全文获取类型
收费全文 | 1978篇 |
免费 | 133篇 |
国内免费 | 1篇 |
专业分类
2112篇 |
出版年
2021年 | 32篇 |
2020年 | 42篇 |
2019年 | 46篇 |
2018年 | 67篇 |
2017年 | 84篇 |
2016年 | 76篇 |
2015年 | 56篇 |
2014年 | 76篇 |
2013年 | 215篇 |
2012年 | 93篇 |
2011年 | 98篇 |
2010年 | 67篇 |
2009年 | 63篇 |
2008年 | 80篇 |
2007年 | 66篇 |
2006年 | 54篇 |
2005年 | 65篇 |
2004年 | 56篇 |
2003年 | 39篇 |
2002年 | 64篇 |
2001年 | 31篇 |
2000年 | 35篇 |
1999年 | 26篇 |
1998年 | 18篇 |
1997年 | 17篇 |
1996年 | 15篇 |
1995年 | 15篇 |
1994年 | 16篇 |
1993年 | 15篇 |
1992年 | 22篇 |
1991年 | 16篇 |
1990年 | 15篇 |
1989年 | 19篇 |
1988年 | 16篇 |
1987年 | 16篇 |
1985年 | 24篇 |
1984年 | 23篇 |
1983年 | 15篇 |
1981年 | 18篇 |
1980年 | 19篇 |
1979年 | 16篇 |
1978年 | 17篇 |
1977年 | 22篇 |
1976年 | 17篇 |
1975年 | 21篇 |
1973年 | 16篇 |
1971年 | 13篇 |
1970年 | 13篇 |
1968年 | 18篇 |
1967年 | 18篇 |
排序方式: 共有2112条查询结果,搜索用时 0 毫秒
71.
Effects of naloxone on acquisition of autoshaped behavior were investigated. Rats deprived to 85% of free-feeding weights were trained to touch a retractable lever; delivery of a food pellet occurred on every trial following lever retraction. The lever was retracted immediately if a touch occurred within 15 s, or automatically after 15 s. Analyses were conducted on number and latencies of touches of the extended lever, nose-pokes (touches) directed at the retracted lever during intertrial intervals (a measure less constrained by ceiling effects than extended lever touches), and unconditioned exploratory rearing activity, measured as touches of a metal strip mounted above the grid floor of the apparatus. In an initial experiment, male Sprague-Dawley rats were given saline or naloxone (2.0 mg/kg, ip) 5 min before a training session of 12 trials. Two days later they were tested, in the absence of drug, in a session of 36 (three blocks of 12) trials. Naloxone depressed training levels of lever responding, in addition to slowing acquisition rate. No effect of naloxone was observed on rearing activity. Previous work showed that injection of saline 5 min before behavioral testing increases the rate of autoshaping compared to injections 30 min before (Messing & Sparber, 1984). Thus, effects of naloxone on acquisition of lever-directed behaviors may have been confounded by behavioral depressant effects and/or by an injection effect such a short time before testing. In a second experiment naloxone (0.5 or 2.0 mg/kg) was injected after five of seven training sessions (12 trials each) to male and female rats. A 6-s delay of reinforcement was inserted between lever retraction and food delivery, slowing acquisition rates and providing the opportunity to test the effects of naloxone throughout a multiple-session task. The low dose retarded acquisition of extended lever touching in both sexes; both doses retarded acquisition of interim lever touching in males. Thus, in some circumstances, post-training naloxone administration may impair learning. The results support the notion that low doses of naloxone may have agonist activity. 相似文献
72.
73.
Ben Quash 《Modern Theology》2018,34(2):258-266
74.
Well-known literature reviews from the 1960s question whether cognitive dissonance underlies experimental participants' selective exposure of themselves to consonant messages and avoidance of dissonant ones. A meta-analytic review of 16 studies published from 1956 to 1996 and involving 1,922 total participants shows that experimental tests consistently support the supposition that dissonance is associated with selective exposure (r = .22, p < .001). Statistical power exceeded .99. Advances in statistical methodology and increased attention to selecting appropriate tests of dissonance theory were essential to finally resolving this question. 相似文献
75.
At the segmental level, the rate of speaking affects the degree of physical undershoot of articulatory targets and the resulting perception. Little is known regarding evidence of these effects at the suprasegmental level, particularly in intonation. In this study, the effect of rate of speaking on fundamental frequency and on perceptual judgments of peak pitch in a rise-fall intonation pattern was investigated. First, speakers produced rise-fall intonations in sentence contexts at slow, normal, and fast speaking rates. Peak fundamental frequencies (F0) of the slow productions were significantly lower than those of the normal or fast productions. The mean normal rate production of the word Miami was used as a model for the target word in a series of subsequent perceptual experiments. Altering the duration of the target word to represent slow, normal, and fast rates of speaking did not affect listener judgment of peak pitch. Finally, the pitch of the target word was measured in a sentence context. No differences between peak pitch in isolation or in sentence context were found. It was concluded that the production and perception of this form of intonation was not subject to the effects of rate that are seen at the segmental level. 相似文献
76.
Specificity of the MMPI-2 Fake Bad Scale as a marker for personal injury malingering 总被引:1,自引:0,他引:1
Psychologists who evaluate patients in medicolegal contexts should utilize objective assessment data with empirically established sensitivity and specificity for identifying negative response bias. The purpose of this study was to investigate the specificity of the Fake Bad Scale for identifying negative response bias in personal injury claimants. The cutoff scores proposed by Lees-Haley and colleagues were applied a federal prison, medical outpatients, and patients from to inmate volunteers from substance abuse unit. Half of the inmates were given instructions to malinger psychopathology to affect the adjudication process, and the remaining inmates and all of the hospital patients were given standard instructions. The original cutoff scores correctly identified the majority of inmates instructed to malinger psychopathology, but these scores resulted in unacceptably high rates of false positive classifications. The revised cutoff scores resulted in fewer false positives, i.e., 8%-24%. 相似文献
77.
Oliver AL 《Psychoanalytic review》2002,89(5):665-680
78.
Pigeons were trained on a multiple schedule in which separate concurrent schedules were presented in the two components of the schedule. During one component, concurrent variable-interval 40-sec variable-interval 80-sec schedules operated. In the second component, concurrent variable-interval 40-sec variable-interval 20-sec schedules operated. After stable baseline performance was obtained in both components, extinction probe choice tests were presented to assess preference between the variable-interval 40-sec schedules from the two components. The variable-interval 40-sec schedule paired with the variable-interval 80-sec schedule was preferred over the variable-interval 40-sec schedule paired with the variable-interval 20-sec schedule. The subjects were also exposed to several resistance-to-change manipulations: (1) prefeeding prior to the experimental session, (2) a free-food schedule added to timeout periods separating components, and (3) extinction. The results indicated that preference and resistance to change do not necessarily covary. 相似文献
79.
Korcz KA 《Journal of social philosophy》2002,33(4):581-605
80.
Previous studies have found that priming a target like cerr-o ("hill") with an unmasked stem-homograph (e.g., cerr-ar, "to close") or with an unmasked allomorph of a stem-homograph (e.g., cierr-a, "he/she/it closes") has an inhibitory effect on target recognition. We report evidence from stem-homograph priming studies that implicate both morphological parsing and lexical selection processes at the lemma level. We argue that stem-homograph inhibition is the product of lexical selection mechanisms that are engaged just when a fully ambiguous stimulus (here, an inflectional stem) must be assigned one of its viable interpretations in order to afford conscious perception of lexical identity. 相似文献