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261.
The major objectives of this study were to determine the characteristics of creativity development of Chinese children, the creative organizational climate of Chinese schools, and the relations among them. The results provided evidence that the creativity scores of children in elementary school were significantly higher than those of children in middle school. The teachers' evaluation of the creative organizational climate of the elementary school was significantly higher than that of the middle school. When the two variables were analyzed together, both the creative organizational climate of schools and the creative thinking development of children decreased during the children's development. Moreover, the creativity and climate scores were highly correlated, and the results from a path analysis suggested that a school's creative organizational climate has a significant impact on all seven dimensions of creativity measured in this study.  相似文献   
262.

In the second (and expanded) version of Origin of the Species, Darwin introduces the term “advanced progressive development” in an attempt to describe the development of the more complex species from the simpler ones. More than 100 years have passed since Darwin tried to qualify and conceptualize the directional question of evolution, and very little progress has been made regarding the subject. The appearance of the species, from the simple to the more complex, is today an empirical fact, one which is no longer dependent upon any theory, including that of Darwin. This work examines the subject of advanced development in evolution by attempting to answer a few basic questions: What parameters may be used to evaluate complexity? Can any rules or order be identified as to the development of the species? Is the mechanism of “natural selection” sufficient to explain the direction or ‘purpose’ of evolution? Can the human race be included within the “rules” of Darwin's evolutionary theory?

The purpose of this essay is to develop and represent a new conceptual framework. Through this, it will be possible to offer a principle answer to all four questions.  相似文献   
263.
Behavioral stressors may inhibit sodium excretion, potentially increasing plasma volume and elevating blood pressure during chronic exposure. Blood pressure regulation may be especially deranged during manipulations that further challenge the kidney, such as a diet high in salt content. The effects on blood pressure and other variables of combined behavioral stress (food/shock conflict) and dietary salt (12 g NaCl per day; 218 mEq Na+ per day) were examined in adult male baboons over the course of 1 year. Mean arterial pressure was not significantly elevated over baseline after 5 months of high dietary salt alone (6 +/- 5 mmHg) but was maximally elevated by an average of 17 (+/- 3 SEM) mmHg after 5 months of combined salt and conflict stress. Control baboons showed no significant trends in mean arterial pressure across the same time period. Individual subjects whose blood pressure was "salt+stress resistant" or "salt+stress sensitive" were differentiated by their degree of pressure diuresis and natriuresis, urinary free cortisol, and a behavioral index of stress sensitivity. The data indicate additive effects of chronic high dietary salt intake and behavioral stressors on blood pressure in nonhuman primates that are dependent on renal function and pituitary-adrenocortical activity.  相似文献   
264.
小学三~五年级儿童创造性思维训练的实验研究   总被引:4,自引:0,他引:4  
研究表明学龄儿童已具有一定的创造力 ,因此要重视并激发儿童的创造活动。本研究在前人研究的基础上 ,自编了一套创造性思维训练题 ,并设计了传统讲授教学法和促进、诱导学生自我发现的发现法二种训练方法 ,同时与未经训练的对照组比较 ,考察了小学三~五年级儿童创造性思维的几个维度和总体水平上在训练前后的变化。结果表明 :经过一个学期的短期训练 ,无论在创造性思维的不同维度上还是在总体水平上 ,都对小学儿童产生了显著的影响 ,而所设计的二种训练方法在短期效果上没有明显差异。  相似文献   
265.
Rats were trained on a free-operant procedure in which shock duration was controlled by responses within a limited range of interresponse times. Shocks of 1.6-mA intensity occurred randomly with average density of 10 shocks per minute. As long as interresponse times were 15 seconds or less, any shocks received were at the briefer of two durations (.3 second). Whenever interresponse times exceeded 15 seconds, any shocks received were at the longer duration (1.0 second). For six of eight animals, avoidance responding developed quickly and reached levels of better than 90%. Four yoked animals stopped responding within the first few sessions. Shock duration reduction without change in shock probability or intensity was sufficient for the acquisition and maintenance of avoidance responding.  相似文献   
266.
Negative reinforcement with shock-frequency increase   总被引:5,自引:5,他引:0       下载免费PDF全文
Two avoidance-conditioning experiments in which responding delayed shocks are reported. Rats receiving an average of two shocks per minute (imposed condition) could produce, by pressing a bar, a 3-min alternate condition. Six (Experiment I) or more (Experiment II) shocks occurred in the alternate condition. All shocks in the alternate condition were delayed and delivered at 1-sec intervals. With long delays, all subjects produced the alternate condition and spent a large percentage of each session in the alternate condition. The first experiment demonstrated that the longer the delay from onset of the alternate condition to onset of the shocks, the more session time spent in the alternate condition. The second experiment indicated that despite increased shock frequency, behavior is acquired and maintained when responding leads to sufficient delay. Individual subjects produced the alternate condition by bar pressing in essentially one of two patterns. One pattern, termed postshock, involved bar pressing immediately after shock; the other, termed posttransition, involved responding immediately after the transition from the alternate to the imposed condition. These results indicate that shock-frequency reduction is not necessary for avoidance conditioning; delay to shock onset is sufficient.  相似文献   
267.
Responding maintained in squirrel monkeys under 5-min fixes-interval schedules of either food presentation or termination of a visual stimulus associated with electric-shock delivery was suppressed by presenting an electric shock for every thirtieth response (punishment). In monkeys responding under the schedule of food presentation, d-amphetamine sulfate only further decreased punished responding, and pentobarbital sodium markedly increased punished responding, as expected from previous reports. In monkeys responding under the schedule of stimulus-shock termination, however, the effects of the two drugs were opposite: d-amphetamine markedly increased punished responding, whereas pentobarbital only decreased responding. Thus, the effects of these drugs on punished responding were different depending on the type of event maintaining responding. These and previous results indicate that it may be misleading and inaccurate to speak of the effects of drugs on "punished responding" as though punishment were a unitary phenomenon. As with any behavior, the effects of drugs and other interventions on punished responding cannot be accurately characterized independently of the precise conditions under which the behavior occurs.  相似文献   
268.
Integrated delays to shock as negative reinforcement   总被引:4,自引:4,他引:0       下载免费PDF全文
Rats were shocked at the rate of two per minute until they pressed a lever. In Experiment I, shocks were delivered at variable-time intervals averaging 30 sec; in Experiment II, shocks were delivered at fixed-time intervals of 30 sec. A response produced an alternate condition for a fixed-time period. The shock frequency following a response, calculated over the whole alternate condition, was two per minute. The pattern of shocks in the alternate condition was controlled so that the first shock occurred at the same time as it would have occurred had the response not been emitted; the remaining shocks were delayed until near the end of the alternate condition. Bar pressing was acquired in both experiments. This finding is not explained by two-factor theories of avoidance and is inconsistent with the notion that overall shock-frequency reduction is necessary for negative reinforcement. The data imply that responding is determined by the integrated delays to each shock following a response versus the integrated delays to shock in the absence of a response.  相似文献   
269.
Response-shock delay as a reinforcer in avoidance behavior   总被引:2,自引:2,他引:0       下载免费PDF全文
After rats received preliminary training to avoid shock on a discrete-trial retractable-bar avoidance procedure, the procedure was changed such that responses retracted the lever but did not affect the rate of shock. Responses only delayed the onset of shock. About half of the animals under these procedures responded consistently on almost 100% of the discrete-trial cycles over days. When short latencies maximized the response-shock delay, animals tended to make short-latency responses. When long latencies maximized the response-shock delay, animals tended to make long-latency responses. When all response latencies produced the same response-shock delay, animals made differing average-latency responses. And, when responses did not delay shock, most of the animals primarily engaged in shock-elicited responding while the other animals engaged in preshock responding.  相似文献   
270.
Five rats were submitted to a signaled free-operant avoidance contingency. Throughout the experiment, shock intensity was varied from 0.1 to 8.0 mA, with shock duration constant at 200 milleseconds. Results indicate: (a) an all-or-none effect of shock intensity on response and shock rates, on percentage of shocks avoided, and on frequency of occurrence of responding during the preshock stimulus; and (b) no systematic effect of shock intensity on stimulus control, measured either by the percentage of stimulus presentations accompanied by a response or by the percentage of responses that occurred during those preshock stimuli. Such results indicate that for each subject there is a minimum shock intensity necessary to establish and maintain avoidance responding; intensities higher than this minimum value have little or no effect on responding (with an upper limit for those strong intensities with a general disruptive effect on behavior).  相似文献   
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