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111.
Regional cerebral blood flow (rCBF) may be measured with inhalation techniques that use end-expired values of radioactivity to estimate the isotope concentration in arterial blood. These end-expired data are used as an input function in a mathematical equation to derive rCBF. End-expired air is assumed normally to be in equilibrium with the arterial blood at the alveolar surface of the lung during regular (passive) breathing; this assumption may not be valid during continuous phonation. We therefore have analyzed breathing (inhalation/exhalation) patterns and end-expired radioactivity (133Xe) during (1) speaking, (2) singing, and (3) humming of the national anthem, and also during (4) passive breathing. Statistically significant differences in breathing patterns were measured between a group of nonmusicians and two groups of musicians (singers) during the phonation tasks: The nonmusicians breathed more often (and more rapidly) and exhibited less variability in their breathing patterns than did the musicians. Notwithstanding these differences, the shapes of smoothed functions derived from the end-expired values were not influenced appreciably during phonation (except possibly during talking). The latter finding suggests that estimates of rCBF derived with these data should not be confounded seriously because of the continuous phonation. 相似文献
112.
Several theories have been presented that predict differences between women and men in attitudes toward the environment due to differences in sex roles. Research on which these theories can be tested has tended to examine general environmental concern, and the results have generally been weak and inconclusive. Using an approach suggested in the literature, this study examines sex differences in concern and knowledge, using multi-item scales for each, about one environmental issue — acid rain. The results contradict the theories being tested, however: if there is a sex difference, men are found to be more concerned and knowledgeable about the environmental problem. 相似文献
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The impact of pre-employment integrity testing on employee turnover and inventory shrinkage losses 总被引:1,自引:0,他引:1
Thomas S. Brown Dr. John W. Jones William Terris Brian D. Steffy 《Journal of business and psychology》1987,2(2):136-149
A major home improvement chain located primarily in the western United States initiated the use of thePersonnel Selection Inventory, a written integrity test, as part of its pre-employment hiring process. For two years only, those job applicants who passed this test and other pre-employment criteria were hired by the chain. Following the introduction of the inventory, there was: (1) a 50% reduction in the number of employee terminations for theft, illegal drug use, and violence over a five year period and (2) a savings in shrinkage losses that amounted to over two million dollars over a two year period. 相似文献
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118.
The influence of alcohol and loud music on analytic versus holistic processing was examined in classification, concept learning, and embedded figures tasks. In the classification task, loud music reduced analytic responding by individuals who had consumed alcohol and increased analytic responding by individuals who had received placebo drinks. Alcohol also decreased the speed with which individuals were able to generate analytic responses in the classification task and decreased analytic performance on the embedded figures test. Alcohol slowed the rate of learning in the concept-learning task but did not lead to less analytic responding in that task. The results are consistent with the idea that alcohol slows the rate of information processing, particularly in tasks requiring visual analysis of stimuli. 相似文献
119.
Thomas P. Pallmeyer Edward B. Blanchard Lawrence C. Kolb 《Behaviour research and therapy》1986,24(6):645-652
The psychophysiological responses of heart rate (HR), systolic and diastolic blood pressure, skin conductance level and forehead electromyogram were compared during: rest, mental arithmetic and combat sounds of gradually increasing intensity for five groups of Ss: Vietnam veterans with post-traumatic stress disorder (PTSD); Vietnam veterans without PTSD but with comparable levels of combat experience; Vietnam veterans with other psychiatric disorders; Vietnam-era veterans; and nonveteran phobics. HR response to low-intensity combat sounds provided good discrimination between veterans with PTSD and the other groups and seems to resemble a conditioned emotional response. 相似文献
120.
Adolescent alcoholism in Benin City, Nigeria 总被引:1,自引:0,他引:1
O A Pela 《Adolescence》1986,21(82):487-492
The consumption of alcohol by Nigerian adolescents is investigated. Adolescence and alcoholism as applied in this study are defined, and the financial costs and physical and mental effects of alcohol use are described. The author used unobtrusive methods to gather data, visiting three nightclubs and an amusement park where alcohol is served in order to observe and interview adolescents. The findings show that adolescents begin drinking at an early age and consume large quantities of beer. The findings are consistent with those of other epidemiological studies. Finally, recommendations for controlling adolescent alcohol use are made. 相似文献