全文获取类型
收费全文 | 6135篇 |
免费 | 142篇 |
国内免费 | 29篇 |
专业分类
6306篇 |
出版年
2012年 | 610篇 |
2011年 | 715篇 |
2010年 | 169篇 |
2009年 | 74篇 |
2008年 | 538篇 |
2007年 | 590篇 |
2006年 | 484篇 |
2005年 | 426篇 |
2004年 | 407篇 |
2003年 | 398篇 |
2002年 | 339篇 |
2001年 | 226篇 |
2000年 | 290篇 |
1999年 | 136篇 |
1998年 | 39篇 |
1997年 | 30篇 |
1996年 | 25篇 |
1995年 | 23篇 |
1994年 | 17篇 |
1993年 | 17篇 |
1992年 | 26篇 |
1991年 | 25篇 |
1990年 | 19篇 |
1989年 | 15篇 |
1988年 | 13篇 |
1987年 | 21篇 |
1985年 | 17篇 |
1984年 | 19篇 |
1983年 | 29篇 |
1982年 | 25篇 |
1981年 | 15篇 |
1980年 | 13篇 |
1979年 | 12篇 |
1978年 | 15篇 |
1976年 | 18篇 |
1973年 | 8篇 |
1965年 | 14篇 |
1963年 | 10篇 |
1959年 | 17篇 |
1958年 | 51篇 |
1957年 | 43篇 |
1956年 | 46篇 |
1955年 | 37篇 |
1954年 | 34篇 |
1953年 | 28篇 |
1952年 | 27篇 |
1951年 | 27篇 |
1950年 | 24篇 |
1949年 | 14篇 |
1948年 | 12篇 |
排序方式: 共有6306条查询结果,搜索用时 15 毫秒
51.
Previous research has shown that in a three-term spatial reasoning task, the second premise of a German premise pair is especially easy to comprehend if (1) the prepositional object rather than the grammatical subject denotes the given entity, and if (2) the term denoting the given entity precedes the term denoting the new entity. Accordingly, the second premise is easiest to comprehend with noncanonical word order--that is, with the prepositional object in preverbal position denoting the given entity (e.g., To the right of the given object is the new subject). This finding is explained in terms of contextual licensing of noncanonical word order. Here, we discuss and tested two alternative accounts of contextual licensing, given-new and partially ordered set relations (Poset). The given-new account claims that noncanonical word order is licensed by the term denoting the given entity preceding the term denoting the new entity. On the Poset account, noncanonical word order is licensed if the preverbal constituent introduces a new entity that stands in a transitive, irreflexive, and asymmetric relation to a given entity. Comprehension times for second premises with spatial adverbs in four different word orders support both accounts of contextual licensing; Poset licensing was stronger than given-new licensing. 相似文献
52.
Weekes N Lewis R Patel F Garrison-Jakel J Berger DE Lupien SJ 《Stress (Amsterdam, Netherlands)》2006,9(4):199-206
The purpose of the present study was to investigate basic methodological issues related to the usage of an examination stress protocol in studies of psychoneuroendocrinology. In the present study, 57 undergraduate students served as participants. All subjects provided salivary samples and completed psychological inventories during a low examination stress period and again during a high examination stress period. Salivary samples were analyzed for cortisol. Three major findings were observed. First, the examination stress protocol proved to be an effective trigger of elevations in both psychological measures of stress and in cortisol levels. Second, sex differences were observed in cortisol levels, such that males showed an elevation in cortisol during the high examination stress session whereas females did not. Finally, no significant correlations were observed between elevations in psychological measures of stress and elevations in cortisol levels. These findings suggest that the examination stress protocol used in the present study effectively elevated both psychological stress and cortisol levels. Furthermore, these findings suggest that there are biological differences in how males and females respond to stress. Finally, no evidence was found to suggest a relationship between psychological and hormonal levels of stress. Together, these findings suggest the need to better define and consider the implications of both the specific measures of stress being used and individual differences in the subject samples in psychoendocrine studies. 相似文献
53.
Rasch analysis was used to illustrate the usefulness of item-level analyses for evaluating a common therapy outcome measure of general clinical distress, the Symptom Checklist-90-Revised (SCL-90-R; Derogatis, 1994). Using complementary therapy research samples, the instrument's 5-point rating scale was found to exceed clients' ability to make reliable discriminations and could be improved by collapsing it into a 3-point version (combining scale points 1 with 2 and 3 with 4). This revision, in addition to removing 3 misfitting items, increased person separation from 4.90 to 5.07 and item separation from 7.76 to 8.52 (resulting in alphas of .96 and .99, respectively). Some SCL-90-R subscales had low internal consistency reliabilities; SCL-90-R items can be used to define one factor of general clinical distress that is generally stable across both samples, with two small residual factors. 相似文献
54.
The medical humanities are often implemented in the undergraduate medicine curriculum through injection of discrete option courses as compensation for an overdose of science. The medical humanities may be reformulated as process and perspective, rather than content, where the curriculum is viewed as an aesthetic text and learning as aesthetic and ethical identity formation. This article suggests that a "humanities" perspective may be inherent to the life sciences required for study of medicine. The medical humanities emerge as a revelation of value inherent to an aesthetic medicine taught and learned imaginatively. 相似文献
55.
The authors examined measurement bias in the Hogan Personality Inventory by investigating differential item functioning (DIF) across sex and two racial groups (Caucasian and Black). The sample consisted of 1,579 Caucasians (1,023 men, 556 women) and 523 Blacks (321 men, 202 women) who were applying for entry-level, unskilled jobs in factories. Although the group mean differences were trivial, more than a third of the items showed DIF by sex (38.4%) and by race (37.3%). A content analysis of potentially biased items indicated that the themes of items displaying DIF were slightly more cohesive for sex than for race. The authors discuss possible explanations for differing clustering tendencies of items displaying DIF and some practical and theoretical implications of DIF in the development and interpretation of personality inventories. 相似文献
56.
Confidence intervals (CIs) give information about replication, but many researchers have misconceptions about this information. One problem is that the percentage of future replication means captured by a particular CI varies markedly, depending on where in relation to the population mean that CI falls. The authors investigated the distribution of this percentage for varsigma known and unknown, for various sample sizes, and for robust CIs. The distribution has strong negative skew: Most 95% CIs will capture around 90% or more of replication means, but some will capture a much lower proportion. On average, a 95% CI will include just 83.4% of future replication means. The authors present figures designed to assist understanding of what CIs say about replication, and they also extend the discussion to explain how p values give information about replication. 相似文献
57.
Tibbits D Ellis G Piramelli C Luskin F Lukman R 《The journal of pastoral care & counseling : JPCC》2006,60(1-2):27-34
The objective of this study was to determine if patients with diagnosed stage-1 hypertension could benefit by a forgiveness training program to achieve measurable reductions in anger expression and blood pressure. Twenty-five participants were randomly divided into wait-listed control and intervention groups. The control group monitored blood pressure while the intervention group participated in an 8-week forgiveness training program. At the end of eight weeks, the wait listed group became an intervention group. Those who received forgiveness training achieved significant reductions in anger expression when compared to the control group. While reductions in blood pressure were not achieved by all the participants, those participants who entered the program with elevated anger expression scores did achieve significant reductions in blood pressure. It is suggested that forgiveness training may be an effective clinical intervention for some hypertensive patients with elevated levels of anger. 相似文献
58.
59.
The effects of aging on performance were examined in signal detection, letter discrimination, brightness discrimination, and
recognition memory, with each subject tested on all four tasks. Ratcliff’s (1978) diffusion model was fit to the data for
each subject for each task, and it provided a good account of accuracy and the distributions of correct and error response
times. The model’s analysis of the components of processing showed that aging had three main effects: The nondecision components
of processing were slower and the decision criteria were more conservative for 60- to 74-year-old and 75- to 85-year-old subjects
than for college students, but the quality of the evidence on which decisions were based was as good for the older subjects
as for college students on some of the tasks. Individual differences among subjects in components of processing tended to
be preserved across the tasks, as was shown by strong correlations across the tasks in the parameters of the model that represent
the components of processing. For example, if the evidence on which a subject’s decisions were based was good in one task,
it tended to be good in all four tasks. 相似文献
60.
Cytotoxic lesions of the hippocampus do not impair social recognition memory in socially housed rats
Socially housed mice with cytotoxic lesions of the hippocampus do not exhibit social recognition memory 30 min following exposure to a juvenile mouse, however the social recognition memory of singly housed rats is unimpaired. The present study tests the hypothesis that social housing of rats could render social recognition memory hippocampally dependent as seen for mice. Rats were housed with juveniles or with adults. Two social recognition one-animal tests paralleling those used with mice were carried out. Seven social discrimination two-animal tests were also given. Sham operated and hippocampally lesioned rats had normal social memory at 30 min whether socially housed for 24, 48 h, 7 or 8 days prior to testing. These findings support other results indicating the hippocampus proper is not required for normal social memory in rats. In a final experiment, rats socially housed in groups of three since weaning, were tested for 30 min and 24 h social memory. Unlike mice, rats socially housed throughout life exhibited social memory only at 30 min, but not at 24 h. Manipulations that extend social memory in rats may be required to render social memory hippocampally dependent or rats and mice may differ in the neural mediation of social memory. 相似文献