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881.
A computer program records, within the framework of the SKED minicomputer operating system, blood pressure and heart rate data in behavioral experiments. By repetitive (500-Hz) analog-to-digital conversions of a blood pressure waveform, the program finds and stores successive-beat systolic and diastolic pressures, and intersystolic intervals. SKED initiates and terminates blood pressure recording periods, and controls all experimental procedures. The program is currently operational, servicing four independent stations simultaneously, with sufficient computer operating time remaining to service low-priority background programs.  相似文献   
882.
High school students participated in a field experiment that tested the effects of exposure to early election returns in a nonpartisan referendum. On a pretest of attitudes, students stated their preferences on the issue of the school's grading policy. One week later, just before voting, subjects in the experimental condition received information announcing the probable outcome of the election. There was a significant relationship between class achievement level and (a) likelihood of changing vote, and (b) the direction of change. Students in the brighter classes changed their votes less frequently, but when they changed their preferences they showed a greater bandwagon effect. Students in the classes of lower academic achievement changed their votes more frequently, but when they changed their preferences they showed a greater underdog effect. Differences between the more typical political election in which bandwagon and underdog effects are seldom reported and the experimental election were discussed.  相似文献   
883.
884.
Recent studies of sequential decision making performance have utilized optimal dynamic programming solutions as the criteria for evaluating the quality of human decisions. The difficulties incumbent in increasing the dimensionality of dynamic programming formulations effectively prohibit their extension beyond the case of a single decision variable. In the following article an alternative optimization formulation for a two-decision-variable case is presented, followed by the development of a corresponding one-decision-variable problem. In addition, related methodological problems limiting the comparability of results among previous studies are presented. It is suggested that the proposed problem formulation and its accompanying interpretation for the decision maker largely eliminate these previous methodological problems. Furthermore, the problem formulation permits quantification of the relative weights that should optimally be placed on future decision periods in the multiple-stage decision problem.  相似文献   
885.
886.
Absolute vibrotactile thresholds were determined over the distal pad of the middle finger and thenar eminence of the right hands of five Ss. Measurements were made using eight frequencies between 25 and 700 Hz and seven contactor sizes between .0008 and 1.3 cm2. When plotted as a function of frequency, the threshold curve measured at the fingerpad with a .005-cm2 contactor is U shaped, with a maximum sensitivity in the region of 250 Hz. When plotted as a function of contactor size, the threshold decreases at a rate of 3 dB per doubling of the area.  相似文献   
887.
Pigeons responded on multiple variable-interval variable-interval schedules of reinforcement in an open and a closed economy. Equal duration components were increased in duration while the component rates of reinforcement were held constant, the component schedules were reversed, and component duration was decreased. In the open economy, daily sessions were limited to 1 hr, and subjects were maintained at 80% of their free-feeding weights through supplemental feeding when necessary in their home cages. In the closed economy, subjects were housed in their experimental chambers and no deprivation regimen was enforced. Relative response rate decreased as components were lengthened in the open economy, whereas in the closed economy relative rate increased as components were lengthened. Response proportions overmatched reinforcer proportions to a greater extent at long component durations in the closed economy, but there was no systematic effect of component duration on responding in the open economy.  相似文献   
888.
The purpose of this study was to determine whether different extents of mouth opening affect normal subjects' (N = 24; 12 women, 12 men) ability to discriminate differences in their interincisor bite force. Three mouth openings were selected including 50, 70, and 90 percent of maximum opening for each subject. Bite force was measured using a specially designed strain gauge scale which permitted subjects to monitor visually when their biting force equalled a preset resistance. Resistance forces of 500 and 1000 gm. were selected as standards. The procedure involved the use of a modified method of constant stimuli in which each subject was presented with a series of paired resistance settings, one at a time--the first resistance setting being the standard and the second resistance was the comparator. This paired-comparisons procedure was continued until the subjects' difference limen (DL) value (the threshold of discrimination between two forces) could be established. An analysis of variance yielded no significant differences in subjects' ability to discriminate bite force as a function of mouth opening.  相似文献   
889.
Discussions about the effects of television violence often fail to clearly define the nature of the effect and of the televised material. This article reviews the various facets of the issue and of the research that deals with them, focusing on one specific aspect that is often regarded as most crucial in public discussions and among researchers: the effect of actually televised entertainment programs on the aggressive behavior of children and adolescents. There is little research on that aspect of the issue and, in contrast to laboratory experiments on media violence, it does not show significant television effects. However, none of the existing studies reflect the changes in home entertainment available now as a result of cable television and VCRs and their possible effects on viewers.  相似文献   
890.
The cross-cultural validity of a North American personality inventory, namely, the Personality Research Form (Jackson 1984) was examined using 394 university students in the Philippines who were able to speak and read English. Scale validities, with self and peer ratings as criteria, were generally significant but modest. Moderate scale and peer rating reliabilities probably contributed to these results. Elevated scores on a PRF scale designed to detect careless responding suggested failure to understand instructions or insufficient motivation may also account for the findings. Interestingly, recalculating validities for subsamples comprising ‘dependable’ and ‘undependable’ subjects yielded no substantial differences in overall validity. Implications for cross-cultural personality assessment are discussed.  相似文献   
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