全文获取类型
收费全文 | 167210篇 |
免费 | 7666篇 |
国内免费 | 156篇 |
专业分类
175032篇 |
出版年
2021年 | 1497篇 |
2020年 | 2793篇 |
2019年 | 3458篇 |
2018年 | 3459篇 |
2017年 | 3898篇 |
2016年 | 4576篇 |
2015年 | 3933篇 |
2014年 | 4806篇 |
2013年 | 23518篇 |
2012年 | 4378篇 |
2011年 | 3454篇 |
2010年 | 3808篇 |
2009年 | 4742篇 |
2008年 | 3627篇 |
2007年 | 3142篇 |
2006年 | 3829篇 |
2005年 | 3812篇 |
2004年 | 3346篇 |
2003年 | 2974篇 |
2002年 | 2781篇 |
2001年 | 3156篇 |
2000年 | 3021篇 |
1999年 | 3028篇 |
1998年 | 2819篇 |
1997年 | 2656篇 |
1996年 | 2572篇 |
1995年 | 2412篇 |
1994年 | 2368篇 |
1993年 | 2335篇 |
1992年 | 2471篇 |
1991年 | 2318篇 |
1990年 | 2178篇 |
1989年 | 2115篇 |
1988年 | 2085篇 |
1987年 | 2112篇 |
1986年 | 2094篇 |
1985年 | 2302篇 |
1984年 | 2428篇 |
1983年 | 2247篇 |
1982年 | 2339篇 |
1981年 | 2313篇 |
1980年 | 2145篇 |
1979年 | 2053篇 |
1978年 | 2118篇 |
1977年 | 2105篇 |
1976年 | 1884篇 |
1975年 | 1901篇 |
1974年 | 1957篇 |
1973年 | 1763篇 |
1972年 | 1411篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
As more children with cancer survive, the importance of facilitating school reintegration as a part of maximizing the quality of life has become evident. Workshops have been presented to school personnel to acquaint them with the issues facing cancer patients and their families, but there are gaps in our knowledge of what school personnel really need or want to know. In this study, 18 teachers of children with cancer and 15 teachers with no prior contact with students with cancer completed a questionnaire designed to assess needs, beliefs, and priorities with regard to working with cancer patients in the classroom. Significant findings included: (a) a consensus that a certain core of information about medical/psychological issues would be useful, and presentation of such information by psychologists and medical personnel working with such families would be optimal; (b) teachers having cancer patients as students were less likely to see the adaptation of siblings as an important issue; (c) teachers associated working with a student with cancer with less stress and demands on their time than predictable from previous studies; and (d) cancer patients as a whole were rated as having fewer behavioral, emotional, and learning problems than randomly selected students without a major illness, suggesting a "halo effect" or contradiction of some literature. Preliminary findings are detailed and implications are discussed for those attempting to help teachers facilitate students' adjustment to school following diagnosis and treatment of cancer. 相似文献
993.
A quasi-nonmetric method for multidimensional scaling VIA an extended euclidean model 总被引:1,自引:0,他引:1
An Extended Two-Way Euclidean Multidimensional Scaling (MDS) model which assumes both common and specific dimensions is described and contrasted with the standard (Two-Way) MDS model. In this Extended Two-Way Euclidean model then stimuli (or other objects) are assumed to be characterized by coordinates onR common dimensions. In addition each stimulus is assumed to have a dimension (or dimensions) specific to it alone. The overall distance between objecti and objectj then is defined as the square root of the ordinary squared Euclidean distance plus terms denoting the specificity of each object. The specificity,s
j
, can be thought of as the sum of squares of coordinates on those dimensions specific to objecti, all of which have nonzero coordinatesonly for objecti. (In practice, we may think of there being just one such specific dimension for each object, as this situation is mathematically indistinguishable from the case in which there are more than one.)We further assume that
ij
=F(d
ij
) +e
ij
where
ij
is the proximity value (e.g., similarity or dissimilarity) of objectsi andj,d
ij
is the extended Euclidean distance defined above, whilee
ij
is an error term assumed i.i.d.N(0, 2).F is assumed either a linear function (in the metric case) or a monotone spline of specified form (in the quasi-nonmetric case). A numerical procedure alternating a modified Newton-Raphson algorithm with an algorithm for fitting an optimal monotone spline (or linear function) is used to secure maximum likelihood estimates of the paramstatistics) can be used to test hypotheses about the number of common dimensions, and/or the existence of specific (in addition toR common) dimensions.This approach is illustrated with applications to both artificial data and real data on judged similarity of nations. 相似文献
994.
Robert L. Beck 《Journal of Family Therapy》1989,11(3):231-241
This paper describes the use of concurrent individual and conjoint sessions in couples psychotherapy. The introduction of these individual interviews is seen as supporting the individual changes which must be made to effect change in the structure of the relationship. The benefits of this interventive scheme in dynamically oriented couples' treatment will be illustrated through the presentation of case examples. 相似文献
995.
I. Bennun 《Journal of Family Therapy》1989,11(3):243-255
Thirty-five families completed ratings describing their perceptions of their therapists. These ratings were then correlated with measures of outcome to assess whether there was a relationship between experiences of the therapist and treatment outcome. Further, the study addresses whether some family members' perceptions are more influential in affecting the course of treatment. The results showed that family members' perception of the therapist does have an impact on treatment outcome, but not all members affect the outcome equally. Further results and their implications are discussed. 相似文献
996.
Thomas C. Ryckman 《Synthese》1989,79(2):191-200
Examines the connections among believing, saying, and expressing in situations where the sentence used is a declarative sentence containing at least one proper name. Proposes a new way of understanding these connections. Develops an argument for the thesis that, although we typically believe the singular propositions expressed by our uses of name sentences, we rarely use such sentences because we believe those propositions. 相似文献
997.
998.
999.
Elizabeth F. Loftus Karen Donders Hunter G. Hoffman Jonathan W. Schooler 《Memory & cognition》1989,17(5):607-616
In two experiments involving a total of 542 subjects, a series of slides depicting a burglary was shown. After the initial event, subjects were exposed to one or more narratives about the event that contained some misinformation or neutral information about four critical details. Finally, subjects were tested on their memories of what they saw, and their reaction times and confidence levels were measured. When subjects took a standard test in which the misinformation item was a possible response option, they responded very quickly and confidently when making this incorrect choice. Misled subjects responded as quickly and confidently to these "unreal" memories as they did to their genuine memories. It does not seem, then, that the misinformation effect arises from a large proportion of subjects who must resolve a conflict between two memories when they are tested, a conflict that would be expected to take time. When subjects took a modified test in which the misinformation item was not a possible response, misled subjects were as accurate as were controls, but they responded more slowly, regardless of whether they ultimately chose the right or wrong option. These findings indicate that misinformation does introduce some form of interference not detected by a simple test of accuracy. 相似文献
1000.
In this study, we investigated bases for encoding linguistic stimuli in short-term memory. Past research has provided evidence for both phonological (sound-based) and cherological (sign-based) encoding, the former typically found with hearing subjects and the latter with deaf users of sign language. In the present experiment, encoding capabilities were delineated from encoding preferences, using 58 subjects comprising six groups differing in hearing ability and linguistic experience. Phonologically related, cherologically related, and control lists were presented orally, manually, or through both modalities simultaneously. Recall performance indicated that individuals encode flexibly, the code actually used being biased by incoming stimulus characteristics. Subjects with both sign and speech experience recalled simultaneous presentations better than ones presented orally or manually alone, which reveals the occurrence of enhanced encoding as a function of linguistic experience. Total linguistic experience appeared to determine recall accuracy following different types of encoding, rather than determining the encoding basis used. 相似文献