首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   449篇
  免费   83篇
  国内免费   51篇
  583篇
  2024年   3篇
  2023年   24篇
  2022年   15篇
  2021年   16篇
  2020年   33篇
  2019年   32篇
  2018年   28篇
  2017年   38篇
  2016年   43篇
  2015年   25篇
  2014年   23篇
  2013年   65篇
  2012年   11篇
  2011年   17篇
  2010年   14篇
  2009年   22篇
  2008年   32篇
  2007年   31篇
  2006年   14篇
  2005年   16篇
  2004年   13篇
  2003年   8篇
  2002年   14篇
  2001年   8篇
  2000年   3篇
  1999年   3篇
  1998年   1篇
  1997年   5篇
  1996年   1篇
  1994年   4篇
  1993年   2篇
  1992年   1篇
  1991年   1篇
  1990年   2篇
  1989年   1篇
  1988年   1篇
  1987年   1篇
  1986年   1篇
  1984年   2篇
  1982年   1篇
  1979年   4篇
  1978年   1篇
  1976年   2篇
  1975年   1篇
排序方式: 共有583条查询结果,搜索用时 0 毫秒
511.
把无效的治疗误认为有效,不仅在大众中非常普遍,而且很多医生也常如此。造成这种疗效假象有许多原因,主要由于疾病的自愈或自发缓解、药物和治疗的安慰效应、缺乏严格的评价疗效标准以及诊断不确实,以及把良性疾病误诊为严重或恶性疾病所造成的。对传统医疗的信仰也是原因之一。因此,对任何药物或医疗的效果必须进行严格的随机对照临床试验,并且得到同行的检验和公认。  相似文献   
512.
OBJECTIVE: To compare the frequency of nail biting in 4 settings (interventions) designed to elicit the functions of nail biting and to compare the results with a self-report questionnaire about the functions of nail biting. DESIGN: Randomised allocation of participants to order of conditions. SETTING: University Psychology Department. SUBJECTS: Forty undergraduates who reported biting their nails. INTERVENTIONS: Left alone (boredom), solving maths problems (frustration), reprimanded for nail biting (contingent attention), continuous conversation (noncontingent attention). MAIN OUTCOME MEASURES: Number of times the undergraduates bit their nails. RESULTS: Nail biting occurred most often in two conditions, boredom and frustration. CONCLUSION: Nail biting in young adults occurs as a result of boredom or working on difficult problems, which may reflect a particular emotional state. It occurs least often when people are engaged in social interaction or when they are reprimanded for the behavior.  相似文献   
513.
The financial implications of the increased prevalence of autism, though rarely discussed, will be extremely important to society. We compared the costs associated with 18 years of special education to the costs associated with the implementation of an average of 3 years of Discrete Trial Training as an Early Intensive Behavioral Intervention (EIBI) in an effort to minimize the need for special education. Our results indicate that the state of Texas would save $208,500 per child across eighteen years of education with EIBI. When applied to the conservative estimate of 10,000 children with autism in Texas, the State would save a total of $2.09 billion with EIBI. Implications for taxpayers, policymakers, and treatment are discussed.  相似文献   
514.
本研究运用结构性观察方法对两组4岁儿童与父母在四种活动中的互动进行了分析与比较。一组儿童为书面数符号测查高分者,二组儿童为书面数符号测查低分者。85对父母一儿童对子参加了4个各有15分钟的共同活动,阅读、数学题、纸和积木,并完成一个微型问卷。结果表明,在这些活动中包含了多种数学知识学习和多种以父母为主导的互动策略;两组对子之间在数学事件频次上无差异,但一组父母更多地运用了一些积极策略,二组父母更多地运用了一些消极策略;二组中有更多儿童对互动表现出消极回应和注意力问题。两个组的父母在家中与儿童一起进行诸如阅读和做数学题的共同活动的频次与质量上表现出差异。  相似文献   
515.
The number of responses rats made in a "run" of consecutive left-lever presses, prior to a trial-ending right-lever press, was differentiated using a targeted percentile procedure. Under the nondifferential baseline, reinforcement was provided with a probability of .33 at the end of a trial, irrespective of the run on that trial. Most of the 30 subjects made short runs under these conditions, with the mean for the group around three. A targeted percentile schedule was next used to differentiate run length around the target value of 12. The current run was reinforced if it was nearer the target than 67% of those runs in the last 24 trials that were on the same side of the target as the current run. Programming reinforcement in this way held overall reinforcement probability per trial constant at .33 while providing reinforcement differentially with respect to runs more closely approximating the target of 12. The mean run for the group under this procedure increased to approximately 10. Runs approaching the target length were acquired even though differentiated responding produced the same probability of reinforcement per trial, decreased the probability of reinforcement per response, did not increase overall reinforcement rate, and generally substantially reduced it (i.e., in only a few instances did response rate increase sufficiently to compensate for the increase in the number of responses per trial). Models of behavior predicated solely on molar reinforcement contingencies all predict that runs should remain short throughout this experiment, because such runs promote both the most frequent reinforcement and the greatest reinforcement per press. To the contrary, 29 of 30 subjects emitted runs in the vicinity of the target, driving down reinforcement rate while greatly increasing the number of presses per pellet. These results illustrate the powerful effects of local reinforcement contingencies in changing behavior, and in doing so underscore a need for more dynamic quantitative formulations of operant behavior to supplement or supplant the currently prevalent static ones.  相似文献   
516.
选取杭州市122名学前儿童(3~6岁)为被试,以点数比较任务及点数异同任务测量幼儿的近似数量系统敏锐度,以数数测验、基数测验、符号数字知识测验及简单计算来测量幼儿的符号数学能力,以此考察学前儿童近似数量系统敏锐度的发展及与符号数学能力的关系。结果发现:(1)随年龄增长,学前儿童的近似数量加工的敏锐度逐渐提高;(2)点数比较任务与点数异同任务均适合测量学前儿童近似数量系统敏锐度,但儿童完成点数比较任务的正确率要高于点数异同任务的正确率;(3)在抑制控制、短时记忆、工作记忆和言语测验成绩被控制后,根据点数比较任务计算的韦伯系数能显著预测学前儿童的基数和符号数字知识测验分数,总正确率能显著预测学前儿童的数数、基数、符号数字知识测验分数;(4)点数异同任务中只有点数不同试次下的正确率能显著预测学前儿童的符号数字知识测验分数。  相似文献   
517.
近年来,为推进精准医学创新药物的发展,美国食品药品监督管理局推出了“篮子试验”和“雨伞试验”;开始批准依照生物标志物而不是肿瘤来源区分的抗肿瘤药物和适应症;并开始在药物临床评价中引用“真实世界证据”。显然,现代医学摒弃了以基于疾病分类的“随机对照试验”为金标准的理念,开始建构适应个性化医学的临床评价体系。中医辨证论治具备了个性化医学的全部特征,完全适用于这个临床评价体系。基于科学规范对辨证体系的标准化,将大数据技术用于临床的“真实世界”,并根据个性化原则进行疗效评价,将形成适合中医学的科学而经济的临床评价体系。  相似文献   
518.
The Helsinki Declaration is the ‘gold standard’ — a directive, not a law, on how to conduct controlled studies in humans in conformity with ethical principles. In spite of many discussions about their unsuitability some articles have remained unchanged in the most recent (sixth) revision of the Declaration. The demand to use “the best treatment” excludes use of placebo in the control group and presents an obstacle to the scientific evaluation of a number of drugs and treatments in general. The use of placebo is justified whenever its use does not cause irreversible damage or considerable suffering to the well informed patient. It must be, is, and will be used in the controlled clinical trials of treatments of a great number of diseases especially those which have a tendency to spontaneous improvement, even healing, or have a pronounced psychological component An earlier version of this paper was presented at an international conference, “Placebo: Its Action and Place in Health Research Today,” held in Warsaw, Poland on 12–13 April, 2003.  相似文献   
519.
"感"·"象"·"数"--《周易》经传象数观念的哲学人类学释读   总被引:1,自引:0,他引:1  
王浩 《周易研究》2005,(3):10-18
象数观念是<周易>经传乃至易学中的基础和核心观念.历来对象数观念的理解和解释,往往局限于象数观念本身,而对<周易>经传的产生背景、以及其中的另一个重要观念--"感",则关注不够.本文从哲学人类学的视角,在考察<周易>经传的产生背景以及"感"、"象"、"数"三者之间关系的基础上,认为<周易>经传中的象数观念其实是原始时代的感性具体的思维方式及其宇宙观的积淀.具体说来,"数"也是"象",它们本来都是"互渗"或"交感"的中介;换句话说,<周易>经传象数观念的最终依据其实是感;象数因感而蕴涵着向天道观和伦理观发挥的可能性.  相似文献   
520.
It is assumed that number magnitude comparison is performed by assessing magnitude representation on a single analog mental number line. However, we have observed a unit-decade-compatibility effect in German which is inconsistent with this assumption (Nuerk, Weger, & Willmes, 2001). Incompatible magnitude comparisons in which decade and unit comparisons lead to different responses (e.g., 37_52 for which 3<5, but 7>2) are slower and less accurately responded to than compatible trials in which decade and unit comparisons lead to the same response (e.g., 42_57, for which 4<5 and 2<7). As overall distance was held constant, a single holistic magnitude representation could not account for this compatibility effect. However, because of the inversion property of the corresponding German two-digit number words ("einundzwanzig" ), the language-generality of the effect is questionable. We have therefore examined the compatibility effect with native English speakers. We were able to replicate the compatibility effect using Arabic notation. Thus, the compatibility effect is not language-specific. However, in cross-linguistic analyses language-specific modulations were observed not only for number words but also for Arabic numbers. The constraints imposed on current models by the verbal mediation of Arabic number comparison are discussed.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号