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21.
An extensive body of research using concurrent-chains schedules of reinforcement has shown that choice for one of two differentially valued food-associated stimuli is dependent upon the overall temporal context in which those stimuli are embedded. The present experiments examined whether the concurrent chains procedure was useful for the study of behavior maintained by alcohol and alcohol-associated stimuli. In Experiment 1, rats responded on concurrent-chains schedules with equal variable-interval (VI) 10-s schedules in the initial links. Across conditions, fixed-interval schedules in the terminal links were varied to yield 1∶1, 9∶1, and 1∶9 ratios of alcohol delivery. Initial-link response rates reflected changes in terminal-link schedules, with greater relative responding in the rich terminal link. In Experiment 2, terminal-link schedules remained constant with a 9∶1 ratio of alcohol delivery rates while the length of two equal duration initial-link schedules was varied. Preference for the rich terminal link was less extreme when initial links were longer (i.e., the initial-link effect), as has been previously reported with food reinforcers. This result suggests that the conditioned reinforcing value of an alcohol-associated stimulus depends on the temporal context in which it is embedded. The concurrent-chains procedure and quantitative models of concurrent chains performance may provide a useful framework within which to study how contextual variables modulate preference for drug-associated conditioned reinforcers. 相似文献
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Twelve-step programs such as Alcoholics Anonymous and Narcotics Anonymous invite members to trust that what is said in meetings remains confidential. However, the New York Times, a prominent and influential newspaper, has breached that confidentiality, offering both a precedent and a rationale to other media including newspapers, cable news programs, internet news blogs, and so on. This prominent breach may influence not only other news media but also the trust that 12-step members have in their programs. 相似文献
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造成药物治疗风险的因素包括药物因素、病情因素、患者因素、用药因素及管理因素等。通过对药物进行严格监管,对医药从业人员加强培训和教育,对民众开展科普教学和用药指导,可以降低药物治疗的风险。风险事件主要表现为用药差错、药物不良反应或药物治疗无效。在药物治疗中,首先必须时刻警惕和及时发现风险;其次需要全面评估风险,还要对疾病风险和药物治疗风险进行比较。应尽可能避免药物治疗的风险,对于必须承受的风险,需采取相应措施,减少风险事件发生的概率和严重程度。如果存在较大风险,务必同时设计处理风险事件的预案,并与患者及其家属保持良好的交流和沟通。 相似文献
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Warren K. Bickel Liqa N. Athamneh 《Journal of the experimental analysis of behavior》2020,113(1):48-56
The Reinforcer Pathology theory proposes conditions under which drugs emerge as excessively preferred reinforcers compared to other available reinforcers among drug users. The theory highlights 2 key variables as important determinants of drug preference: (a) excessive preference for immediate rewards (high discounting of future rewards); and (b) excessive valuation for addictive reinforcers (e.g., drugs). Two iterations of the Reinforcer Pathology theory exist with the latest iteration (i.e., Reinforcer Pathology 2.0) specifying that the temporal window of reinforcer integration (measured by delay discounting) is a determinant of reinforcer value. The 2 iterations of the Reinforcer Pathology theory are described. A novel insight and understanding of abstinence and relapse from a Reinforcer Pathology perspective, limitations, and future directions are discussed. The Reinforcer Pathology theory continues the long-standing efforts to scientifically understand and better define novel concepts and methods to further translational research and improve treatment outcomes. Exploring the complementary relation between the Reinforcer Pathology perspective and other current approaches could have a valuable effect. 相似文献
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细菌耐药性是一个严重的医学问题,并由于数量增加的耐药菌对多种结构无关的药物产生耐药而又无新的抗生素可使用而加剧。反义寡核苷酸可特异性抑制或下调同源基因表达,从而能成为基因治疗的首选药物。多年的研究表明:反义寡核苷酸能够有效抑制细菌代谢的基础酶类及致病基因;但也存在着一些尚未完全解决的问题。建议以科学哲学的方法论和系统方法为指导,展开多学科联合的科学活动,推动新型抗菌药的研发,使基因治疗早日实现。 相似文献
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植物药复方是中医辨证施治的主要手段。药物是通过蛋白质起作用的。蛋白质复杂多样的功能与其时空的复杂演变密切相关,复方如何对蛋白质时空产生影响、如何对其结构与功能发生作用以及两者之间相互作用、相互影响的深入研究可能发现新的生命现象,为阐明疾病发病机理以及植物药的创新研制奠定理论基础和提供技术支持。 相似文献
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This study examined (a) adolescent psychosocial risk factors for frequency (intensity) of marijuana use and for other illicit drug use among those who started using these drugs in early adulthood (adult initiators) and (b) the protective role of parent-adolescent relations in reducing or preventing drug use when adolescents enter early adulthood. The study's participants were male and female youth from a longitudinal prospective study. The participants' mean ages were 17 and 22 years at late adolescence and early adulthood, respectively. Independent measures assessed personality, parental, peer, and self-drug-use factors during late adolescence; dependent measures assessed frequency of marijuana use and other illicit drug use during early adulthood for initiators of the respective drug categories. The authors found that intensity of marijuana use was directly associated with the personality, parental, and self-drug-use domains and indirectly associated with the peer domain. Intensity of other illicit drug use was directly associated with personality and self-drug use. Analyses also revealed that some parent-adolescent relations factors buffered the effects of risk factors for both marijuana and other illicit drug-use intensity, whereas others enhanced the effects of protective factors against other illicit drug-use intensity. The results indicate that there are both commonalities and differences in precursors of marijuana and other illicit drug-use intensity among initiators of these drugs during early adulthood. 相似文献