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51.
The systematic development of early age talent in sports academies has led to the professionalization of pediatric sport and the sports physician need to be aware of pediatric cardiological problems. Research into the medical cardiac care and assessment of the pediatric athlete are accumulating, but specific pediatric international guidelines are not available yet and reference data for ECG and echocardiography are incomplete, in particular for the age group <12 years of age. This article is an introduction to the physiological and diagnostics specifics of the pediatric athlete. The focus lies in the differences in presentation and diagnosis between pediatric and adult athletes for the most common pathologies. Reference data for electrical and structural adaptations to intensive exercise are sparse particularly in athletes aged below 12 years old. Training related changes include decrease of resting heart rate, increase of cardiac output, ventricular cavity size, and wall thickness. Cardiac hypertrophy is less pronounced in pediatric athletes, as HR mediated cardiac output increase to endurance exercise is the dominant mechanism in peripubertal children. As in adults, the most pronounced cardiovascular adaptations appear in classical endurance sports like rowing, triathlon, and swimming, but the specifics of pediatric ECG and echocardiographic changes need to be considered.  相似文献   
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Relapse is associated with a poor prognosis among drug users. Crack cocaine users are more prone to severe dependence because of the intensity of use. Additionally, initiating drug use during adolescence worsens users' prognosis due to the increased rates of impulsivity and other risk behaviors. This study aimed to identify the predictors of early relapse among adolescent crack users discharged from inpatient treatment. A cohort study was conducted with 89 psychiatric inpatients aged 12–17 years from two different hospitals in southern Brazil who met the criteria for crack abuse or dependence. Demographic data, substance use disorders, psychiatric comorbidities, and crack consumption profile were assessed during hospitalization using the Teen Addiction Severity Index, Schedule for Affective Disorders and Schizophrenia for School Age Children—Present and Lifetime, and Crack Consumption Profile. Participants were re-assessed at 1 and 3 months after hospital discharge to determine their crack cocaine use based on self-report, family/caregiver information, and urine tests, whenever possible. There were extremely high rates of relapse (valid percent) in the first and third months, 65.9 and 86.4%, respectively. Statistically significant associations were observed between relapse in the first month and length of cocaine/crack cocaine use, and length of hospital stay. Data at 3 months were not analyzed because of the small number of patients who did not relapse. The high rates and significant associations found in this study suggest that intensive outpatient treatment strategies targeting this population should be developed and implemented to prevent early relapse after detoxification. One of the possible approaches, based on recent studies, might explore motivation as a strategy to reduce the rate of early relapse.  相似文献   
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《Substance use & misuse》2013,48(3):221-233
Guided by rigorous methodology and a life-course perspective, the goal of this research is to address a gap in current knowledge on whether, when, and how strongly intergenerational continuity of substance use exists when examining age-equivalent and developmentally specific stages of the life course. Annual self-reported substance use measures were analyzed from a prospective, longitudinal, and nationally representative sample that originally consisted of 1,725 respondents and their families, who were then interviewed over a 27-year period from 1977 to 2004. Findings from multilevel random-intercept regression models provide support for intergenerational continuity when substance use occurs in emerging adulthood but not when limited to adolescence. Implications, limitations, and future research directions are discussed.  相似文献   
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Background: To help immigrant and refugee adolescents experiencing a severe academic delay cope with adversity, a school‐based intervention combining drama workshops and language awareness activities was piloted in two classrooms. Method: A qualitative analysis of participant observations was performed and the Strength and Difficulty Questionnaire and its Impairment Supplement was administered before and after the intervention. The observations were carried out in two Montreal high schools serving an underprivileged neighbourhood of immigrants, involving two classrooms of underschooled adolescents (n = 27) and two classes of similarly underschooled adolescents chosen among other teachers interested in the intervention, who accepted to participate as a comparison group (n = 28). Results: The adolescents shared their experiences of adversity and felt empowered by the workshops. Self‐reported impairment decreased in the intervention groups. Conclusion: The protective effect of creative language activities for immigrant and refugee youth should be further investigated.  相似文献   
56.
In this article, I attempt to illuminate points of similarity between the process of “working through” in psychological treatment, and the ordinary day-to-day developmental potential of college life, suggesting that when students can be helped to make optimal use of the college interpersonal milieu, brief, analytically informed psychotherapy can work in concert with the average, expectable experimentation of late adolescence to facilitate growth and maturation.  相似文献   
57.

Background:

Binge drinking is prevalent during adolescence and may have effects on the adult brain and behavior. The present study investigated whether adolescent intermittent ethanol exposure alters adult risky choice and prefrontal dopaminergic and forebrain cholinergic neuronal marker levels in male Wistar rats.

Methods:

Adolescent (postnatal day 28–53) rats were administered 5g/kg of 25% (vol/vol) ethanol 3 times/d in a 2-days–on/2-days–off exposure pattern. In adulthood, risky choice was assessed in the probability discounting task with descending and ascending series of large reward probabilities and after acute ethanol challenge. Immunohistochemical analyses assessed tyrosine hydroxylase, a marker of dopamine and norepinephrine in the prelimbic and infralimbic cortices, and choline acetyltransferase, a marker of cholinergic neurons, in the basal forebrain.

Results:

All of the rats preferred the large reward when it was delivered with high probability. When the large reward became unlikely, control rats preferred the smaller, safe reward, whereas adolescent intermittent ethanol-exposed rats continued to prefer the risky alternative. Acute ethanol had no effect on risky choice in either group of rats. Tyrosine hydroxylase (prelimbic cortex only) and choline acetyltransferase immunoreactivity levels were decreased in adolescent intermittent ethanol-exposed rats compared with controls. Risky choice was negatively correlated with choline acetyltransferase, implicating decreased forebrain cholinergic activity in risky choice.

Conclusions:

The decreases in tyrosine hydroxylase and choline acetyltransferase immunoreactivity suggest that adolescent intermittent ethanol exposure has enduring neural effects that may lead to altered adult behaviors, such as increased risky decision making. In humans, increased risky decision making could lead to maladaptive, potentially harmful consequences.  相似文献   
58.
The objective of this study was to assess the degree of concordance between two popular classification systems [the Centers for Disease Control and Prevention (CDC)‐2000 and the Institute of Medicine (IOM)‐2009] used to categorise the nutritional status of pregnant adolescents. This cross‐sectional study involved 327 pregnant adolescents (10–19 years) booking for antenatal care at a single public maternity in São Paulo, Brazil. Participants were classified into one of four categories, by both systems according to their pre‐pregnancy body mass index and age. The CDC‐2000 system classified significantly fewer pregnant adolescents as underweight (3.7% vs. 12.5%, P < 0.0001) and significantly more adolescents as normal‐weight (86.8% vs. 75.6%, P = 0.0003) than the IOM‐2009 system. The distribution of the adolescents in the two systems differed significantly. The global rate of discordance was 13.5%. The overall concordance between the two systems was marginally good (K = 0.63), being moderate for younger (<16 years) adolescents (K = 0.52). Approximately one in every seven pregnant adolescent would be classified in a non‐corresponding category if the IOM‐2009 classification was used instead of the CDC‐2000 classification. The IOM‐2009 nutritional classification, which does not take into account age and gender, tends to overestimate the proportion of underweight adolescents, especially in the younger‐age group. The use of this classification system can lead to recommendations of higher gestational weight gain in a substantial proportion of pregnant adolescents, which could predispose to post‐partum weight retention and future obesity.  相似文献   
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