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931.
Competition and cooperation in the five-factor model: individual differences in achievement orientation 总被引:2,自引:0,他引:2
The authors investigated the relationship between basic achievement orientations of competition and cooperation and the five-factor model of personality as measured by the Revised NEO Personality Inventory (NEO-PI-R; P. T. Costa & R. R. McCrae, 1992). They examined 2 types of competition: hypercompetition (R. M. Ryckman, B. Thornton, & J. C. Butler, 1994) and personal development competition (R. M. Ryckman, M. Hammer, L. M. Kaczor, & J. A. Gold, 1996), as conceptualized by K. Horney (1937). In a sample of 251 young adults, 14% to 38% of the variance in achievement orientations was collectively predicted by NEO-PI-R domain scales. Of NEO-PI-R predictors, Agreeableness was most important in characterizing differences between various achievement orientations; Agreeableness was negatively related to hypercompetition, positively related to cooperation, and unrelated to personal development competition. Extraversion was positively related to both cooperation and personal development competition but was unrelated to hypercompetition. In contrast, Openness and Conscientiousness were least helpful in differentiating among achievement orientations. These findings support the useful application of the NEO-PI-R in achievement research and highlight competition and cooperation as interpersonally laden achievement orientations. 相似文献
932.
Two experiments were conducted to explore the potential effects of aging upon the perception and discrimination of speed. In the first experiment, speed difference thresholds were obtained for younger and older observers for a variety of standard speeds ranging from slow to fast. The second experiment was designed to evaluate the observers' ability to discriminate differences in the speed of moving patterns in the presence of significant amounts of noise (the noise was manipulated by limiting the lifetimes of individual moving stimulus elements). The results of both experiments revealed a significant deterioration in the ability of the older observers to perceive or detect differences in speed. While the presence of noise was found to affect the observers' discrimination performance, it affected both younger and older observers' thresholds in a proportionally equivalent manner-the older observers were no more affected by noise than the younger observers. 相似文献
933.
Observations made during two partial eclipses of the Sun show that the Mach bands on shadows cast by the Sun disappear and reappear asymmetrically as an eclipse progresses. These changes can be explained as due to changes in the shape of the penumbras of shadows as the visible portion of the Sun forms crescents of different orientation. 相似文献
934.
Hopkins WD Stoinski TS Lukas KE Ross SR Wesley MJ 《Journal of comparative psychology (Washington, D.C. : 1983)》2003,117(3):302-308
Hand preferences for a coordinated bimanual task were assessed in a sample of 31 captive gorillas (Gorilla gorilla) and 19 captive orangutans (Pongo pygmaeus) and were compared with chimpanzee (Pan troglodytes) hand preferences in subjects that were matched on the basis of age, sex, and rearing history. The task required that the apes remove food from the inside edges of a symmetrical polyvinyl chloride pipe presented to them in their home cages. The results indicate significant species differences with chimpanzees showing population-level right-handedness and orangutans showing population-level left-handedness. The gorillas showed a nonsignificant trend toward right-handedness. The results are discussed in terms of possible ecological or biomechanical factors that may influence hand preferences in different ape species. 相似文献
935.
In June 2002, the Advisory Committee on Immunization Practices (ACIP) approved draft recommendations concerning preparation for potential biological terror attacks that utilize the smallpox virus. ACIP recommends against both mandatory and voluntary vaccination of the general public. The present paper examines the moral and political considerations both for and against each of the general public vaccination options considered by the ACIP in the context of the state's authority over vaccination for the purposes of protecting public health. Although it is clear that compulsory mass vaccination is not justified at this time, the issues surrounding voluntary vaccination are more complex. Should smallpox vaccination prior to an outbreak be made available to the general public? The paper concludes that the vaccine should not be made available at this time. This conclusion, however, is based upon contingent features of current circumstances, which would change once an outbreak occurred. In the even of a terror-related outbreak of smallpox, the general public's access to voluntary vaccination would become justified, even in areas beyond where the outbreak has occurred. 相似文献
936.
Cooling blocks ITM and LTM formation and preserves memory 总被引:2,自引:0,他引:2
Sangha S Morrow R Smyth K Cooke R Lukowiak K 《Neurobiology of learning and memory》2003,80(2):130-139
In Lymnaea aerial respiratory behaviour can be operantly conditioned; snails learn not to perform this behaviour. Depending on the training procedure used, snails are competent to form either intermediate-term (ITM; lasting 1-3 h) or long-term (LTM; >4 h) memory. We found that cooling the snails for 1 h immediately after training was sufficient to block either ITM or LTM. Cooling snails for a similar period 10 or 15 min after cessation of training, failed to block ITM and LTM formation, respectively. Finally, we employed the cooling technique to extend both ITM and LTM. That is, cooling could prevent forgetting. Cooling extended LTM that normally persisted for 2 days to at least 8 days. These data are consistent with the hypothesis that forgetting is due to the learning and remembering of interfering events, and thus is an active process. 相似文献
937.
Ross LF 《Kennedy Institute of Ethics journal》2006,16(2):151-172
The past decade has witnessed the emergence of novel methods to increase the number of living donors. Although such programs are not likely to yield high volumes of organs, some transplant centers have gone to great lengths to establish one or more of them. I discuss some of the ethical and policy issues raised by five such programs: (1) living-paired and cascade exchanges; (2) unbalanced living-paired exchanges; (3) list-paired exchanges; (4) nondirected donors; and (5) nondirected donors catalyzing cascade exchanges. I argue that living-paired and cascade exchanges are ethically sound, but will lead to only a few additional transplants. Unbalanced exchanges and list-paired exchanges raise ethical issues that should limit their permissibility. Nondirected donations can be ethically sound with adherence to strict eligibility criteria and fair allocation procedures. Nondirected donors catalyzing cascade exchanges can be ethically sound provided that individuals with blood types O and B are not made worse off. 相似文献
938.
Farthing MJ 《Science and engineering ethics》2006,12(1):41-52
Although authors are usually considered to be the main perpetrators of research and publication misconduct, any person involved in the process has the potential to offend. Editors may breach ethical standards particularly with respect to conflicts of interest. In the same way that authors are now required to declare competing interests, notably commercial affiliations, financial interests and personal connections, so must editors. Editors can influence the chances of acceptance or rejection of a paper by reviewer selection. Reviewers should also be ready to disclose conflicts of interest. They must ensure that their reviews are evidence based and free from destructive criticism driven by self interest. It seems likely that ultimately we will progressively move towards 'open' peer review in which both the authors and the reviewers are known to each other. There is an urgent need for increased transparency of the relationship between editors and owners. The events of the last few years indicate that unless this interface is fully understood by all parties, conflicts may arise. There is also a need for a radical overhaul in the relationship between journals, journal editors and the biomedical industry. It is now increasingly accepted that all clinical trials should be registered in a centrally held database and that protocols should include the primary and secondary outcome measures and the intended approach to data analysis thereby avoiding opportunistic post hoc analyses. However, the even more radical proposal that journals should cease to publish clinical trials sponsored by industry deserves wider debate. 相似文献
939.
Milliken GW Ferra G Kraiter KS Ross CL 《Journal of comparative psychology (Washington, D.C. : 1983)》2005,119(4):430-439
Sixteen sifakas (11 Propithecus verreauxi coquereli, 2 Propithecus verreauxi verreauxi form majori, and 3 Propithecus tattersalli) were videotaped as they fed on leaves in an arboreal context. The hand used to feed and the hand used to maintain postural stability was coded. For each subject, the lateral bias of the hand used to feed was opposite the hand used in postural support. Seven sifakas displayed no bias for feeding or posture-related hand use, 7 sifakas displayed significant feeding-related reach preferences for pulling branches to the mouth (5 left- and 2 right-hand preferences), and 9 sifakas exhibited significant hand preferences for postural support (2 left-, 7 right-hand preferent). Although these data do not strongly support the postural origins theory of behavioral lateralization, the modal preference pattern for sifakas that displayed significant hand preferences for posture and feeding involve a left bias for feeding and a right bias for postural support. s reserved). 相似文献
940.
The two faces of typicality in category-based induction 总被引:6,自引:0,他引:6
Studies of category-based induction using different methods have found somewhat contradictory results for whether typical items are a stronger basis for induction. Typical category items are generally more similar to other category items than are atypical ones, and they are also more likely to be categorized into the category in question. We propose that the first aspect (representativeness) influences induction, but the second (uncertainty about the correct category) does not. Two experiments using artificial categories found support for this prediction. Two further experiments manipulated pictures of objects and also found that representativeness in the category influenced the strength of induction, but uncertainty of classification did not. Thus, the two aspects of typicality have different effects on category-based induction. 相似文献