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   1611篇
  免费   356篇
  国内免费   191篇
  2024年   10篇
  2023年   58篇
  2022年   41篇
  2021年   59篇
  2020年   109篇
  2019年   110篇
  2018年   102篇
  2017年   96篇
  2016年   87篇
  2015年   58篇
  2014年   80篇
  2013年   238篇
  2012年   49篇
  2011年   61篇
  2010年   42篇
  2009年   46篇
  2008年   50篇
  2007年   66篇
  2006年   70篇
  2005年   67篇
  2004年   46篇
  2003年   57篇
  2002年   50篇
  2001年   48篇
  2000年   18篇
  1999年   33篇
  1998年   22篇
  1997年   29篇
  1996年   28篇
  1995年   23篇
  1994年   30篇
  1993年   24篇
  1992年   17篇
  1991年   22篇
  1990年   14篇
  1989年   7篇
  1988年   12篇
  1987年   6篇
  1986年   19篇
  1985年   12篇
  1984年   14篇
  1983年   12篇
  1982年   19篇
  1981年   14篇
  1980年   18篇
  1979年   11篇
  1978年   12篇
  1977年   15篇
  1976年   17篇
  1975年   10篇
排序方式: 共有2158条查询结果,搜索用时 15 毫秒
891.
This study examined the effects of an intensive training program on the toothbrushing skills of three preschool children, using both performance measures and outcome (plaque level) indicators. Toothbrushing was broken into 16 steps that involved actual manipulation of the brush in the mouth. Correct brushing included four criteria: (a) appropriate angle of bristles, (b) appropriate motion of brush, (c) appropriate tooth surface, and (d) minimum duration of brushing. Training included instructions, a three-phase modeling procedure, physical guidance, and reinforcement. Results of a multiple baseline design across subjects showed that the children completed an average of 8.6% of the steps prior to training, as compared with an average of 95.8% of the steps following training. Plaque levels decreased from an average of 58% during baseline to 24.6% after training. Follow-up measures revealed that 86.6% of the steps were maintained. The study demonstrated that the effectiveness of the procedures in teaching very young children a complex motor skill that is essential to their future health.  相似文献   
892.
This study evaluated contingent reinforcement for benzodiazepine-free urines as a therapeutic intervention for promoting reduced use of supplemental benzodiazepine drugs among methadone maintenance outpatients. Ten methadone maintenance patients were selected for participation on the basis of positive urinalysis results. During a 12-week intervention period these patients were offered clinic privileges, including monetary payments or methadone take-home doses, contingent on benzodiazepine negative urinalysis test results. Eight of ten participants responded to the intervention with at least 2.5 weeks of consecutive clean urines. An increase in benzodiazepine-negative tests during the contingent reinforcement period was significant for the group as a whole. The results suggest that more widespread application of contingent reinforcement procedures may be warranted in drug abuse treatment clinics.  相似文献   
893.
Choice and behavioral patterning   总被引:3,自引:3,他引:0       下载免费PDF全文
Ten pigeons pecked left and right keys in a discrete-trials experiment in which access to food was contingent upon changeovers to the right key after particular runs of left-key pecks. In each of three sets of conditions, two run lengths were reinforced according to a concurrent variable-interval schedule: reinforcement followed runs of either 1 or 2, 1 or 4, or 2 or 4 left-key pecks preceding changeovers. The intertrial interval separating successive pecks was varied from .5 to 10.0 sec, and the relative frequency of reinforcement for the shorter of the two reinforced runs was varied from 0 to .75. The contingencies established local behavioral patterning that roughly approximated that required for reinforcement. For a fixed pair of reinforced run lengths, preference for the shorter of the two frequently increased as the intertrial interval increased and therefore as the minimum temporal durations of both reinforced runs increased. Preference for the shorter of the two also increased as its corresponding relative frequency of reinforcement increased. Both of these effects on preference were qualitatively similar to corresponding effects in previous research with two different kinds of reinforced behavioral patterns, interresponse times and interchangeover times. In all these experiments, analytical units were found in the temporal patterns of behavior, not in the behavior immediately contiguous with a reinforcer. It is suggested that a particular local temporal pattern of behavior is established to the extent to which it is repeatedly remembered when reinforcers are delivered, regardless of whether the delivery of a reinforcer is explicitly contingent upon that pattern.  相似文献   
894.
An analogue setting for assessing dental fear involving a videotaped simulated dental operation was evaluated in terms of its capability of eliciting differential physiological arousal (Palmer Sweat Index) between high- and low-fear subjects, identified by self-reports of dental fear. Results showed high-fear subjects to exhibit significantly greater palmar sweating than did low-fear subjects, females to respond more than males, and a differential response across groups at different points during the simulated operation. High-fear subjects also gave verbal reports of greater physiological arousal and general anxiety while viewing the operation than did low-fear subjects.  相似文献   
895.
An unobtrusive observation system was developed to determine the extent to which dental professionals in two communities provided lead shielding to patients during X-ray exams. A lengthy baseline revealed low and irregular provision of shielding among half of these professionals. Subsequently, a program was undertaken by a consumer's group in which these professionals were requested to provide shielding and were given confidential feedback regarding its use during the baseline period. The provision of shielding dramatically increased at all offices and was maintained throughout a follow-up period extending to more than 9 months after the program's implementation. Little or no generalized effect was observed in the occurrence of three collateral behaviors that were also assessed throughout the study.  相似文献   
896.
This study assessed the effects of a flexible work schedule ("flextime") on time allocated to children and spouse by federal workers. Direct behavioral observations of family, home, and work functions were precluded because of the cost involved in observing many people for long periods of time. In order to obtain detailed individual data, participants completed hour-by-hour activity logs a mean of twice per week for 35 weeks. Participants received prior training on log completion, initial feedback on the detail of their log entries, and were prompted to complete the forms. Four different procedures assessing reliability indicated a corroboration rate of 80% with other sources. Log data were reliably reduced to nine categories such as "PM time with children" and 37 subcategories such as "time at dinner." The log data were presented in time-series form and the use of a quasi-experimental design showed that participants who altered their work schedule were able to spend more PM time with their families. The log data demonstrated that the capacity exists to assess closely the effects of large-scale changes at a micro-behavioral level, but other methods are needed to make complex self-reporting systems less expensive and more capable of immediate monitoring of the intervention's effects.  相似文献   
897.
Undermatching and contrast within components of multiple schedules   总被引:7,自引:7,他引:0       下载免费PDF全文
Six multiple variable-interval schedules each comprised one variable-interval sixty second component and an alternated component which was varied. Four pigeons' responses were recorded in five successive subintervals of each component. Response rate changes across subintervals revealed instances of local contrast and small local induction effects in the changed component. In the constant component, smaller local contrast and larger local induction effects obtained. Accordingly, the magnitude of behavioral contrast, defined as an inverse relation between response rate in the constant component and reinforcement rate in the changed component, did not change reliably across subintervals of the constant component. Ratios of response rates in initial subintervals were highly sensitive to reinforcement ratios. Sensitivity decreased sharply over the first two-fifths of the components and remained constant for the remainder. The results demonstrated that changes in multiple schedule sensitivity are a function of time since the alternation of successive components.  相似文献   
898.
According to theoretical accounts of behavioral momentum, the Pavlovian stimulus—reinforcer contingency determines resistance to change. To assess this prediction, 8 pigeons were exposed to an unsignaled delay-of-reinforcement schedule (a tandem variable-interval fixed-time schedule), a signaled delay-of-reinforcement schedule (a chain variable-interval fixed-time schedule), and an immediate, zero-delay schedule of reinforcement in a three-component multiple schedule. The unsignaled delay and signaled delay schedules employed equal fixed-time delays, with the only difference being a stimulus change in the signaled delay schedule. Overall rates of reinforcement were equated for the three schedules. The Pavlovian contingency was identical for the unsignaled and immediate schedules, and response—reinforcer contiguity was degraded for the unsignaled schedule. Results from two disruption procedures (prefeeding subjects prior to experimental sessions and adding a variable-time schedule to timeout periods separating baseline components) demonstrated that response—reinforcer contiguity does play a role in determining resistance to change. The results from the extinction manipulation were not as clear. Responding in the unsignaled delay component was consistently less resistant to change than was responding in both the immediate and presignaled segments of the signaled delay components, contrary to the view that Pavlovian contingencies determine resistance to change. Probe tests further supported the resistance-to-change results, indicating consistency between resistance to change and preference, both of which are putative measures of response strength.  相似文献   
899.
We explored cross-sectionally the roles in bipolar spectrum symptomatology of two broad motivational systems that are thought to control levels of responsiveness to cues of threat and reward, the Behavioral Inhibition System (BIS) and the Behavioral Activation System (BAS). Undergraduate students (n = 357) completed questionnaires regarding (a) bipolar spectrum disorders [the General Behavior Inventory (GBI), a well-established clinical screening measure], (b) current depression and mania symptoms (the Internal State Scale; ISS), and (c) BIS/BAS sensitivities (the BIS/BAS scales). Validated cutoff scores on the GBI were used to identify individuals at risk for a mood disorder. It was hypothesized that, among at-risk respondents, high BAS and low BIS levels would be associated with high current mania ratings, whereas low BAS and high BIS would be associated with high current depression ratings. Multiple regression analyses indicated that, among at-risk individuals (n = 63), BAS accounted for 27% of current mania symptoms but BIS did not contribute. For these individuals, BAS and BIS were both significant and together accounted for 44% of current depressive symptoms.  相似文献   
900.
This study examines the relationship of three workaholism components (work involvement, feeling driven to work, work enjoyment) proposed by Spence and Robbins (1992) and a variety of work and psychological well being outcomes. Workaholism components generally had significant relationships with these outcome measures, controlling for personal and situational factors. Feeling driven was more likely to be associated with negative well-being outcomes; work enjoyment more likely associated with positive work outcomes.  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