal effects between academic achievement and drug use over the course of junior high school. METHODS: One hundred and three male and 98 female students from 3 rural junior high schools were surveyed 4 times over the course of 3 years. Dual trajectory latent growth models were estimated. RESULTS: Growth trajectories of school achievement and drug use over the course of junior high were highly correlated. Students who demonstrated deteriorating achievement during the course of junior high school showed an increase in drug use during this same time frame. Cross-process regressions indicated that students who demonstrated superior academic achievement in sixth grade exhibited a shallower rate of increase in drug use (ie, their drug use escalated to a lesser extent). CONCLUSIONS: The processes of academic disengagement (as marked by deteriorating grades) and drug use during adolescence appear to be related to one another. Prevention initiatives aimed at keeping adolescents academically engaged in school may have protective benefits against escalation of drug use.  相似文献   
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Abstract

This study was designed to determine whether illness during the academic year, when gender and academic readiness are controlled, is the variable accounting for the demonstrated relationship between life change index and subsequent academic performance. A weak though significant inverse association was found between life change and grades: this association persisted even after statistical adjustment for gender, academic readiness, and illness experience. There was no evidence that illness experience mediated the life change-performance relationship. The association was not subject to a threshold effect according to level of life change.  相似文献   
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The dentistry course in Sri Lanka is conducted in English, a second language for its students. A decade ago, English language proficiency was the key factor in predicting the academic performance of first year dental undergraduates. Since then, changes have been introduced to the teaching programme and examination format to minimise the effect of language proficiency on their performance. This study aimed at re‐evaluating the factors influencing academic performance in a similar academic cohort. A total of 306 first year students in five consecutive academic years ranging in age from 20 to 24 years (77% of the total number registered, 36.3% men) were recruited, and a questionnaire was used to collect data regarding demographics, previous academic ability and perceived levels of difficulty of the first year course, English language and its sub‐skills. Performances of the English language test and cumulative GPA of the first year course were used as objective indicators of language competency and academic performance respectively. The data were analysed using SPSS 11.5. Hierarchical Regression Analysis revealed that English language proficiency, gender and previous academic ability were the significant predictors of GPA. Students who received a lower GPA perceived English as considerably more difficult compared to the academic course itself; however, students who obtained a higher GPA perceived the opposite. Students' language competency remains the major predictor of academic performance, although previous academic ability and gender emerge as significant predictors. The perceived difficulty, however, of the dental course and of studying in English may also be predictors of student academic performance.  相似文献   
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目的 回顾中国残疾研究的发展历程,归纳发展的规律、特点和不足,对未来学科的发展提出建议。方法 检索1986年至2018年CNKI中研究主题为“残疾”的文献,根据题目和摘要对文献进行筛选。运用描述性分析梳理我国残疾研究的发展情况,利用文献计量分析软件VOSviewer探究本领域研究者间的合作情况和研究热点。结果 共纳入有效文献2 267篇。我国残疾研究自1986年出现以来,在数据驱动下迅速发展,呈现出明显阶段性特征。目前已初步形成学术合作网络基础,呈现多主题综合发展的态势。但随着学科发展进入到新时期,研究基础条件后续支持力不足,以及研究理论创新和研究内容拓展缓慢等可能会成为阻碍学科发展的关键因素。结论 未来应夯实研究基础,包括拓宽合作交流渠道,加强残疾统计工作,促进学科交叉研究。加强理论研究,包括规范研究方法,结合国情寻找内化的理论创新点。丰富研究内容,尤其是紧密结合当前残疾人需求变化,加强残疾人口的残疾防控、健康促进、社会融合、社会管理方面的研究。  相似文献   
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Objectives: To determine the prevalence of impaired left ventricular (LV) systolic function and its impact on the in‐hospital and long‐term outcome in patients who underwent Transcatheter Aortic Valve Implantation (TAVI). Background: Although impaired LV function may be considered a contra‐indication for aortic valve replacement, the hemodynamic characteristics of transcatheter valves may offer procedural and long‐term clinical benefit in such patients. Methods: 230 consecutive patients underwent TAVI with the Medtronic‐CoreValve System. Impaired LV function was defined by a Left Ventricular Ejection Fraction (LVEF) ≤ 35% (European Multicenter Study on Operative Risk Stratification and Long‐term Outcome in patients with Low‐Flow/Low‐Gradient Aortic Stenosis). Study endpoints were selected and defined according to the Valve Academic Research Consortium recommendations. Results: Compared with patients with a LVEF > 35% (n = 197), those with LVEF ≤ 35% (n = 33) were more often male (78.8 % vs. 46.7%, P < 0.001), more symptomatic (NYHA class III or IV, 97.0% vs. 77.2%, P = 0.008) and had a higher prevalence of prior coronary artery disease (63.6% vs. 43.1%, P = 0.029). The Logistic EuroSCORE was 14.8% and 22.8, respectively (P = 0.012). No difference was observed between the two groups in in‐hospital or 30‐day mortality (3.0% vs. 9.6%, P = 0.21), the Combined Safety Endpoint at 30 days (24.2% and 24.4%, P = 0.99) and survival free from readmission at one year (69.2% and 69.7%, P = 0.85). After adjustment, LVEF ≤ 35% was not associated with an increased risk of 30‐day mortality, in‐hospital complications and survival free from readmission at follow‐up. Conclusion: The immediate and long‐term outcome after TAVI did not differ between patients with an impaired and preserved LVEF. LVEF ≤ 35% did not predict adverse immediate and long‐term outcome. These findings suggest that TAVI should not be withheld in selected patients with impaired LV function. © 2011 Wiley Periodicals, Inc.  相似文献   
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