全文获取类型
收费全文 | 23402篇 |
免费 | 111篇 |
国内免费 | 1篇 |
专业分类
23514篇 |
出版年
2023年 | 25篇 |
2022年 | 22篇 |
2020年 | 47篇 |
2019年 | 50篇 |
2018年 | 3533篇 |
2017年 | 2867篇 |
2016年 | 2301篇 |
2015年 | 254篇 |
2014年 | 138篇 |
2013年 | 404篇 |
2012年 | 687篇 |
2011年 | 2479篇 |
2010年 | 2582篇 |
2009年 | 1539篇 |
2008年 | 1795篇 |
2007年 | 2266篇 |
2006年 | 128篇 |
2005年 | 297篇 |
2004年 | 257篇 |
2003年 | 210篇 |
2002年 | 173篇 |
2001年 | 95篇 |
2000年 | 107篇 |
1999年 | 73篇 |
1998年 | 77篇 |
1997年 | 72篇 |
1996年 | 52篇 |
1995年 | 43篇 |
1994年 | 48篇 |
1993年 | 48篇 |
1992年 | 58篇 |
1991年 | 39篇 |
1990年 | 46篇 |
1989年 | 40篇 |
1988年 | 33篇 |
1987年 | 35篇 |
1986年 | 31篇 |
1985年 | 32篇 |
1984年 | 30篇 |
1983年 | 35篇 |
1982年 | 24篇 |
1981年 | 41篇 |
1980年 | 39篇 |
1979年 | 33篇 |
1978年 | 30篇 |
1977年 | 24篇 |
1976年 | 38篇 |
1975年 | 22篇 |
1968年 | 23篇 |
1966年 | 21篇 |
排序方式: 共有10000条查询结果,搜索用时 2 毫秒
121.
A system for monitoring blood pressure or other physiological variables in the unanesthetized and chronically instrumented dog is described. An indwelling catheter attaches to a pressure transducer affixed to the underside of a leather shield, which snaps onto a custom-fitted leather vest worn by the dog. The transducer cable ascends vertically through a hollow, flexible, stainless steel tether, which is attached at the lower end to the leather shield and at the upper end to a fluid and electrical swivel. The swivel is attached to an overhead counterbalanced boom assembly, which moves in concert with the dog, maintaining a constant minimal tension on the tether. The boom assembly is attached to a wall plate via a universal joint approximately 7 ft above floor level. Dogs can be maintained comfortably in this system 24 h/day over periods of months, with freedom of posture and movement, including rotational behavior. The system is economical to construct and provides versatile stimulation and record-ing capability and reliable long-term performance. 相似文献
122.
R. L. Ray S. Lease S. J. Olson D. E. Anderson 《Integrative psychological & behavioral science》1981,16(4):204-211
The purpose of this study was to illustrate the use of time-series analysis with long-term cardiovascular responding. Analyses of two successive 1000-minute mean blood pressure and heart-rate series in five chronically instrumented dogs showed that the autocorrelation function of the original series appeared highly nonstationary and that differencing the data produced a simple autocorrelation pattern which could be successfully modeled with stepwise autoregression. Evidence for reliable individual differences as well as change over sessions is presented and discussed. 相似文献
123.
Dr. Nancy J. Cohen Janette Sullivan Klaus Minde Carole Novak Catherine Helwig 《Journal of abnormal child psychology》1981,9(1):43-54
This study of kindergarten-aged hyperactive children evaluated the effects of three modes of treatment in relation to an untreated control group. The treatments were administered over a 3-month period and included cognitive behavior modification, methylphenidate, and the two treatments combined. A follow-up assessment was done approximately 1 year later at the end of the first grade. Analyses of psychological, rating scale observational, and interview data showed that hyperactive children became less symptomatic over time;the data did not provide evidence indicating that any of the treatments studied was more effective than any other or than no treatment at all.This research was supported by grants from the Ontario Mental Health Foundation (Grant No. 701-76/78) and The Hospital for Sick Children Foundation (Grant No. 77-22). The authors wish to thank Mr. Syl Sauro, of the Etobicoke Board of Education, and Mrs. M. Stijovic, of the Etobicoke Community Health Department, for their cooperation. 相似文献
124.
While considerable research has investigated the relationship of sex and/or sex role to general or trait anxiety, little is known about their relationship to more specific anxiety types. Based on the postulate that sex and sex-role differences may depend on the extent to which an anxiety-producing situation represents a sex-stereotypic domain, the present study compared their relationships to four measures of anxiety: Math anxiety, test anxiety, and two measures of trait anxiety. Subjects were 180 undergraduate students enrolled in introductory psychology courses. Although females reported higher levels of anxiety on all four scales than did males, a discriminant function analysis indicated that math anxiety was the strongest contributor to the separation of the sexes. Significant score differences as a function of sex role were found using the STAI A-Trait scale, and a significant sex × sex-role interaction was found for scores on the S-R Inventory of Anxiousness. Feminine-typed males and undifferentiated females reported highest anxiety levels in comparison to same-sex individuals. Implications for the understanding and treatment of both general and situationally specific anxiety are discussed. 相似文献
125.
Sex-role research has been hampered by a lack of valid and reliable research tools to measure the construct being studied. This article describes the development of a research scale (ISRO) to measure women's sex-role orientation. This 16-item questionnaire has been shown to be internally consistent and to have fairly high temporal stability over 30 days. The high sensitivity (96.2%) and specificity (95.5%) suggest that it differentiates feminist from traditional women. Three factors assess attitudinal domains of conflict between family responsibilities and having a career; male/female division of household responsibilities; and women's work roles outside the home. Education appears to be the strongest predictor of ISRO scores.This study was supported in part by a grant from the American Nurses Foundation. 相似文献
126.
We advocate the use of a family systems approach to premarital pastoral work, involving exploration of the families of origin of the intended spouses. Family systems theory argues that a marriage is like a merger of two corporations, each having its own stockholders; thus, adequate preparation for marriage involves coming to terms with the realities of one's family of origin and that of one's intended spouse. Exploratory techniques include genograms, house tours, family photo albums, and discussions of the rules and rituals in the respective families. Leaving father and mother is the central prerequisite to marriage.Dr. Mitchell is Professor of Pastoral Care and Theology, Eden Theological Seminary, 475 E. Lockwood Ave., Webster Groves, Missouri 63119. Dr. Anderson is Associate Professor of Pastoral Theology, Wartburg Theological Seminary, 333 Wartburg Place, Dubuque, Iowa 52001. 相似文献
127.
Nancy A. Neef Michael S. Shafer Andrew L. Egel Michael F. Cataldo John M. Parrish 《Journal of applied behavior analysis》1983,16(1):81-99
Two experiments are reported in which the relationship between compliance with “do” and “don't” requests was examined with developmentally disabled children. In Experiment 1, a multiple baseline design across subjects with counterbalanced treatment conditions was used to evaluate a compliance training program composed of four phases: (a) baseline, during which no consequences were delivered for compliance, (b) reinforcement for compliance with one targeted “do” request, (c) reinforcement for compliance with one targeted “don't” request, and (d) follow-up with reinforcement on a variable ratio schedule for compliance with any “do” or “don't” request. Results of probes conducted before and after training within each condition indicated that generalized compliance occurred only with requests of the same type as the target exemplar (“do” or “don't”). In Experiment 2, these results were replicated in a classroom setting. Following collection of baseline probe data on student compliance, a teacher training program was successfully implemented to increase reinforcement of compliance first with one “do” and subsequently with one “don't” request of a target student. Results of multiple baseline probes across “do” and “don't” requests indicated that the teacher generalized and maintained reinforcement of compliance with other requests of the same type and to other students, with a resulting increase in student compliance with the type of requests reinforced. The impact of treatment on both teacher and student behavior was socially validated via consumer ratings. Implications of these findings with respect to response class formation and compliance training programs are discussed. 相似文献
128.
129.
According to frequency theories of concept attainment, acquisition of rule-governed concepts depends on discriminating relevant from irrelevant stimulus features on the basis of their respective frequencies of occurrence. Depending on the theorist, the critical frequency counts may be based on occurrence in all stimuli or on occurrence in positive instances only. Experiment 1 held frequency in positive instances constant and varied the frequency of irrelevant features in the negative category. High frequency was associated with impaired performance, but only when concept problems started with a negative instance. Experiment 2 demonstrated that some previous findings in the literature that were thought to support frequency theory also depended on problems starting with a negative instance. These findings are not easily reconciled with existing frequency theories. We attribute our results to high intercategory similarity, which is a correlate of high frequency of irrelevant features. In the context of a hypothesis-testing theory, we propose that a negative start stimulus proactively interferes with memory for information in the initial positive instance and that the extent of the interference depends on how similar negative instances are to positive instances. 相似文献
130.