全文获取类型
收费全文 | 25029篇 |
免费 | 1109篇 |
国内免费 | 16篇 |
专业分类
26154篇 |
出版年
2020年 | 323篇 |
2019年 | 376篇 |
2018年 | 512篇 |
2017年 | 538篇 |
2016年 | 579篇 |
2015年 | 435篇 |
2014年 | 504篇 |
2013年 | 2209篇 |
2012年 | 883篇 |
2011年 | 944篇 |
2010年 | 593篇 |
2009年 | 556篇 |
2008年 | 761篇 |
2007年 | 734篇 |
2006年 | 661篇 |
2005年 | 582篇 |
2004年 | 594篇 |
2003年 | 556篇 |
2002年 | 602篇 |
2001年 | 800篇 |
2000年 | 796篇 |
1999年 | 589篇 |
1998年 | 315篇 |
1997年 | 296篇 |
1996年 | 249篇 |
1995年 | 264篇 |
1994年 | 226篇 |
1993年 | 235篇 |
1992年 | 464篇 |
1991年 | 421篇 |
1990年 | 433篇 |
1989年 | 416篇 |
1988年 | 385篇 |
1987年 | 354篇 |
1986年 | 377篇 |
1985年 | 382篇 |
1984年 | 340篇 |
1983年 | 322篇 |
1982年 | 232篇 |
1981年 | 269篇 |
1979年 | 306篇 |
1978年 | 280篇 |
1977年 | 244篇 |
1976年 | 227篇 |
1975年 | 290篇 |
1974年 | 344篇 |
1973年 | 263篇 |
1972年 | 266篇 |
1969年 | 252篇 |
1968年 | 248篇 |
排序方式: 共有10000条查询结果,搜索用时 8 毫秒
951.
R. A. Kinchla Victor Solis-Macias James Hoffman 《Attention, perception & psychophysics》1983,33(1):1-10
Two experiments are reported in which observers had to utilize information from one of two structural levels of visual stimulus patterns (large letters composed of smaller ones). They could utilize information more rapidly form one level only at the cost of slower utilization from the other. This trade off defines an empirical attention operating characteristic (AOC) which is consistent with a simple mathematical model of the perceptual process: when viewing a stimulus, the observer selects one of two alternative “attentional” strategies, where each strategy is optimal for utilizing information from one structural level, but less than optimal for the other. 相似文献
952.
Glutamate is believed to be quantitatively the most outstanding of the excitatory transmitters in the CNS. Certain conformationally related analogues, e. g. kainate, N-methyl-D-aspartate, ibotenate, and homocysteate, act as glutamate agonists. The local or systemic administration of these "excitotoxic" compounds induces epileptiform activity pointing out new and deeper insights into the epileptic process. Additionally, the glutamate transmitter hypothesis is expected to give a chance of a causal comprehension for choreatic processes as well as for the mode of action of anticonvulsant and antispastic agents. 相似文献
953.
K P Müller 《Psychiatrie, Neurologie, und medizinische Psychologie》1983,35(4):244-251
Two simple sociometric techniques for practical use are described which are derived from the data given in the sociogram. Compared with the conventional sociogram, the group rank score we use everyday therapy has the advantage that it can be published. It permits members of the group to better identify the social situations which cause specific psychic impulses. The sociogram is reserved for the therapist. In our opinion the sociodynamogram has certain advantages over both methods because it provides an insight into spheres which are inaccessible in the sociogram and group rank score. 相似文献
954.
Quantitative amino acid determination in the serum and cerebrospinal fluid in endogenous depressions
B Dreves P Wiechert K Ernst 《Psychiatrie, Neurologie, und medizinische Psychologie》1983,35(7):409-415
The levels of 20 amino acids were measured in the plasma and cerbrospinal fluid of 41 patients with endogenic depressions. The plasma levels of 12 amino acids were found to be significantly lower in the patients than in the control group, but cerebrospinal fluid levels were significantly lower only in the case of taurine, glutamine, phenylalanine and aginine. Comparison of the same amino acid levels in treated and non-treated patients showed that serine and alpha-aminobutyric acid serum concentrations were higher in the nontreated patients. The tyrosine and phenylalanine levels in the cerebrospinal fluid of the patients who had received medicamentous treatment were higher than in the other group. 相似文献
955.
956.
Latent trait models for binary responses to a set of test items are considered from the point of view of estimating latent trait parameters=(
1, ,
n
) and item parameters=(
1, ,
k
), where
j
may be vector valued. With considered a random sample from a prior distribution with parameter, the estimation of (, ) is studied under the theory of the EM algorithm. An example and computational details are presented for the Rasch model.This work was supported by Contract No. N00014-81-K-0265, Modification No. P00002, from Personnel and Training Research Programs, Psychological Sciences Division, Office of Naval Research. The authors wish to thank an anonymous reviewer for several valuable suggestions. 相似文献
957.
958.
Subjects viewed sequences of slides depicting everyday events, and in later recognition tests, they correctly rejected distractors that were inconsistent with some invariant of the event but falsely accepted consistent distractors. J. J. Jenkins has accounted for the differential recognition of consistent and inconsistent slides of pictorial sequences in terms of fusion, the abstraction of an event from a series of temporally related items. The conditions under which event fusion was likely to occur were manipulated in three experiments: degree of ordering of the action-sequence slides, semantic vs. nonsemantic orienting tasks during acquisition, and duration of retention interval Recognition performance was generally more accurate under conditions of semantic processing, ordered acquisition sequences (for the semantic task), and shorter retention intervals. However, these variables did not affect differential recognition of consistent vs. inconsistent slides. A further experiment showed that the absence of an effect of disordering acquisition sequences on differential recognition could not be attributed to subjects’ reordering the disordered sequences in a way consistent with the original event. The data did not support the hypothesis that recognition performance was based on fusion of events depicted by temporally ordered slide sequences. It was suggested that memory for featural detail is a relevant factor in performance. 相似文献
959.
Kenneth J. Zucker Jo -Anne K. Finegan Robert W. Doering Susan J. Bradley 《Journal of abnormal child psychology》1983,11(2):287-298
The Draw-a-Person test was used to evaluate a number of questions regarding children referred for potential problems in their gender-identity development (N = 36). Sibling (N = 31), psychiatric (N = 23), and normal (N = 30) children served as comparison groups. The major results included the following: (1) The gender-referred children were more likely to draw an opposite-sex person when requested to "draw a person" than were the other three groups; (2) the gender-referred children who drew an opposite-sex person were more likely to play with opposite-sex toys and dress-up apparel on a free-play task than were the gender-referred children who drew a same-sex person; (3) the gender-referred children drew taller opposite-sex persons than same-sex persons; (4) using Koppitz's (1968) criteria, the normal children had a smaller proportion of emotional disturbance indicators in their same-sex drawings than did the other three groups. These findings were discussed with regard to psychometric and interpretive issues in the assessment of children with atypical gender-role behavior. 相似文献
960.
Speech-language clinicians working with the confirmed stuttering client are often faced with the clinical management of the covert symptoms of stuttering in addition to the more observable and measurable overt symptoms. The authors report the successful use of awareness techniques to exaggerate the subjective experience of these covert symptoms and encourage the use of these techniques as an adjunct to the counseling and desensitization procedures traditionally employed. A transcribed clinical management session in which several awareness techniques are used to aid the client in an introspective examination of “anticipation of stuttering,” is analyzed in order to reach some specific recommendations for using awareness techniques in the clinical management of the covert symptoms of stuttering. 相似文献