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   23031篇
  免费   1174篇
  国内免费   17篇
  2020年   330篇
  2019年   363篇
  2018年   521篇
  2017年   562篇
  2016年   570篇
  2015年   433篇
  2014年   484篇
  2013年   2029篇
  2012年   854篇
  2011年   959篇
  2010年   563篇
  2009年   551篇
  2008年   726篇
  2007年   723篇
  2006年   622篇
  2005年   559篇
  2004年   554篇
  2003年   511篇
  2002年   532篇
  2001年   801篇
  2000年   809篇
  1999年   564篇
  1998年   272篇
  1997年   256篇
  1996年   229篇
  1995年   221篇
  1994年   190篇
  1993年   199篇
  1992年   438篇
  1991年   378篇
  1990年   394篇
  1989年   383篇
  1988年   365篇
  1987年   330篇
  1986年   351篇
  1985年   355篇
  1984年   292篇
  1983年   246篇
  1982年   195篇
  1981年   199篇
  1979年   238篇
  1978年   204篇
  1977年   195篇
  1975年   233篇
  1974年   277篇
  1973年   241篇
  1972年   238篇
  1969年   211篇
  1968年   218篇
  1966年   192篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
811.
This study compared the effectiveness and efficiency of simultaneous prompting with and without error correction during daily probe sessions in teaching science vocabulary words. The teacher presented the vocabulary word definitions as instructive feedback during training sessions. Five 16–17 year old students with disabilities participated in an adapted alternating treatments design that evaluated the simultaneous prompting strategy, error correction and instructive feedback. Instruction occurred in a group format using choral responding. The results indicate that (a) all students learned to read the vocabulary words, (b) simultaneous prompting with error correction was slightly more efficient for three of the five subjects in learning the targeted words, and four of the five students made fewer errors in this condition, (c) all students preferred simultaneous prompting with error correction over simultaneous prompting without error correction, (d) words mastered in both conditions generalized equally, (e) there were minimal differences between the two conditions in the collected maintenance data, and (e) students experienced only minimal improvement in their ability to define vocabulary words (instructive feedback). Discussion focuses on issues for further research and implications for instructional practice with simultaneous prompting, error correction and instructive feedback.  相似文献   
812.
Feminist legal theory provides a healthy skepticism toward legal doctrine and insists that we reexamine even formally gender-neutral rules to uncover problematic assumptions behind them. The article first outlines feminist legal theory from the perspectives of liberal, cultural, and radical feminism. Examples of how each theory influences legal practice, case law, and legislation are highlighted. Each perspective is then applied to a contemporary bioethical issue, egg donation. Following a brief discussion of the common themes shared by feminist jurisprudence, the article incorporates a narrative reflecting on the integration of the common feminist themes in the context of the passage of the Maryland Health Care Decisions Act. The article concludes that gender does matter and that an understanding of feminist legal theory and practice will enrich the analysis of contemporary bioethical issues.  相似文献   
813.
PsyCLE is a 3-year project involving over 30 United Kingdom universities to develop multimedia resources for introductory psychology courses. Our goal is to support active learning and encourage students to form a sound understanding of concepts under study. The developments focus on interactive tasks, illustrative case study material, and tools to support critical thinking and analysis. We discuss the rationale for the approach adopted and describe the developed resources and their evaluation and use.  相似文献   
814.
It is now relatively easy to implement pupillometry in social psychological research. We describe a system in which a Macintosh computer presents visual and auditory stimuli to subjects while monitoring an infrared pupillometer. The computer records information on subject, task, and pupil diameter into a data file for input into standard statistical analysis programs. Pupil diameter is measured continuously while subjects respond to stimuli that last for several seconds or minutes. A demonstration experiment verifies the usefulness of the system. The ability of the Macintosh computer to easily handle visual and auditory stimuli and to record responses lasting a considerable length of time makes the system well suited for studying pupil responses to complex social stimuli. This system is also well suited for the researcher initiating a research program using pupillometry. Ease of operation makes using a large number of subjects feasible.  相似文献   
815.
An injection olfactometer for human psychophysical experiments is described. The olfactometer is capable of presenting, either mono- or birhinally, single odorants and binary mixtures. The pulse form of the olfactory stimulus at the exit of the olfactometer approaches a rectangular form, which makes the olfactometer well suited for olfactory reaction time measurements. Since stimulation periods are independent of the subject’s inhalation, time-intensity measurements over prolonged periods of time are possible as well. In the second part of this paper, a new technique is described for the measurement of the stimulus pulse form at the exit of the olfactometer.  相似文献   
816.
On multiple occasions, rats were administered diazepam (2.0 mg/kg, ip) followed 30 min thereafter by yohimbine hydrochloride (2.5 or 5.0 mg/kg) or isotonic saline (forward conditioning groups). Three additional groups (backward conditioning controls) were given equivalent injections, but in reverse order. After eight such pairings, the effects of a single injection of diazepam on motor performance (balancing on a rotating drum) was assessed. Rats that had received either dose of yohimbine during forward conditioning trials maintained their balance longer than the saline controls. After four additional conditioning trials, the animals’ activity patterns in a plus-maze screening test for anxiolytics were examined. Placed into the maze after a single test injection of isotonic saline, the behavior of all groups was virtually identical: less than 16% of total entries into or time spent in the four arms of the maze was spent in the two “open” arms (unprotected by surrounding walls). When tested in the maze again, but 35 min after a single injection of diazepam, the groups that had received diazepam but not yohimbine during the conditioning phase exhibited the expected increase in open-arm activity, and equivalent increases were found in backward conditioning groups. However, the group previously conditioned with 2.5 mg/kg of yohimbine following diazepam also showed an increased open-arm activity when tested with diazepam alone, but it was significantly greater than that seen in the control group. In contrast, the group conditioned with 5.0 mg/kg yohimbine following diazepam exhibited no effect of diazepam upon their plus maze activity; consequently, these animals spent less time in the open arms than either of the other groups. Yohimbine alone normally decreases open-arm activity (a putative “anxiogenic” effect) in a linear dose-dependent fashion. The fact that it had a bidirectional conditional effect on the diazepam cue drug demonstrates that a conditional response in drug → drug conditioning cannot always be predicted on the basis of the behavioral response to the signaled drug. Consideration is given to possible reasons for these effects of diazepam → yohimbine pairings in terms of the known neuropharmacological properties of yohimbine.  相似文献   
817.
We explore a model that examines how personal and environmental variables explain violent behavior by adolescents. Repeated interviews with youths from 1984–1992 from 10 cities across the United States provided the data. These interviews first occurred with 2,787 youths when they were adolescents (1984–85 and 1986–87) and the interviews were repeated on a subsample of 602 youths when they were young adults (1989–90 and 1991–92). Longitudinal multivariate analyses showed that almost a third of the variance in adolescent violent behaviors was predicted by a combination of personal variables (gender, substance misuse) and environmental variables (history of child abuse, stressful events, traumatic events, and city rates of unemployment). Further, almost a third of the variance in change in violent behaviors from year to year was predicted by prior violent behavior and a combination of personal variables (gender, suicidality, and substance misuse) and environmental variables (stressful events).  相似文献   
818.
The effects of embedding a constant time delay procedure into an independent seat work activity and using instructive feedback were evaluated in this study. Seven students with mild disabilities participated in the study that occurred in their special education classroom. A multiple probe design across sets of target behaviors was used, and students' responses to instructive feedback stimuli were evaluated during each probe condition. The procedures were implemented with a high degree of fidelity, and the results indicate that (a) the students acquired the target behaviors taught with the constant time delay procedure that was embedded into independent seat work, and (b) the students acquired some but not all of the responses to the instructive feedback stimuli. These findings are discussed in terms of using instructive feedback in classrooms and future research on instructive feedback.  相似文献   
819.
Subjects were 288 adolescents and adults with end-stage renal disease who were candidates for kidney transplantation, a group identified at risk for noncompliance. The purpose was to examine racial and ethnic variations in coping—variables that may underlie noncompliance and impact upon health outcome. Secondarily, the relationship between depression and particular styles of coping was investigated. Race/Ethnicity was divided into three categories: Black/Non-Hispanic, White/Non-Hispanic, and Hispanic. Coping and depression were assessed using the COPE and Beck Depression Inventory, respectively. Results indicated that Hispanic and Black subjects were more likely to use maladaptive styles of coping and less likely to use adaptive coping than were White subjects and that Black subjects reported more physical symptoms of depression. These findings point to possible mechanisms underlying the occurrence of noncompliance and resulting poorer health outcome for individuals of different racial and ethnic groups.  相似文献   
820.
This study investigated the prevalence of traumatic brain injury (TBI) in an inpatient psychiatric population. We hypothesized increased prevalence of TBI relative to the general population due to a variety of risk factors observed in psychiatric patients. One hundred (mean age = 34) psychiatric inpatients completed the revised Head Injury Questionnaire. Chart review of 17 subjects reporting injuries established whether injuries were documented in medical records. Sixty-eight percent of this psychiatric population reported one or more injuries in which they were unconscious or dazed. This number is higher than the prevalence in the general population. Injuries were generally of mild to moderate severity; multiple injuries were common. Chart review of 17 subjects reporting TBI indicated that histories of TBI had not been noted in the medical record. Finally, 63% of TBI subjects reported that their injury predated the onset of their psychiatric symptoms. These results suggest a possible role of TBI in psychiatric symptomatology and have implications for psychiatric treatment in this population.  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