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111.
    
This study considers a navigation method for finding the most preferable radiotherapy plan from a discrete set using planner‐defined clinical criteria. The method is based on repeatedly solving an optimization model to identify a plan that best satisfies the aspiration values set by the planner. During navigation, the planner iteratively adjusts the aspiration values to match the preference information learned from previous plans until the most preferable plan is identified. The use of soft constraints to model aspiration values enables navigation amongst a discrete set and allows the planner to freely specify the aspiration values without producing an infeasible model. We demonstrate the use of the model by applying it to a prostate cancer case. This illustrates that improvements in optimization criteria do not necessarily lead to improvements in clinical criteria. Hence, the method obviates the need to simultaneously monitor both optimization and clinical criteria in current navigation systems. Instead, the direct use of clinical criteria for navigation aids the planner to quickly identify the most preferable plan.  相似文献   
112.
Three pigeons were trained on a matching procedure involving a sample component and a choice component. Responding in the sample component, according to either a differential-reinforcement-of-low-rate schedule on some trials or a differential-reinforcement-of-other-behavior schedule on other trials, produced access to the choice component in which each of two keys was illuminated with a unique color. The correct choice response was defined by the contingency that was met to produce the choice. The food hopper operated for 1.5 seconds following an appropriate sample response and for 3 seconds following a correct choice response. A signal-detection analysis showed that variations in the probability of presentation of the different contingencies systematically affected response bias but not sensitivity to the contingencies as stimuli. Substitution of a blackout for food at the end of the sample component did not differentially affect performance, but elimination of the delay between sample and choice components generally increased the sensitivity measure. The findings suggest a role for reinforcement contingency discrimination in schedule-controlled responding.  相似文献   
113.
Rats discriminated auditory intensity differences of sinusoids at 3.0 kilohertz in a go/no-go signal detection procedure. Responses to the signal (hits) were reinforced with electrical brain stimulation, and misses produced a brief timeout. On intermixed noise trials, withholding of responses (correct rejections) was reinforced, and false alarms produced the time-out. In two test conditions, the signal was either the louder (100 decibels) or softer (90, 93, 96, or 99 decibels) of the pair of intensities presented within a set of trials. Each animal was first trained with signal value louder or softer, and reversed for the second condition so that the former noise value served as signal. Hits showed shorter latencies than false alarms, regardless of the relative intensity of signal and noise, and the magnitude of differentiation was proportional to signal-noise separation. Both hits and false alarms showed longer latencies as the discrimination became more difficult. Isosensitivity contours derived from the latencies showed close similarity across conditions; in comparison, the yes-no measure of detectability, d', showed greater variability. The similarity of latency differentiation across louder and softer signal conditions supports a detection model in which the observer's judgment is controlled by the distance of sensory effect from criterion on each trial, as opposed to the loudness of the tones per se.  相似文献   
114.
While premature infants have a high need for positive interactions, both infants and their mothers are challenged by the infant‘s biological immaturity. This randomized clinical trial of 198 premature infants born at 29–34 weeks gestation and their mothers examined the impact of the H-HOPE (Hospital to Home: Optimizing the Infant's Environment) intervention on mother–premature infant interaction patterns at 6-weeks corrected age (CA). Mothers had at least 2 social environmental risk factors such as minority status or less than high school education. Mother–infant dyads were randomly assigned to the H-HOPE intervention group or an attention control group. H-HOPE is an integrated intervention that included (1) twice-daily infant stimulation using the ATVV (auditory, tactile, visual, and vestibular-rocking stimulation) and (2) four maternal participatory guidance sessions plus two telephone calls by a nurse-community advocate team. Mother–infant interaction was assessed at 6-weeks CA using the Nursing Child Assessment Satellite Training–Feeding Scale (NCAST, 76 items) and the Dyadic Mutuality Code (DMC, 6-item contingency scale during a 5-min play session). NCAST and DMC scores for the Control and H-HOPE groups were compared using t-tests, chi-square tests and multivariable analysis. Compared with the Control group (n = 76), the H-HOPE group (n = 66) had higher overall NCAST scores and higher maternal Social-Emotional Growth Fostering Subscale scores. The H-HOPE group also had significantly higher scores for the overall infant subscale and the Infant Clarity of Cues Subscale (p < 0.05). H-HOPE dyads were also more likely to have high responsiveness during play as measured by the DMC (67.6% versus 58.1% of controls). After adjustment for significant maternal and infant characteristics, H-HOPE dyads had marginally higher scores during feeding on overall mother–infant interaction (β = 2.03, p = 0.06) and significantly higher scores on the infant subscale (β = 0.75, p = 0.05) when compared to controls. In the adjusted analysis, H-HOPE dyads had increased odds of high versus low mutual responsiveness during play (OR = 2.37, 95% CI = 0.97, 5.80). Intervening with both mother and infant is a promising approach to help premature infants achieve the social interaction patterns essential for optimal development.  相似文献   
115.
Abstract

Behavioral Marital Therapy has focussed on the modification of marital behavior in conjoint and couples group settings. This study extends previously published outcome studies in that one treatment condition involved treating only one of the partners. Fifty-seven couples were consecutively assigned to one of the three treatment conditions. Outcome evaluations included an independent assessment, marital satisfaction, sexual adjustment and an assessment of target problems. The results revealed no significant differences between the three treatment conditions. However, couples in the conjoint treatment resolved their target problems more rapidly than the other two treatments. The implications of the result as well as issues of outcome prediction, cost-effectiveness and the viability of treating one spouse are discussed.  相似文献   
116.
饮食行为包含个体对饮食的风味感知、口感评价、情绪感受、个人饮食偏好以及外显的进饮动作等一系列心理与行为过程。研究相继表明:声音主要通过影响人们对饮食的感官感受性与喜好程度来影响饮食行为。饮食行为中的声音信息包括内感受性线索(Interoceptive cues),即个体与饮食的交互音(如咀嚼食物声、吞咽饮品声,制作与准备饮食过程中的声音等);外感受性线索(exteroceptive cues),即环境音(主要指噪音)与背景音乐。行为研究结果普遍强调认知因素在声音与饮食间所起的作用,如注意的分散与转移、跨通道联结(匹配性效应)、期望与回避(潜在的音画效应)等。而神经科学则以"听-嗅-味"为突破口,从"多通道整合"的角度为理论间的争议寻求更为清晰的证据与潜在的内部机制;与此同时,情绪唤醒、躯体标示(内隐联结)与具身认知视角有望成为新的理论整合点。  相似文献   
117.
Sixth-grade students were exposed to two pairs of mathematics assignments. Assignment Pair A included a high-effort and a moderate-effort assignment, each containing 18 three-digit by two-digit (3×2) problems. Assignment Pair B was similar except the high-effort assignment contained six additional one-digit by one-digit (1×1) problems interspersed following every third 3×2 problem. After exposure to each pair of assignments, students ranked assignments and chose a new assignment for homework. Analysis of Assignment Pair A data showed students preferred the moderate-effort assignment. Analysis of interactions showed that interspersing the additional brief problems to the high-effort assignment caused significantly more students to choose the high-effort assignment for homework and rank it as requiring less effort and time to complete and as being less difficult than the moderate-effort assignment. Results support the hypothesis that a discrete task is a reinforcer and suggest that educators can increase the probability of students engaging in more challenging assignments that require more effort to complete by interspersing additional brief tasks. Applied and theoretical implications are discussed along with future research.  相似文献   
118.
在2003年诺贝尔医学奖获奖名单公布以后,未曾获奖的MRI人士达马迪安,自恃对MRI技术医用方面作出过杰出贡献,而未中选.遂与友人-起在三张美国大报和一张瑞典大报,刊登广告,声称不公平待遇.但医学奖诺贝尔委员会发言人认为,在大量未获奖人士中,这种做法极为罕见;这一现象对诺贝尔奖评选有参考价值,即使时科学界也有多重启示.至于诺贝尔基金会拟改革,估计未必触动"三人规则".  相似文献   
119.
三种常用DIF检测方法的比较研究   总被引:5,自引:1,他引:5  
本研究在对DIF作出新的更为严格的界定、对三种常用的DIF检澍方法进行详细介绍的基础上.以1999年高考英语试卷75道选择题为研究材料,对三种常用的DIF检测方法进行了实证研究。结果表明:MH方法与SIBTEST方法检测的敏感性较STND方法高;MH方法与SIBTEST方法检出的一致性很高;SIBTEST方法具有较好的性能,在实际应用中可以作为首选的方法;在进行DIF检测时,样本容量在1000左右为宜。  相似文献   
120.
心理实验设计的程序化思路   总被引:5,自引:0,他引:5  
袁登华  王重鸣 《心理科学》2002,25(3):300-302
本研究讨论了在心理实验过程中选择各种设计类型的关键条件,并以流程图的形式将各种设计类型串起来,理出了一条心理实验设计的程序化思路。  相似文献   
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