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   24128篇
  免费   969篇
  国内免费   11篇
  2020年   230篇
  2019年   298篇
  2018年   427篇
  2017年   447篇
  2016年   480篇
  2015年   377篇
  2014年   391篇
  2013年   2030篇
  2012年   709篇
  2011年   741篇
  2010年   442篇
  2009年   423篇
  2008年   564篇
  2007年   625篇
  2006年   548篇
  2005年   511篇
  2004年   481篇
  2003年   481篇
  2002年   509篇
  2001年   784篇
  2000年   745篇
  1999年   570篇
  1998年   241篇
  1996年   256篇
  1995年   232篇
  1992年   471篇
  1991年   479篇
  1990年   461篇
  1989年   428篇
  1988年   454篇
  1987年   410篇
  1986年   411篇
  1985年   432篇
  1984年   328篇
  1983年   310篇
  1982年   237篇
  1981年   236篇
  1979年   376篇
  1978年   286篇
  1977年   241篇
  1975年   296篇
  1974年   376篇
  1973年   383篇
  1972年   298篇
  1971年   291篇
  1970年   290篇
  1969年   259篇
  1968年   359篇
  1967年   320篇
  1966年   291篇
排序方式: 共有10000条查询结果,搜索用时 140 毫秒
861.
An apparatus was developed to study social reinforcement in the rat. Four Long-Evans female rats were trained to press a lever via shaping, with the reinforcer being access to a castrated male rat. Responding under a fixed-ratio schedule and in extinction was also observed. Social access was found to be an effective reinforcer. When social reinforcement was compared with food reinforcement under similar conditions of deprivation and reinforcer duration, no significant differences were observed.  相似文献   
862.
Male Siamese fighting fish, Betta splendens, swam through a ring in an aquarium, breaking a photocell beam and initiating an unsignaled, resetting delay interval. Following delays of 0 s, 10 s, or 25 s, a 15-s mirror presentation released an aggressive display by the fish. Swimming through the ring increased in the absence of either a period of acclimatization to the reinforcer (analogous to magazine training when appetitive reinforcers are used) or explicit training of the response by the experimenters. Response rates were a decreasing function of delay duration. Other fish exposed to a schedule of response-independent mirror presentations failed to acquire and maintain the response. The results demonstrate the robustness and generality of the phenomenon of response acquisition with delayed reinforcement. They further qualify earlier observations about behavioral mechanisms involved in the phenomenon.  相似文献   
863.
Compliance with postpartum visits after teenage births in the US was examined among 289 Hispanic teenagers, of whom 127 were born in Mexico or border towns, who delivered at Harris County Hospital District and scheduled postpartum appointments at the Teen Health Clinic. The mean age was 17.31 years for mothers and 21.95 years for fathers. 56.7% (164) were married. 49.8% lived with husbands, 25.8% with parents, 22.3% with friends/relatives, and 2.1% alone. 74.7% stated that they had no social supports. 88.9% had a term delivery, 8.3% a preterm delivery, and 2.8% a fetal loss. 67.5% were first births, 5.5% had a previous abortion, and 3.1% had a previous miscarriage. 23.2% had a previous child, and 0.7% had a previous preterm delivery. Some form of prenatal care was received by 85.1%. 34.3% reported no further educational plans. 17.3% (50) returned for a scheduled postpartum visit. Mothers with a prior history of a premature birth or miscarriage were more likely to return postpartum compared to mothers with a first or prior birth. The differences are marginally significant. None of the mothers with a prior abortion returned. 34.9% of the returning teen mothers were more likely to have had prenatal care. Returning mothers also were a larger percentage of those with no future educational plans. 13.4% of returning mothers had an available social support system. Country of origin was not associated with support systems, prenatal care, return status, educational plans, pregnancy history, or current birth outcome. Out of the 50 returning, 20 were Mexican-born and married. Only Mexican marital status was found to be a significant variable explaining differences. Marital status had no effect on the 26 US native-born returnees. 92% of the Mexican-born teens were married and had a support system. The most dramatic feature of this study is the high level of noncompliance among both US-born and Mexican-born adolescents. There were few distinguishing features between these two groups. Return status was affected by very few features and was achieved by a very small percentage of the study population. The suggestion is made that poverty, a lack of health insurance, and poor knowledge of English, as representative of cultural dissimilarity, may be responsible for poor use of preventive care.  相似文献   
864.
The purpose of this investigation was to assess the influence of White racial identity attitudes on racism. A total of 234 White undergraduate students participated in this investigation. The students completed the White Racial Identity Attitude Scale (Helms & Carter, 1990) and the New Racism Scale (Jacobson, 1985). Consistent with findings in previous research, White racial identity attitudes were predictive of racism. We also found gender and age differences in White racial identity attitudes. Implications of these findings are discussed in terms of the role of counselors in addressing racial awareness on college campuses.  相似文献   
865.
The authors examined the association between demographic variables and self-reported multicultural counseling competencies among counselors. A national sample of 220 counselors affiliated with university counseling centers participated in this investigation. Counselors responded to 40 Likert-type statements about multicultural awareness, knowledge, skills, and relationships. Results from a series of multivariate and univariate analyses indicated that Asian American and Hispanic counselors reported more multicultural knowledge than did White counselors, and African American, Asian American, and Hispanic counselors reported more competence in multicultural awareness and relationships than did White counselors. No effects were found for other demographic variables. Implications of these findings are discussed.  相似文献   
866.
The present study reports on a clinical instrument designed for assessing self-efficacy in alcoholics. In contrast to studies that construct general measures, it was proposed that taking an individualized approach to assessment might offer an effective methodology. Thirty-four alcoholics in an outpatient, behaviorally oriented treatment program participated as subjects. During therapy, an Individualized Self-Efficacy Survey (ISS) was developed for each subject. The ISS was developed by (a) administering the Drinking Patterns Questionnaire (DPQ) to identify important problem areas (e.g., work, children, marital) and specific drinking antecedents and (b) constructing a 15-item scale using each drinker's most important cues. The utility of having clients choose their own items was supported by finding a significant relationship between problem areas identified as important on the DPQ and the areas reported as surrounding relapse. ISS ratings were reflective of efficacy changes during treatment, while posttreatment ISS scores were predictive of subsequent relapse. Situation-specific prediction of relapse was not found. The advantages of this methodology for clinical use are discussed, while general directions for future research are suggested.  相似文献   
867.
SPEECH PERCEPTION AS A TALKER-CONTINGENT PROCESS   总被引:2,自引:0,他引:2  
Abstract— To determine how familiarity with a talker's voice affects perception of spoken words, we trained two groups of subjects to recognize a set of voices over a 9-day period One group then identified novel words produced by the same set of talkers at four signal-to-noise ratios Control subjects identified the same words produced by a different set of talkers The results showed that the ability to identify a talker's voice improved intelligibility of novel words produced by that talker The results suggest that speech perception may involve talker-contingent processes whereby perceptual learning of aspects of the vocal source facilitates the subsequent phonetic analysis of the acoustic signal  相似文献   
868.
The accreditation standards outlined in the article are used by the International Association of Counseling Services, Inc., as the basis for the formal accreditation of college and university counseling programs throughout the United States and Canada. They reflect the program elements and practice standards that are deemed essential in a counseling center that provides high-quality services to students.  相似文献   
869.
The adolescent substance abuser, like adult addicts, is most commonly considered from the perspective of the disease model. The usefulness of the disease model in conceptualizing adolescent substance abuse is questioned, and an alternative view of the topic is set forth. Substance abuse, is regarded as an adaptive aspect of the ongoing interactive processes within the family. The developmental process of the adolescent substance abuser is seen as a functional dynamic in the family's preservation. Three characteristic elements of parental interaction common to the development of adolescent substance abuse are highlighted.An earlier version of this paper was presented at the Texas Association for Marriage and Family Therapy annual conference on January 28, 1993 in Houston Texas.a research associate and director of the Don D. Jackson Archive at the Mental Research Institute, Palo Alto, CA. Authors are listed alphabetically.  相似文献   
870.
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