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51.
喜树碱类药物四十年研发的回顾与反思   总被引:1,自引:0,他引:1  
通过对喜树碱类药物研发过程的历史回顾,探讨其存在的哲学意义和对其它植物药研发的价值。  相似文献   
52.

酒曲初始应用为酿酒,后我国先民发现酒曲可以用于治疗疾病便将其纳入方剂之中,方剂中的酒曲又逐渐演化成专供药用的药用曲。药用曲在我国古代各个时期具有鲜明的特征,在曲类药物的溯源研究中具有导向性作用。至1956年,《中药成药配制经验介绍》正式提出“曲剂”的名词概念和相关标准,药用曲的完整内涵得以呈现。随着传统中医与西方现代医学的交流与融合,药用曲的工艺科学价值、医药文化价值和学术启示价值得以重塑,其当代价值和实用意义进一步被明确。药用曲的发展历史折射出了我国酒曲药用的深厚认知观念和文化内涵。

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53.
本文从有关研究证据的基础上,介绍了个人化设计的理论基础和实验设计,并在此基础上讨论了个人化设计在临床研究领域中的应用价值,总结出一种适合临床病人使用的研究程序。个人化设计允许对个体的个人价值进行分析,并能同时研究不同刺激信息的作用,在个体水平上分析个体差异。通过简化了的实验程序,个人化设计为解决临床研究中的问题提供了一种新的思维方式。文中还对相关研究法的局限进行了讨论。  相似文献   
54.
The present study examined the relations between personal values, value congruence, interpersonal relationships and subjective well‐being in psychology/education and business students from Argentina (N = 275), Bulgaria (N = 182) and Finland (N = 148). Regression analyses showed, first, that there were no direct relations between higher order value priorities and life satisfaction (LS), positive affect (PA) or negative affect (NA). Second, objective value‐congruence (VC)—the similarity between individual and group values—was positively related to LS and PA, and negatively related to NA. Most importantly, the effects of VC on LS, NA and PA were partially mediated by good interpersonal relationships. Our results show that interpersonal relationships are facilitated by sharing values similar to those of one's fellow students. More generally, personal values per se appear not to be associated with subjective well‐being, more important is how these values fit into the social context. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
55.
Following a pretest, 8 participants who were unfamiliar with algebraic and trigonometric functions received a brief presentation on the rectangular coordinate system. Next, they participated in a computer-interactive matching-to-sample procedure that trained formula-to-formula and formula-to-graph relations. Then, they were exposed to 40 novel formula-to-graph tests and 10 novel graph-to-formula tests. Seven of the 8 participants showed substantial improvement in identifying formula-to-graph relations; however, in the test of novel graph-to-formula relations, participants tended to select equations in their factored form. Next, we manipulated contextual cues in the form of rules regarding mathematical preferences. First, we informed participants that standard forms of equations were preferred over factored forms. In a subsequent test of 10 additional novel graph-to-formula relations, participants shifted their selections to favor equations in their standard form. This preference reversed during 10 more tests when financial reward was made contingent on correct identification of formulas in factored form. Formula preferences and transformation of novel mathematical and stimulus functions are discussed.  相似文献   
56.
Choice between sucrose and wheel-running reinforcement was assessed in two experiments. In the first experiment, ten male Wistar rats were exposed to concurrent VI 30 s VI 30 s schedules of wheel-running and sucrose reinforcement. Sucrose concentration varied across concentrations of 2.5, 7.5, and 12.5%. As concentration increased, more behavior was allocated to sucrose and more reinforcements were obtained from that alternative. Allocation of behavior to wheel running decreased, but obtained wheel-running reinforcement did not change. Overall, the results suggested that food-deprived rats were sensitive to qualitative changes in food supply (sucrose concentration) while continuing to defend a level of physical activity (wheel running). In the second study, 15 female Long Evans rats were exposed to concurrent variable ratio schedules of sucrose and wheel-running, wheel-running and wheel-running, and sucrose and sucrose reinforcement. For each pair of reinforcers, substitutability was assessed by the effect of income-compensated price changes on consumption of the two reinforcers. Results showed that, as expected, sucrose substituted for sucrose and wheel running substituted for wheel running. Wheel running, however, did not substitute for sucrose; but sucrose partially substituted for wheel running. We address the implications of the interrelationships of sucrose and wheel running for an understanding of activity anorexia.  相似文献   
57.
Pigeons responded on concurrent-chains schedules with equal variable-interval schedules as initial links. One terminal link delivered a single reinforcer after a fixed delay, and the other terminal link delivered either three or five reinforcers, each preceded by a fixed delay. Some conditions included a postreinforcer delay after the single reinforcer to equate the total durations of the two terminal links, but other conditions did not include such a postreinforcer delay. With short initial links, preference for the single-reinforcer alternative decreased when a postreinforcer delay was present, but with long initial links, the postreinforcer delays had no significant effect on preference. In conditions with a postreinforcer delay, preference for the single-reinforcer alternative frequently switched from above 50% to below 50% as the initial links were lengthened. This pattern of results was consistent with delay-reduction theory (Squires & Fantino, 1971), but not with the contextual-choice model (Grace, 1994) or the hyperbolic value-added model (Mazur, 2001) as they have usually been applied. However, the hyperbolic value-added model could account for the results if its calculations were expanded to include reinforcers delivered in later terminal links. The implications of these findings for models of concurrent-chains performance are discussed.  相似文献   
58.
Abstract: The perceptual model of emotions maintains that emotions involve, or are at least analogous to, perceptions of value. On this account, emotions purport to tell us about the evaluative realm, in much the same way that sensory perceptions inform us about the sensible world. An important development of this position, prominent in recent work by Peter Goldie amongst others, concerns the essential role that virtuous habits of attention play in enabling us to gain perceptual and evaluative knowledge. I think that there are good reasons to be sceptical about this picture of virtue. In this essay I set out these reasons, and explain the consequences this scepticism has for our understanding of the relation between virtue, emotion, and attention. In particular, I argue that our primary capacity for recognizing value is in fact a non-emotional capacity.  相似文献   
59.
This study examined how four domain-specific skills (arithmetic procedural skills, number fact retrieval, place value concept, and number sense) and two domain-general processing skills (working memory and processing speed) may account for Chinese children’s mathematics learning difficulties. Children with mathematics difficulties (MD) of two age groups (7-8 and 9-11 years) were compared with age-matched typically achieving children. For both age groups, children with MD performed significantly worse than their age-matched controls on all of the domain-specific and domain-general measures. Further analyses revealed that the MD children with literacy difficulties (MD/RD group) performed the worst on all of the measures, whereas the MD-only group was significantly outperformed by the controls on the four domain-specific measures and verbal working memory. Stepwise discriminant analyses showed that both number fact retrieval and place value concept were significant factors differentiating the MD and non-MD children. To conclude, deficits in domain-specific skills, especially those of number fact retrieval and place value understanding, characterize the profile of Chinese children with MD.  相似文献   
60.
Negotiators often concede to angry partners. But what happens when they meet again? According to the spillover hypothesis, negotiators demand less from previously angry partners because they perceive them as tough. According to the retaliation hypothesis, negotiators demand more from previously angry partners because of negative impressions and a desire to get even. Experiment 1 showed that participants demanded less in later negotiations when their partner in a previous negotiation had expressed anger (rather than no emotion) and the later negotiation was with the same (rather than a different) partner. Consistent with the spillover hypothesis, this effect was mediated by inferences regarding the partner’s toughness. Experiment 2 showed that apologies reduce the negative effects of anger on impressions and desire for future interaction. Behavioral reactions were moderated by social value orientation: extending the established might/morality effect, prosocial participants responded cooperatively to an apology, whereas proselfs responded competitively.  相似文献   
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