全文获取类型
收费全文 | 23919篇 |
免费 | 214篇 |
出版年
2023年 | 53篇 |
2022年 | 79篇 |
2021年 | 114篇 |
2020年 | 139篇 |
2019年 | 126篇 |
2018年 | 3630篇 |
2017年 | 2971篇 |
2016年 | 2381篇 |
2015年 | 301篇 |
2014年 | 210篇 |
2013年 | 574篇 |
2012年 | 844篇 |
2011年 | 2630篇 |
2010年 | 2667篇 |
2009年 | 1542篇 |
2008年 | 1918篇 |
2007年 | 2324篇 |
2006年 | 191篇 |
2005年 | 298篇 |
2004年 | 244篇 |
2003年 | 188篇 |
2002年 | 118篇 |
2001年 | 63篇 |
2000年 | 98篇 |
1999年 | 47篇 |
1998年 | 41篇 |
1997年 | 30篇 |
1996年 | 16篇 |
1995年 | 9篇 |
1994年 | 15篇 |
1993年 | 15篇 |
1992年 | 12篇 |
1991年 | 18篇 |
1990年 | 16篇 |
1989年 | 13篇 |
1988年 | 10篇 |
1987年 | 13篇 |
1986年 | 9篇 |
1985年 | 13篇 |
1984年 | 7篇 |
1981年 | 8篇 |
1979年 | 6篇 |
1975年 | 7篇 |
1973年 | 9篇 |
1972年 | 9篇 |
1971年 | 14篇 |
1969年 | 7篇 |
1968年 | 16篇 |
1966年 | 11篇 |
1965年 | 12篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
151.
The authors of this essay suggest that the field of bioethics and Christian theology have a great deal to offer to each other. The authors first argue that representatives from both fields must first make sure that they fully and correctly represent their respective position. In other words, scientists, ethicists, and theologians alike must make sure that they present their fields and not use their knowledge merely for personal gain at the stake of misguiding people. Once this is established, the authors then proceed to show the intimate relationship between Christianity and medicine that has existed throughout the ages. It is a call for a continuation of such a relationship that the authors suggest between bioethics and theology. Through an integration of bioethics and Christian theology, both scientists/physicians and theologians are able to gain greater insight into the human person—a focus in both fields. 相似文献
152.
Objectives: To understand the impact of physicians and patients religious/spiritual orientation on discussions of spiritual issues. Methods: We performed semi-structured interviews of 10 Missouri family physicians and 10 patients of these physicians, selecting subjects nonrandomly to represent a range of demographic factors, practice types, and chronic or terminal illness. We coded and evaluated transcribed interviews for themes. Results: Respondents expressed that similar belief systems facilitate patient–physician spiritual interactions and bring confidence to their relationships. Those holding dissimilar faiths noted limited ability to address spiritual questions directly. They cited significant barriers to spiritual interaction but considered that ecumenism, use of patient-centered care, and negotiation skills lessen these barriers. Conclusions: Our respondents view spirituality similarly to other aspects of the physician–patient relationship involving differing viewpoints. Where discordance exists, cross-cultural, patient-centered, diplomatic approaches facilitate spiritual discussions. 相似文献
153.
154.
Several researchers have suggested that conditioning history may have long-term effects on fixed-interval performances of rats. To test this idea and to identify possible factors involved in temporal control development, groups of rats initially were exposed to different reinforcement schedules: continuous, fixed-time, and random-interval. Afterwards, half of the rats in each group were studied on a fixed-interval 30-s schedule of reinforcement and the other half on a fixed-interval 90-s schedule of reinforcement. No evidence of long-term effects attributable to conditioning history on either response output or response patterning was found; history effects were transitory. Different tendencies in trajectory across sessions were observed for measures of early and late responding within the interreinforcer interval, suggesting that temporal control is the result of two separate processes: one involved in response output and the other in time allocation of responding and not responding. 相似文献
155.
Four experiments were designed to investigate whether the frequency of words used to create pseudowords plays an important role in lexical decision. Computational models of the lexical decision task (e.g., the dual route cascaded model and the multiple read-out model) predict that latencies to low-frequency pseudowords should be faster than latencies to high-frequency pseudowords. Consistent with this prediction, results showed that when the pseudowords were created by replacing one internal letter of the base word (Experiments 1 and 3), high-frequency pseudowords yielded slower latencies than low-frequency pseudowords. However, this effect occurred only in the leading edge of the response time (RT) distributions. When the pseudowords were created by transposing two adjacent internal letters (Experiment 2), high-frequency pseudowords produced slower latencies in the leading edge and in the bulk of the RT distributions. These results suggest that transposed-letter pseudowords may be more similar to their base words than replacement-letter pseudowords. Finally, when participants performed a go/no-go lexical decision task with one-letter different pseudowords (Experiment 4), high-frequency pseudowords yielded substantially faster latencies than low-frequency pseudowords, which suggests that the lexical entries of high-frequency words can be verified earlier than the lexical entries of low-frequency words. The implications of these results for models of word recognition and lexical decision are discussed. 相似文献
156.
Statistical learning is one of the key mechanisms available to human infants and adults when they face the problems of segmenting a speech stream (Saffran, Aslin, & Newport, 1996) and extracting long-distance regularities (G6mez, 2002; Pe?a, Bonatti, Nespor, & Mehler, 2002). In the present study, we explore statistical learning abilities in rats in the context of speech segmentation experiments. In a series of five experiments, we address whether rats can compute the necessary statistics to be able to segment synthesized speech streams and detect regularities associated with grammatical structures. Our results demonstrate that rats can segment the streams using the frequency of co-occurrence (not transitional probabilities, as human infants do) among items, showing that some basic statistical learning mechanism generalizes over nonprimate species. Nevertheless, rats did not differentiate among test items when the stream was organized over more complex regularities that involved nonadjacent elements and abstract grammar-like rules. 相似文献
157.
On March 11, 2004, Al-Qaeda set off 10 bombs on several train routes in Madrid. 192 people were killed and 2,000 wounded. In this study, 1,179 questionnaires were administered Week 2 after the attacks to residents 18 years and over from the affected geographical areas. The questionnaire included items about sociodemographic variables and exposure to the attacks. Psychological effects were assessed as presence of acute stress and depressive symptomatology and functional impairment. 46.7% of the sample presented symptomatology of acute stress and 49.6% depressive symptoms. Among the symptoms of acute stress, the most frequent were re-experiencing (72.5%) and dissociative symptoms (71.8%). The chief predicting variables in symptomatology were being female, over 65 yr. old, and a habitual train user. The large number of affected people was refined with an item analysis and the consideration of severity of interference in psychosocial functioning. 相似文献
158.
Amador-Campos JA Forns-Santacana M Martorell-Balanzó B Guàrdia-Olmos J Peró-Cebollero M 《Psychological reports》2005,97(3):847-860
Confirmatory factor analysis examined the factor structure of DSM IV Attention Deficit Hyperactivity Disorder symptoms and analyzed the differences in informants' ratings of ADHD symptoms by children's age and sex. A sample of 1,018 Spanish school children, 574 girls and 444 boys, ages 4 to 12 years, was rated by teachers and parents. Confirmatory factor analysis showed a similar fit for the three-factor model of Inattention, Hyperactivity, and Impulsivity (teachers: CFI = .976, RMR = .041, % of total variance = 83.2; parents: CFI = .969, RMR = .037, % of total variance = 82.7) and for the two-factor model of Inattention and Hyperactivity Impulsivity (teachers: CFI = .958, RMR = .044, % of total variance = 79.3; parents: CFI = .961, RMR = .038, % of total variance, 79.9). The two-factor model was selected as a parsi monious representation of the teachers' and parents' ratings of ADHD symptoms. Analyses of variance indicated significant differences in teachers' and parents' mean ratings across sex and school grades of children. 相似文献
159.
This study examined the dimensional structure of Tomás-Sábado and Gómez-Benito's Death Anxiety Inventory and Templer, et al.'s Death Depression Scale-Revised. The responses of 244 Spanish nurses to the Spanish forms of both scales were evaluated by means of a principal axis factor analysis with direct Oblimin rotation. Five significant factors were identified: Internally Generated Death Anxiety, Death Depression, Externally Generated Death Anxiety, Death Threat, and Death Sadness, accounting for 51.6% of the variance. The distribution of the factor loadings for the items of both scales on the five factors supported the discriminant validity of the constructs specific to each of the scales and justified their use in evaluating death anxiety and death depression independently. 相似文献
160.
In this paper we present the syntax and semantics of a temporal action language named Alan, which was designed to model interactive multimedia presentations where the Markov property does not always hold. In general,
Alan allows the specification of systems where the future state of the world depends not only on the current state, but also on
the past states of the world. To the best of our knowledge, Alan is the first action language which incorporates causality with temporal formulas. In the process of defining the effect of
actions we define the closure with respect to a path rather than to a state, and show that the non-Markovian model is an extension
of the traditional Markovian model. Finally, we establish relationship between theories of Alan and logic programs. 相似文献