全文获取类型
收费全文 | 32693篇 |
免费 | 1329篇 |
国内免费 | 8篇 |
专业分类
34030篇 |
出版年
2019年 | 428篇 |
2018年 | 559篇 |
2017年 | 586篇 |
2016年 | 584篇 |
2015年 | 418篇 |
2014年 | 529篇 |
2013年 | 2373篇 |
2012年 | 972篇 |
2011年 | 1038篇 |
2010年 | 609篇 |
2009年 | 606篇 |
2008年 | 897篇 |
2007年 | 878篇 |
2006年 | 830篇 |
2005年 | 746篇 |
2004年 | 729篇 |
2003年 | 658篇 |
2002年 | 692篇 |
2001年 | 1018篇 |
2000年 | 928篇 |
1999年 | 710篇 |
1998年 | 381篇 |
1997年 | 309篇 |
1996年 | 306篇 |
1992年 | 548篇 |
1991年 | 541篇 |
1990年 | 526篇 |
1989年 | 537篇 |
1988年 | 530篇 |
1987年 | 494篇 |
1986年 | 521篇 |
1985年 | 570篇 |
1984年 | 451篇 |
1983年 | 431篇 |
1982年 | 354篇 |
1981年 | 337篇 |
1979年 | 521篇 |
1978年 | 378篇 |
1977年 | 311篇 |
1976年 | 358篇 |
1975年 | 432篇 |
1974年 | 486篇 |
1973年 | 507篇 |
1972年 | 407篇 |
1971年 | 381篇 |
1970年 | 378篇 |
1969年 | 408篇 |
1968年 | 488篇 |
1967年 | 421篇 |
1966年 | 422篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
131.
132.
133.
134.
135.
136.
A E Puente 《Perceptual and motor skills》1988,66(2):639-642
MMPI profiles of 22 chronic arthritic patients were compared to 22 control pain (nonorganic) patients. While elevations were noted in the HS, D, and Hy scales for the rheumatoid patients, the over-all profiles differed from controls on the PA scale. 相似文献
137.
For 3 consecutive days cockroaches (Periplaneta americana) were exposed to either escapable, inescapable, or no shock in an escape task. Twenty-four hours later they were tested in a shuttlebox escape task. There were reliable differences between escapable and inescapable animals and between inescapable and control animals in both escape latencies and the number of failures to escape. 相似文献
138.
Previously we (Bruno & Cutting, 1988) explored the perception of spatial relations among objects laid out in a computer-generated environment. In his commentary on our article, Massaro (1988) raised several issues. The most important is from his reanalysis, which indicated that--because of a subadditive trend in the results--additive and multiplicative strategies fit our data in Experiment 1 about equally well. In reply, we performed a different analysis. Results corroborate subadditivity--and hence multiplicative information combination--in Experiment 1 but provide no evidence for it in Experiments 2 and 3. On the whole, then, the results still support additivity more strongly than any other combination rule and thus support our notion of minimodularity. 相似文献
139.
Fragile X speech phonology in Finnish 总被引:1,自引:0,他引:1
Fragile X syndrome is a recently discovered relatively common syndrome linked with an anomaly of the X chromosome and causing handicaps of cognitive development especially in males. In the present phonological analysis we will discuss the sound patterns of two Finnish fragile X speakers, a five (borderline intelligence)- and an eight (mildly mentally retarded)-year-old boy. The fragile X syndrome is not necessarily linked with any anomalies of speech organs. The subjects could produce all Finnish speech sounds in isolated test words. However, in the present samples of connected speech they exhibited general dysphonology. What is noteworthy is that their phonological error patterns resembled each other to a great extent. Among the common features were the tendencies to substitute and omit phonemes. As for vowels, our results showed about one-half of the errors to be omissions. Labiality and quantity oppositions were quite resistant to substitution. Most substitution errors of place of consonants occurred in dentals. As for the feature of manner, /r/ and /s/ were the phonemes most prone for substitution. A tendency toward spirantization or /h/ sation was common for both patients. The number of additions was clearly lower than has been reported for English-speaking developmentally dyspraxic children and also for Finnish Broca's aphasics. The speech problems of our patients seemed to indicate higher level motor encoding problems of linguistic information rather than peripheral articulatory deficits. 相似文献
140.
Scopolamine interactions with D1 and D2 antagonists on radial-arm maze performance in rats 总被引:1,自引:0,他引:1
E D Levin 《Behavioral and neural biology》1988,50(2):240-245
Recent evidence indicates that acetylcholine and dopamine play complementary roles in cognitive as well as motor functions. In our previous study, the dopamine receptor blocker, haloperidol, was found to attenuate the radial-arm maze choice accuracy deficit caused by the muscarinic acetylcholine receptor blocker, scopolamine. Haloperidol has activity in blocking both D1 and D2 dopamine receptor subtypes. The current study was conducted to determine whether this dopamine-acetylcholine interaction specifically involved D1 or D2 dopamine receptors. The D1 antagonist, SCH 23390, and the D2 antagonist, raclopride, were administered with a dose of scopolamine which caused choice accuracy deficits in the radial-arm maze. The scopolamine-induced deficit was reversed by SCH 23390, the D1 antagonist, indicating that D1 blockade alone is sufficient to reverse the amnestic effects of muscarinic blockade. There was no indication in this study that the D2 blocker, raclopride, had a similar effect. However, this does not mean that such an effect may not be present at other doses of raclopride or with other D2 antagonists. The present finding that D1 blockade counteracts scopolamine-induced cognitive dysfunction not only furthers the understanding of dopamine-acetylcholine relationships in cognitive function, it also suggests a promising direction for the development of treatments for cognitive dysfunction due to cholinergic loss. 相似文献