全文获取类型
收费全文 | 57203篇 |
免费 | 2357篇 |
国内免费 | 21篇 |
专业分类
59581篇 |
出版年
2020年 | 533篇 |
2019年 | 645篇 |
2018年 | 910篇 |
2017年 | 944篇 |
2016年 | 1019篇 |
2015年 | 772篇 |
2014年 | 872篇 |
2013年 | 4174篇 |
2012年 | 1634篇 |
2011年 | 1613篇 |
2010年 | 1004篇 |
2009年 | 963篇 |
2008年 | 1399篇 |
2007年 | 1443篇 |
2006年 | 1228篇 |
2005年 | 1178篇 |
2004年 | 1103篇 |
2003年 | 1044篇 |
2002年 | 1083篇 |
2001年 | 1853篇 |
2000年 | 1771篇 |
1999年 | 1324篇 |
1998年 | 586篇 |
1996年 | 535篇 |
1992年 | 1213篇 |
1991年 | 1147篇 |
1990年 | 1175篇 |
1989年 | 1026篇 |
1988年 | 1035篇 |
1987年 | 976篇 |
1986年 | 1028篇 |
1985年 | 1105篇 |
1984年 | 845篇 |
1983年 | 773篇 |
1982年 | 543篇 |
1981年 | 534篇 |
1979年 | 967篇 |
1978年 | 659篇 |
1977年 | 605篇 |
1976年 | 585篇 |
1975年 | 821篇 |
1974年 | 961篇 |
1973年 | 1014篇 |
1972年 | 848篇 |
1971年 | 802篇 |
1970年 | 796篇 |
1969年 | 757篇 |
1968年 | 1011篇 |
1967年 | 884篇 |
1966年 | 790篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
221.
222.
223.
Ratings of pre-morbid intelligence level, derived from the hospital charts of 26 chronic schizophrenics, were correlated with the post-mortem brain volume measures of cortex, white matter, central grey matter, and ventricles. Contrary to hypothesis, no significant correlations were found. 相似文献
224.
LISE M. SAARI TERRY R. JOHNSON STEVEN D. MCLAUGHLIN DENISE M. ZIMMERLE 《Personnel Psychology》1988,41(4):731-743
A survey was systematically developed to assess issues related to management training and education, and it was sent to 1,000 randomly selected U.S. companies with at least 1,000 employees. Based on a 61% response rate, findings were obtained regarding issues such as needs assessment, management training and development approaches, reasons for selecting particular programs, characteristics of participants, how decisions are made regarding who will participate, preparation and follow-up of participants, evaluation of management training programs, future management training trends, and needed training content. Significant findings by company size and industry type also are reported. 相似文献
225.
Under simple- and choice-RT conditions, the biceps brachii muscle was examined in 8 healthy male subjects to determine how the temporal and spatial characteristics of elbow flexion and forearm supination differed at the initial phase of EMG activity and whether preparation or the presence of response uncertainty influenced the EMG outputs of the two movements. In the simple-RT condition, RT of supination was significantly faster than that of flexion but EMG activity of supination was less than that of flexion. In contrast, in the choice-RT condition, RT of flexion was significantly faster than that of supination but EMG activity of flexion was significantly reduced compared to supination. These findings indicate that advanced preparation or motor set facilitates the differentiation of RTs and EMG activities of the response movements and that response uncertainty causes a significant change in the temporal and spatial specificity of both elbow flexion and forearm supination. 相似文献
226.
227.
M R Lamb 《Journal of experimental psychology. Animal behavior processes》1988,14(1):96-104
Pigeons in a matching-to-sample experiment received (a) element samples (one of two colors or vertical or horizontal white lines), (b) separated compound samples (a color and a line element presented together), and (c) unified compound samples (vertical or horizontal colored lines). In Phase I, test stimuli were the two elements from one dimension; the dimension tested varied randomly when the sample was a compound. Element samples were matched better than unified samples, which were matched better than separated samples. In Phase II, two samples preceded the tests. On EC trials, the first sample (S1) was an element, and the second sample (S2) was a compound; on CE trials this order was reversed. One element of the compound sample was always the one appearing as the element sample on that trial (e.g., S1 = red, S2 = red-vertical). This element also served as the correct test alternative (e.g., test = red+ vs. green) except on probe trials when the correct test was the other element appearing in the compound (e.g., test = vertical+ vs. horizontal). Accuracy varied as a function of sample sequence when the compound was separated (EC greater than CE on nonprobe trials and CE greater than EC on prove trials). This pattern was not observed when the compound was unified. The data suggest that the element in EC trials served as a cue that increased processing of the cued dimension and decreased processing of the noncued dimension of separated compounds. However, both dimensions of unified compounds seem to have been processed regardless of cuing.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
228.
Targets related to ambiguous primes were projected to the left and right visual fields in a lexical priming experiment with stimulus onset asynchronies (SOA) of 35 and 750 msec. Right visual field results were similar to our earlier results with central projection (G. B. Simpson & C. Burgess, 1985, Journal of Experimental Psychology: Human Perception and Performance, 11, 28-39). Facilitation was found for the more frequent meaning at both SOAs and a decrease in facilitation for the less frequent meaning at the longer SOA. In contrast, left visual field results indicated a decay of facilitation for the more frequent meaning at the longer SOA, while activation for the subordinate meaning increased. Results suggest that, while automatic processing occurs in both hemispheres, only the left hemisphere engages in controlled processing of ambiguous word meanings. In addition, the present results support the idea that the right hemisphere has a special role in ambiguity resolution and that the right hemisphere lexicon possesses a richer endowment than earlier thought. 相似文献
229.
Fighting pairs of isolated DBA/2 mice showed a significant increase in tail-flick response latencies independent of whether opponents were losing or winning the combat. The effect lasted less than 10 min in both animals. Elevated pain thresholds were also found in isolates that attacked a nonaggressive conspecific, and were prevented by naltrexone (0.2 mg/kg), while a larger dose (1.0 mg/kg) inhibited the attack behavior. A small increase in pain threshold was observed after exposure of isolates to the test box alone, while isolation per se had no effect on baseline tail-flick latencies. The data demonstrate that endogenous pain suppressing systems are activated during attack and suggest that this opioid-mediated antinociception is a correlate of the isolation syndrome, reflecting enhanced arousal of the attacking animal. 相似文献
230.
M R D'Amato M Colombo 《Journal of experimental psychology. Animal behavior processes》1988,14(2):131-139
Cebus monkeys were trained on a five-item serial learning task, symbolized as ABCDE; the initial stages of training were on the shorter subseries AB, ABC, and ABCD. To assess the monkeys' knowledge of the sequential position of each item, pair-wise tests were given to 2 subjects after acquisition of the ABCD series and to 4 subjects after reaching criterion on the ABCDE series. In both tests, the monkeys performed at high levels on the interior pairs, which were BC for the ABCD series, and BC, BD, and CD for the ABCDE series. These results, as well as the orderly relations observed in the pair-wise tests between first-item response latency and first-item position and between second-item response latency and number of missing items, indicated that the monkeys had developed a well-organized internal representation of the four- and five-item series. Although pigeons are also capable of learning four-item and five-item series, they apparently do not develop a comparable representational structure. The disparity between the monkeys' and pigeons' representational competence for serial order is predictable from the difference in their capacities for associative transitivity. 相似文献