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1.
The Theory of Rational Addictions, by Gary Becker & Kevin Murphy (1988), was a rational choice model that became a standard tool for economists modeling addictive behavior. The approach differs from other theories of addiction by modeling addictive behavior as the gradual implementation of a rational, forward‐looking plan, where consumption at any point in time is partly motivated by the immediate payoff of consumption and partly by the effects this consumption has on the individual in the future. This makes addictive behavior a subset of rational behavior, requiring no more specific government policies or attention than any other consumption choice. Later work by economists extended the theory in different ways, allowing it to match an increasing number of consumption patterns, and searched for ways to test the forward‐looking assumption in different types of market data. While the work was successful as a contribution to rational choice theory, with possible statistical applications, there are several reasons to dismiss its usefulness as an explanation of real‐world addictive behavior and its ability to assess the welfare effects of addictions.  相似文献   
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Some researchers speculate that as many as 10% of users worldwide suffer from “problematic” use of the internet, possibly stemming from an internet dependency. Research is in its early stages, making it an uncertain issue for mental health professionals. This paper provides: (1) a critical review of research on problematic internet use for the mental health and addictions professional; and (2) practical implications, including suggestions on treatment and prevention, given its uncertain clinical classification.  相似文献   
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Over the last two decades there has been accumulating evidence that both psychosocial and pharmacological treatment interventions can effect change in substance-misusing adults. Thus, treatment interventions implemented for young people with substance problems largely draw on the adult addiction experience and that of child and adolescent psychiatry and psychology. As young people with problematic drug use have different treatment needs, and require different interventions and services to those of adults, results of adult studies cannot necessarily be directly extrapolated to young people.

Over the last five years evidence has been rapidly mounting that treatment may potentially work in young people, but as yet it is not as extensive as that for adults. The interventions that appear most fruitful are those based on learning theory, e.g. cognitive behavioural therapy and family therapy. Outcome studies in young people demonstrate substantial variability in substance use and misuse following treatment. From the UK perspective, the evidence is almost entirely USA based, and these evaluations of non-UK treatment programmes for young people cannot be simply transferred or transported to UK healthcare settings. This has significant implications for practice and policy.

At this stage, 'guidelines' or 'guidance' that is available is either not directed at young people and/or is largely gleaned from the USA literature. In addition, it does not adequately capture the complexity of cases at front-line specialist settings. The management of young substance misusers in the UK is, in the main, 'beyond guidelines and guidance'.

The restricted treatment service network for young people in the UK makes the potential for undertaking studies on treatment effectiveness extremely limited, but because there is evidence of a growing number of young people requiring treatment, such specialist drug services require evaluation. Serious consideration of the establishment and funding of evaluation of treatment interventions to be delivered to young substance misusers in the UK is urgently needed.  相似文献   
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The effect of prenatal exposure to nicotine on nicotine-induced analgesia was studied in rats. The analgesic effect of a single dose of nicotine (1 mg/kg SC) was measured by the tail-flick technique, and two subsequent studies were carried out. In the first study, 7-month-old male rats, born to dams chronically treated with nicotine during pregnancy (NIC), exhibited prolonged nicotine-induced analgesia compared to matched controls. The second study was designed to explore whether rats prenatally exposed to nicotine (NIC rats) are born with an increased sensitivity to nicotine and whether there is any sex difference. The analgesic effect of nicotine was tested on control and NIC rats of both sexes once a month from 2 to 7 months of age. At an early age, male but not female NIC rats, exhibited shorter analgesic responses to nicotine than did the matched controls. With increasing age, however, the duration of nicotine analgesia began to be prolonged in NIC rats of both sexes. Significant differences between control and NIC rats were found at the age of 6 and 7 months, in both sexes. Thus, rats prenatally exposed to nicotine are not born with an increased sensitivity to the analgesic effect of a single dose of nicotine. This phenomenon develops later, during the course of life, independently of gender.  相似文献   
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Smoking and raven IQ   总被引:1,自引:0,他引:1  
Nicotine has recently been shown to enhance measures of information processing speed including the decision time (DT) component of simple and choice reaction time and the string length measure of evoked potential waveform complexity. Both (DT and string length) have been previously demonstrated to correlate with performance on standard intelligence tests (IQ). We therefore hypothesised that nicotine is acting to improve intellectual performance on the elementary information processing correlates of IQ. In the current experiment we tested this hypothesis using the Raven Advanced Progressive Matrices (APM) test. APM scores were significantly higher in the smoking session compared to the non-smoking session, suggesting that nicotine acts to enhance physiological processes underlying performance on intellectual tasks.  相似文献   
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文章针对目前医学生“网络成瘾症”的现状进行了分析,并指出了产生的原因和解决问题的办法,以求达到标本兼治。最后提出三点预防医学生“网络成瘾症”的对策:一是高校及其附属医院要为医学生营造宽松愉快的学习、生活环境;二是呼吁家长关注医学生身心发展的特殊规律,建立良好的家庭环境;三是建立和完善与网络社会相应的法律法规,规范医学生的网上行为。  相似文献   
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