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21.
In the current investigation, we compared two methods of food presentation (simultaneous vs. sequential) to increase consumption of nonpreferred food for 3 children with food selectivity. In the simultaneous condition, preferred foods were presented at the same time as nonpreferred food (e.g., a piece of broccoli was presented on a chip). In the sequential condition, acceptance of the nonpreferred food resulted in presentation of the preferred food. Increases in consumption occurred immediately during the simultaneous condition for 2 of the 3 participants. For 1 participant, increases in consumption occurred in the simultaneous condition relative to the sequential condition, but only after physical guidance and re-presentation were added to treatment. Finally, consumption increased for 1 participant in the sequential condition, but only after several sessions. These results are discussed in terms of possible mechanisms that may alter preferences for food (i.e., establishing operations, flavor-flavor conditioning).  相似文献   
22.
当代中国的社会转型   总被引:9,自引:0,他引:9  
本文以我国社会生活发生的广泛而深刻的变化为背景,深入揭示了这种变化深层的社会转型。这种转型就是:由权力社会走向能力社会;由人治社会走向法治社会;由人情社会走向理性社会;由依附社会走向自立社会;由身份社会走向实力社会;由注重先天给定社会走向注重后天努力社会;由一元化社会走向多样化社会;由人的依赖社会走向物的依赖社会;由静态社会走向流动社会;由“国家”社会走向“市民”社会。  相似文献   
23.
This study introduces the Amsterdam Chess Test (ACT). The ACT measures chess playing proficiency through 5 tasks: a choose-a-move task (comprising two parallel tests), a motivation questionnaire, a predict-a-move task, a verbal knowledge questionnaire, and a recall task. The validity of these tasks was established using external criteria based on the Elo chess rating system. Results from a representative sample of active chess players showed that the ACT is a very reliable test for chess expertise and that ACT has high predictive validity. Several hypotheses about the relationships between chess expertise, chess knowledge, motivation, and memory were tested. Incorporating response latencies in test scores is shown to lead to an increase in criterion validity, particularly for easy items.  相似文献   
24.
Present optimization techniques in latent class analysis apply the expectation maximization algorithm or the Newton-Raphson algorithm for optimizing the parameter values of a prespecified model. These techniques can be used to find maximum likelihood estimates of the parameters, given the specified structure of the model, which is defined by the number of classes and, possibly, fixation and equality constraints. The model structure is usually chosen on theoretical grounds. A large variety of structurally different latent class models can be compared using goodness-of-fit indices of the chi-square family, Akaike’s information criterion, the Bayesian information criterion, and various other statistics. However, finding the optimal structure for a given goodness-of-fit index often requires a lengthy search in which all kinds of model structures are tested. Moreover, solutions may depend on the choice of initial values for the parameters. This article presents a new method by which one can simultaneously infer the model structure from the data and optimize the parameter values. The method consists of a genetic algorithm in which any goodness-of-fit index can be used as a fitness criterion. In a number of test cases in which data sets from the literature were used, it is shown that this method provides models that fit equally well as or better than the models suggested in the original articles.  相似文献   
25.
What response times tell of children's behavior on the balance scale task   总被引:4,自引:0,他引:4  
Analysis of accuracy of responses to balance scale problems gives a global idea of the cognitive processes that underlie problem-solving behavior on this task. We show that response times (RTs) provide additional detailed information about the kind and duration of these processes. We derive predictions about the RTs from Siegler's (1981) model for the balance scale task, including the counterintuitive prediction that young adults are slower than children in solving particular balance scale problems. The predictions were tested in a study in which 191 6- to 22-year-old participants were presented with a computerized balance scale task. RTs were analyzed with regression models. In addition to qualitative differences between items, we also modeled quantitative differences between items in the regression models. Analyses supported the predictions and provided additional knowledge on the rules. Rule II was reformulated as a rule that always involves the encoding, but not always the correct application of the distance cue. RTs provided evidence for the use of a buggy-rule and not an addition-rule. Finally, a relation between rule inconsistency and increased RT was found.  相似文献   
26.
依据Rayleigh颜色匹配方法研制人眼颜色视觉定量测量实验装置,并对20名色觉正常和30名色觉异常大学生的颜色视觉进行测量。结果表明,色觉异常被试在Rayleigh匹配中点和匹配范围测量值上均与色觉正常被试者存在明显的差异。  相似文献   
27.
耳科学在人类与耳部疾病的斗争中兴起了19世纪,在本世纪随科学技术的发展而获得迅速发展,特别是抗菌素和手术显微镜的出现,使耳显同外科技术不断提高,不仅能彻底地祛除耳部感染,而且可以有效地提高听力,耳科学家在聋病的治疗过程中,已能够有效地治疗传导性耳聋,但仍面临着治疗神经性耳聋的挑战,在现代科学技术革命的推动下,随着分析子生物学,细胞生物学等新技术的发展,在21世纪,人类必定能够彻底治疗聋病。  相似文献   
28.
论中西医结合的过程与层次   总被引:2,自引:0,他引:2  
中西医结合是一个长期困扰人们的难题。中医理论研究人体外部现象的变化规律,以古代哲学思想为指导,具有整体联系、动态把握的合理内核。而目前现代医学对人体结构和功能的认识,并不能完全揭示生命现象本质,因而也不能完全解释中医现象。这种认识有一个不断发展和深化的过程,自然辩证法观点认为层次越低、结合越紧密。分子导次是具有生物意义的最低层次。人类“基因组”计划的实现可能在一个新的高度阐明人体本质,也使中医现象  相似文献   
29.
汉字词识别过程的形,音,义编码作用的研究   总被引:7,自引:0,他引:7  
本文通过两个实验,采用汉字词形、音、义特征匹配任务,探讨了影响汉字词的形、音、义编码与提取方式的有关因素。实验一发现在速示条件下,对汉字词再认的成绩并不受字词的使用度的影响,反应时无明显变化,而主要受编码加工的深度影响。在形、音、义特征加工中,对音码的加工时间最长,再认的正确率最低;义码的加工时间较短,再认正确率最高;形码的反应时及再认成绩介于音码与义码之间。实验二在非速示条件下也获得了相同的结果。研究结果表明,在汉字词的形、音、义特征中,存在着编码加工深度的差异。  相似文献   
30.
论马克思主义的整体性(上)   总被引:1,自引:0,他引:1  
近年来,随着 "马克思主义理论"被正式确立为国家一级学科,"马克思主义学院"在全国高等院校纷纷成立,国内马克思主义研究在表面上也呈现出一派热闹非凡的景象。于是马克思主义的整体性问题被提了出来。然而,与这种表面上热闹的景象形成鲜明对照的是,真正从心灵深处认同、信仰马克思主义的人并不很多。这种悖论式的现象不能不引起我们足够的重视。对于研究马克思主义的理论工作者而言,必须对眼前令人眼花缭乱的马克思主义 "热"进行 "冷"思考,就是说,必须认真地、郑重地提出并弄清这样一个问题: 马克思主义就其本义而言,是站在大众立场、为大众立言、为  相似文献   
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