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排序方式: 共有4413条查询结果,搜索用时 15 毫秒
1.
Ole Rogeberg 《Addiction (Abingdon, England)》2020,115(1):184-187
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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K. Miura S. Yamaoka K. Arizono S. Ohba T. Koga T. Kawasaki N. Yoshida I. Asahina 《The British journal of oral & maxillofacial surgery》2019,57(6):529-535
Our aim was to evaluate the long-term skeletal stability of the mandible in 21 patients after orthognathic surgery with physiological positioning. The measurement points SNB, B point (X, Y), Pog (X, Y), and the angle of the ramus were measured on cephalometric photographs to assess skeletal stability preoperatively, immediately after operation, and one and two years postoperatively. In addition, we evaluated the clinical symptoms of disorders of the temporomandibular joint (TMJ). The analysis of the cephalometric photographs showed that SNB, B point X, and Pog X showed no significant differences among the postoperative time points. On the other hand, B point Y and Pog Y showed no significant differences throughout the study period. We compared the angle of the ramus before operation and two years postoperatively, and no significant difference was found. In addition, no cases showed any pathological symptoms of disorders of the TMJ two years postoperatively. The long-term stability after orthognathic surgery with physiological positioning was confirmed, and it seems to be a reliable orthognathic treatment in patients with mandibular prognathism. 相似文献
5.
Rotary ventricular assist devices (VADs) are less sensitive to preload than the healthy heart, resulting in inadequate flow regulation in response to changes in patient cardiac demand. Starling‐like physiological controllers (SLCs) have been developed to automatically regulate VAD flow based on ventricular preload. An SLC consists of a cardiac response curve (CRC) which imposes a nonlinear relationship between VAD flow and ventricular preload, and a venous return line (VRL) which determines the return path of the controller. This study investigates the importance of a physiological VRL in SLC of dual rotary blood pumps for biventricular support. Two experiments were conducted on a physical mock circulation loop (MCL); the first compared an SLC with an angled physiological VRL (SLC‐P) against an SLC with a vertical VRL (SLC‐V). The second experiment quantified the benefit of a dynamic VRL, represented by a series of specific VRLs, which could adapt to different circulatory states including changes in pulmonary (PVR) and systemic (SVR) vascular resistance versus a fixed physiological VRL which was calculated at rest. In both sets of experiments, the transient controller responses were evaluated through reductions in preload caused by the removal of fluid from the MCL. The SLC‐P produced no overshoot or oscillations following step changes in preload, whereas SLC‐V produced 0.4 L/min (12.5%) overshoot for both left and right VADs. Additionally, the SLC‐V had increased settling time and reduced controller stability as evidenced by transient controller oscillations. The transient results comparing the specific and standard VRLs demonstrated that specific VRL rise times were improved by between 1.2 and 4.7 s ( = 3.05 s), while specific VRL settling times were improved by between 2.8 and 16.1 seconds ( = 8.38 s) over the standard VRL. This suggests only a minor improvement in controller response time from a dynamic VRL compared to the fixed VRL. These results indicate that the use of a fixed physiologically representative VRL is adequate over a wide variety of physiological conditions. 相似文献
6.
Jennifer B. Gray Neal D. Gray 《International journal of mental health and addiction》2006,4(4):307-318
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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Ilana B. Crome 《Drugs (Abingdon, England)》2006,13(3):203-224
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
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
9.
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
10.
D. R. JASINSKI 《Acta anaesthesiologica Scandinavica》1997,41(1):184-186
In the 19th century, investigators recognized that addiction to opiates involves tolerance and dependence. In the United States, the National Academy of Sciences and the Public Health Service initiated systematic investigations into opiate addiction in 1929. Tolerance and dependence to morphine, the prototype for opiate drugs, were the emphasis of human studies for the next fifty years. This presentation highlights salient features of tolerance and dependence learned in these studies and relates these findings to clinical use in treating pain. 相似文献