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81.
The effects of income (money available to spend during the experimental session) on human choice were examined in a concurrent-schedule arrangement. Subjects were 7 nicotine-dependent smokers, and reinforcers were puffs on the subject's usual brand of cigarette ("own") and puffs on a less preferred brand of cigarette with equal nicotine content ("other"). Across sessions, income varied and the price of the two reinforcers was held constant, with the other puffs one fifth the price of the own puffs. As income increased, consumption of own puffs increased while consumption of the less expensive other puffs decreased. These effects of income on choice were highly consistent across subjects. For some subjects, however, income had little effect on total puff consumption. Finally, an additional condition examined whether price and income manipulations would have functionally equivalent effects on choice by repeating an income condition in which the price of the other brand was increased. Although the increased price of the other puffs decreased their consumption in 4 subjects, 2 subjects showed increased consumption of the other puffs at the higher price. The results, when defined in economic terms, indicate that the own puffs were a normal good (consumption and income are directly related), the other puffs were an inferior good (consumption and income are inversely related), and the direct relationship between consumption of the other puffs and their price is defined as a Giffengood effect. The latter result also suggests that for these 2 subjects, price and income manipulations had equivalent effects on choice. These results extend findings from previous studies that have examined the effects of income on choice responding to human subjects and drug reinforcers, and provide a framework for further experimental tests of the effects of income on human choice behavior. Methodological and theoretical implications for the study of choice and for behavioral pharmacology are discussed.  相似文献   
82.
The purpose of the first experiment was to investigate whether diazepam could acquire anxiogenic properties by signalling an aversive event. Rats were trained in an operant chamber in the pentylenetetrazol (PTZ) model of anxiety. Thereafter the animals were divided into groups that received classical diazepam conditioning (Group 1), and conditioning of diazepam + tone (Group 2). In the test phase diazepam was injected prior to placement in the operant chamber. Group 2 selected the PTZ-appropriate lever more often than the other groups, indicating that the tone induced anxiety, and diazepam did not. Tones and shock may therefore be more easily associated than diazepam and shock. The second experiment investigated this. Rats were trained the same way as in the first experiment. Thereafter the experimental group received injections of a small dose of diazepam prior to a second injection of a large dose of diazepam. The hypothesis was that a compensatory anxiogenic conditional response to diazepam's anxiolytic effect should be elicited by the small dose. There were no differences between the groups in lever selection, indicating that a compensatory anxiogenic response was not elicited.  相似文献   
83.
242例吸毒女性自尊及背景资料的调查与分析   总被引:1,自引:0,他引:1  
运用自尊量表和背景资料调查问卷对甘肃省两大戒毒所242例吸毒女性进行测查,结果表明:(1)年龄、婚姻状况、文化程度、经济收入水平等因素与吸毒女性自尊评分无显著相关;(2)回归分析显示,人际关系因子对吸毒女性自尊评分有显著影响,认知、行为因子对其自尊评分的影响没有达到显著性水平;(3)文化程度不高,无固定的经济收入,失恋或离婚等因素是吸毒或吸毒成瘾的重要关联因素。  相似文献   
84.
克服肿瘤干细胞耐药性的策略和思路   总被引:1,自引:1,他引:0  
肿瘤干细胞(cancersterncells,CSCs)是肿瘤细胞的祖细胞。已有的研究表明,肿瘤干细胞对多种化疗药物具有耐药性,是导致肿瘤治疗后复发的根源。研究针对肿瘤干细胞的治疗方法,克服肿瘤干细胞耐药性,将给肿瘤治疗模式带来全新的改变,有望彻底改善肿瘤患者的预后。  相似文献   
85.
This study investigated the lived experience of substance abusers in the South African context. Participants were 10 individuals attending a drug treatment centre in Durban, South Africa. Data were collected using open-ended interviews with data being analysed using thematic analysis. Findings suggest that normative social influences and levels of social support play an important role in shaping, maintaining, and determining the trajectory of drug usage.  相似文献   
86.
通过对本地一所三级甲等医院进行的围手术期抗菌药物的干预对照研究,用SPSS软件对470个手术病例的调查资料进行了统计分析,加强抗菌药物的用药管理及进行用药干预,能在对住院时间和手术切口感染率无影响的同时,明显降低手术病例的药品费用,特别是抗茵药品的费用,减轻患者负担。  相似文献   
87.
科学证据不仅在司法审判中起着极其重要的作用,而且在科研成果的评价中也是不可取代的,但是在审判和科研成果评估中,对“科学是什么”这样一个更深层次的问题-科学哲学问题,历来没有得到应有的重视,通过美国止吐药本涤汀前后历时20年的审判历程,突出科学哲学在医药审判实践中的地位。  相似文献   
88.
Grunbaum claims that the remedial failure of atreatment's characteristic factors is thegeneric, objective property of a placebo. Hestipulates that a treatment is placebic if thisremedial failure exacerbates the targetdisorder. This stipulation can subsume asplacebic effects that might be solelypharmacological, e.g., paradoxical reactions tocertain psychiatric drugs. If that exacerbationcan be explained pharmacologically, then wemight question whether Grunbaum's definitionalscheme captures the core identity of what weusually intend by the placebo concept. Ipropose that this core identity is bestcaptured by a symbolic meaning hypothesis inwhich psychological factors exert thedeterminative influence.  相似文献   
89.
The development of drug discrimination was assessed in rhesus monkeys using the conditioned taste-aversion paradigm. Monkeys were initially trained to respond under a fixed-ratio 30-response schedule of food-pellet delivery to assess the rate-decreasing effects of alprazolam (0.03 to 3 mg/kg, i.m., 60 min presession). Alprazolam decreased responding at doses greater than 0.1 mg/kg. Discriminative stimulus effects of alprazolam were then assessed by giving 0.03 mg/kg before sessions in which 1.8 mEq/kg lithium chloride was given immediately after the session (alprazolam/lithium session). On intervening days, saline was given before and after the session (saline/saline session). Rates of responding decreased over successive alprazolam/lithium sessions and also during the saline/saline session that immediately followed an alprazolam/lithium session. During subsequent saline/saline sessions, rates of responding returned to levels near baseline rates within two to four sessions. The discriminative stimulus effects of alprazolam were then assessed by giving 0.1 mg/kg before sessions in which 1 mg/kg d-amphetamine was given immediately after the session (alprazolam/d-amphetamine session). Rates of responding decreased during subsequent alprazolam/d-amphetamine sessions in drug-experienced monkeys, but did not decrease during intervening saline/saline sessions. These findings demonstrate that drug stimuli associated with postsession drug injections can rapidly develop control over behavior and suggest that similar methods be explored in the assessment of drug discrimination.  相似文献   
90.
Response-contingent deliveries of oral pentobarbital maintained responding of 3 rhesus monkeys during daily 3-hr sessions. Deliveries of pentobarbital were arranged under nonindependent concurrent variable-ratio variable-ratio schedules. Responses to either schedule counted toward completion of both variable-ratio schedule requirements. This schedule is similar in some respects to conventional concurrent variable-interval variable-interval schedules, in which passage of time counts toward completion of the interval value on both schedules. Restricted nonindependent concurrent variable-ratio variable-ratio schedules were also studied. On that schedule, when a drug delivery was assigned to one spout, it had to be collected before responses on the opposite spout again counted toward completion of the schedule requirements. Relative reinforcer magnitude was varied by changing the drug concentration on one schedule while keeping the drug concentration constant on the other variable-ratio schedule. Under both types of concurrent variable-ratio schedules, the relative rate of responding corresponded to the relative drug intake. Unlike earlier studies of concurrent variable-interval variable-interval intravenous cocaine reinforcement, preference was proportionate to concentration, and exclusive preferences did not develop. The relationship between relative rate of responding and relative drug intake was well described by the generalized matching law.  相似文献   
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