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991.
The purpose of the present study was to examine the effect of the presence of a reliability observer on the number of positive parent behaviors recorded by a primary observer during naturalistic parent-child interactions. Thirty parents and their young clinic-referred children served as subjects. After two initial home observations, a reliability observer was present to record data in observation session 3, but not session 4, for one-half the subjects. For the remaining subjects the reliability observer was present in session 4 but not session 3. The results of a 2 × 2 analysis of variance indicated a group by session interaction which resulted from an increase in maternal attention to the child in the presence of a reliability observer. Hypotheses to explain the finding are presented and implications of the results are discussed.This research was supported in part by NIMH Grant MH28859-01.  相似文献   
992.
993.
In previous studies of human newborn sucking, the effects of increasing fluid sweetness and/or volume included a decrease in sucking rate within sucking bursts and, paradoxically, an increase in heart rate. To determine whether the heart rate increase can be attributed to increased sucking amplitude for sweeter fluids, sucking and heart rates of 20 full-term infants were studied. Half sucked for three consecutive 2-min periods, first receiving small drops of water for each suck, then no fluid, then 15% sucrose. The other half experienced the reverse order. The results for sucking and heart rate were consistent with previous studies; sucking rates within bursts were slowest for sucrose and fastest for no fluid. Heart rate was higher for sucrose than for the other fluid conditions, however, only in the water-first group. The heart rate increase was significant on statistical tests which controlled for sucking amplitude as well as for several other motor variables. Sucking amplitude itself varied with fluid sweetness in the water-first group only, in which it was highest for water. There were more total sucks, longer sucking bursts, and less time between successive bursts under the sucrose condition. Multivariate statistics helped establish a set of dependent variables—sucking rate within bursts, total number of sucks, and heart rate—which most parsimoniously describes the effects of fluid sweetness. A hedonic explanation of the response of newborns to sweetness is thus reiterated.  相似文献   
994.
Reversal and nonreversal shifts in nineteen 2- to 14-year-old autistic children were studied. Each child was taught both a reversal and nonreversal shift discrimination task. The reversal shift condition entailed teaching the child to respond to one (the S+) of a pair of stimuli during training and subsequently reversing the S+ during testing. The nonreversal shift condition consisted of teaching the child two unrelated discriminations during training and testing. The results indicated that the older autistic children did better on reversal shifts than younger children who did better on nonreversal shifts. These findings are consistent with those for normal children.  相似文献   
995.
Grain was briefly presented to food-deprived pigeons intermittently and response-independently except during signaled timeouts. During Experiment 1, key pecks postponed the next timeout for a specified interval. Rates of pecking during time in were inversely related to the length of time pecking postponed the next timeout. Response-independent presentation of temporal distributions of timeouts exactly matched to a preceding postponement condition decreased pecking rates during Experiment 2. These results indicate that key pecking of pigeons can be controlled by response-dependent postponement of timeout, but that responses elicited by stimulus-reinforcer relations inherent in timeout-postponement procedures may substantially modify rates and patterns of pecking.  相似文献   
996.
The aim of this paper is to describe a structured approach to managing the disengagement process. Six distinct disengagement scenarios are first outlined. Thereafter, phasing out therapy, dealing with family belief systems concerning the permanence of improvements and relapse management are discussed. Ways in which disengagement from specific episodes of therapy may be construed as part of an ongoing therapeutic relationship and the practicalities of recontracting for further episodes of therapy, handing over cases, and referring cases on to other professionals are considered. An approach to therapeutic failure analysis is presented. Finally, ways in which disengagement may lead to significant loss experiences are discussed.  相似文献   
997.
警惕啊!基因决定论   总被引:3,自引:0,他引:3  
基因已经成为20世纪遗传学中的一个关键词基因决定论也正在走近我们的生活本文从遗传学的角度阐述了基因决定论的种种不当之处,并且指出基因的作用与人类的生活方式密切相关,而人类的全部文明史就在于克服单纯的基因决定论所带来的局限。  相似文献   
998.
The perception of shape from shading was tested in two chimpanzees (Pan troglodytes) and five humans (Homo sapiens), using visual search tasks. Subjects were required to select and touch an odd item (target) from among uniform distractors. Humans found the target faster when shading was vertical than when it was horizontal, consistent with results of previous research. Both chimpanzees showed the opposite pattern: they found the target faster when shading was horizontal. The same difference in response was found in texture segregation tasks. This difference between the species could not be explained by head rotation or head shift parallel to the surface of the monitor. Furthermore, when the shaded shape was changed from a circle to a square, or the shading type was changed from gradual to stepwise, the difference in performance between vertical and horizontal shading disappeared in chimpanzees, but persisted in humans. These results suggest that chimpanzees process shading information in a different way from humans. Received: 20 January 1998 / Accepted after revision: 30 March 1998  相似文献   
999.
Qualitative methods were used to develop a contextually relevant quantitative measure of parenting stress and inform the design of family-focused interventions aimed at preventing adolescent mental and behavioral health problems. The study focused on the experiences of low-income one- and two-parent families representing three ethnic groups (Mexican, African, and European Americans) living in low-income neighborhoods in a large Southwestern city. This report describes the place of this study in a broader program of prevention research, the qualitative methods and data analysis procedures employed, and how the results were used to develop a new measure of parenting stress and inform future program design. The report also includes reflective comments on the methods used and lessons gained.  相似文献   
1000.
To what extent are models of memory general, in that they may be applied to children or to other cultural groups? In an attempt to answer this question, two experiments were undertaken in Morocco to investigate various cultural and experiential antecedents to memory development. A total of 384 children and young adults, ranging in age from 6 to 22 years, were tested in a design that contrasted schooled and nonschooled children in urban and rural environments. Three additional groups of subjects—Koranic students, Moroccan rug sellers, and University of Michigan students—were also studied because it was hypothesized that each might have particular “culture-specific” memory skills as a function of previous experience.A serial short-term recall task was used in Experiment I. Results showed that the recency effect or short-term store was generally invariant with age or experience. Control processes appeared to be a function of age, but only when coupled with schooling, and, to a lesser extent, urban environment. In Experiment II, a continuous recognition memory task was given with black and white photographs of Oriental rugs as stimuli. Forgetting rates were generally invariant with age and experience, while the acquisition parameter seemed to vary as a function of specific cultural experiences. Data from the three additional groups were useful in supporting the hypothesis of culture-specific memory skills.From Experiments I and II, and previous research, it was hypothesized that structural features of memory (e.g., short-term store and invariant forgetting rates) may be universal, while control processes or mnemonics in memory are probably culture-specific, or a function of a variety of experiential and cultural factors that surround the growing child.  相似文献   
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