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161.
162.
Wendy C. McKinnon Alan E. Guttmacher Marc S. Greenblatt Bruce E. Compas Sandy May Roy E. Cutler David W. Yandell 《Journal of genetic counseling》1997,6(2):131-145
In response to many scientific discoveries linking cancer in certain families to inherited factors, the Vermont Cancer Center established the Familial Cancer Program (FCP) in December 1993. This multifaceted program combines the expertise of clinicians and researchers in many disciplines, including genetics, oncology, psychology, and molecular biology. The program's goals are identification of families in its region with excess cancer, provision of clinical services to such families, and use of research protocols when available and appropriate. This article describes the experience of setting up a familial cancer program in a rural area and discusses both successes and challenges in such an endeavor. 相似文献
163.
Barbara J. Myers Ph.D. Gena C. Britt M.S. Diane E. Lodder M.S. Kathy A. Kendall B.S. Margaret G. Williams-Petersen Ph.D. 《Journal of child and family studies》1992,1(4):393-415
We review the effects of maternal cocaine use on the developing human fetus and infant in terms of methodological problems; the physiological action of cocaine on adults and on the developing fetus; the epidemiology of cocaine use; effects on fetal and infant mortality; growth of cocaine-exposed fetuses and infants; physical anomalies; evidence for and against infant withdrawal from cocaine; neurological effects; behavioral effects as shown by the NBAS; findings related to mother-infant interaction and emotional development; and parenting by cocaine-using mothers. Findings in most areas should be considered preliminary due to methodological problems. Published studies of long-term development are not yet available. In general, deleterious consequences of prenatal cocaine exposure are found for some portion of prenatally exposed infants. However, many findings of no difference are also available in methodologically well-controlled studies. 相似文献
164.
This article reviews theory and research regarding the physiology, situational and dispositional antecedents, behavioral concomitants, and interpersonal consequences of social blushing and offers a new theoretical account of blushing. This model posits that people blush when they experience undesired social attention. Puzzling questions involving blushing in solitude, the phenomenology of blushing, types of blushing, and blushing in dark-skinned people are discussed. 相似文献
165.
Five experiments measured reaction time (RT) to detect the presence or absence of a simple volumetric shape (target) dependent on the number of display items (distractors) and their depicted three-dimensional (3-D) orientation. Experiments 1-4 examined every pairwise combination of two different simple volumetric shapes in two 3-D orientations. Conditions exhibiting "pop-out" could be predicted by differences in their two-dimensional (2-D) features. Conditions in which search was slower support previously found search asymmetries for particular 2-D features. When the distractors were a mixture of the other shapes in the same 3-D orientation, search was serial, except when the target had a curved principal axis (Experiment 5). The results suggest that these simple volumetric shapes are not processed preattentively. 相似文献
166.
Larry May 《The Journal of value inquiry》1992,26(1):7-22
I am grateful to Marcia Baron, Dorothy Leland, Rod Bertolet, Laurence Thomas, Patricia Curd, Lilly Russow and Marilyn Friedman for their very helpful comments on earlier drafts of this paper. 相似文献
167.
168.
Age-related performance changes on a dichoptic viewing task were examined with twenty-five (25) individuals in a cross-sectional design. Using a double-report procedure, subjects were asked to identify two different consonant-vowel graphemes presented separately to the same foveal area of each eye (i.e., dichoptic stimulation). Stimuli were presented at stimulus-onset asynchronies (SOAs) ranging from 0 to 300 msec in 50-msec steps. Results indicated that the number of both-correct trials (i.e., correct reports of both stimuli in a dichoptic pair) significantly increased with age, while single-correct trials (a correct report of only one stimulus in the pair) significantly decreased with age. In addition, the shape of the masking functions indicated lagging stimuli were reported more accurately than leading stimuli at SOAs of 50–300 msec for all subjects. Younger subjects exhibited peak masking effects for synchronous presentations (0-msec SOA) while older individuals showed peak masking at SOAs of 50 msec. Results suggest developmental performance changes noted in processing visual information parallel, to a remarkable degree, those observed in processing auditory information. 相似文献
169.
The issue of whether McCollough effects transfer interocularly was examined in two experiments. In Experiment 1, as in previous experiments, no interocular transfer of McCollough effects was obtained when subjects adapted monocularly to externally present patterns with their unused eyes fully occluded. However, when subjects adapted monocularly (with the unused eye fully occluded) to visual images of those patterns superimposed on physically present chromatic backgrounds, McCollough effects transferred interocularly. In Experiment 2, subjects adapted to either physically present patterns or to images of those patterns (as in Experiment 1), but the unused eye was exposed to unpatterned diffuse white light. In contrast to Experiment 1, the externally adapted subjects showed interocular transfer of McCollough effects. In Experiment 2, the magnitude of the interocular transfer effects produced by imagery was significantly larger than the magnitude of the effects produced by external adaptation, but the magnitude of the imagery-induced aftereffects did not differ from Experiment 1 to Experiment 2. These results extend earlier findings by Kunen and May (1980) and show that McCollough effects can be produced through adaptation to imagery, even though the direction of the imagery-induced aftereffects indicates adaptation to higher spatial frequencies whereas externally derived aftereffects indicate adaptation to lower spatial frequencies. It is concluded that failure of previous studies to obtain interocular transfer of McCollough effects may have resulted from complete occlusion of the contralateral eye. These data point up some interesting similarities and some important differences between imagery and actual vision. The implications for analogical models of visual imagery are discussed. 相似文献
170.
Modifying drug-reinforced behavior by altering the economic conditions of the drug and a nondrug reinforcer. 总被引:2,自引:2,他引:0 下载免费PDF全文
M E Carroll G G Carmona S A May 《Journal of the experimental analysis of behavior》1991,56(2):361-376
Six rhesus monkeys were trained to self-administer orally delivered phencyclidine (0.25 mg/mL) and saccharin (0.03% wt/vol) under concurrent fixed-ratio 16 schedules. In Condition 1 the fixed-ratio requirement for phencyclidine was changed from 16 to 4, 8, 16, 32, 64, 128 and 16 while the fixed-ratio requirement for saccharin deliveries remained constant at 16. In Condition 2 the fixed-ratio value for saccharin was systematically altered while the fixed-ratio requirement for phencyclidine remained at 16, and in Condition 3 the fixed-ratio requirements for both phencyclidine and saccharin were altered simultaneously. Water was then substituted for saccharin, and the series of fixed-ratio manipulations was replicated. The phencyclidine concentration was reduced to 0.125 mg/mL and Conditions 1 and 3 were repeated. When the fixed-ratio requirement for phencyclidine was increased and the fixed-ratio requirement for saccharin or water remained fixed at 16, phencyclidine deliveries decreased when saccharin (vs. water) was concurrently available. The magnitude of the decrease ranged from 20% to 90% (of the concurrent water condition) as the fixed-ratio requirement for phencyclidine increased from 4 to 128. When the fixed-ratio requirement for phencyclidine remained at 16 and the fixed-ratio requirements for concurrent saccharin or water varied between 4 and 128, phencyclidine deliveries decreased by 30% to 40% due to the concurrent availability of saccharin (vs. water). This decrease occurred only at the three lowest fixed-ratio values when saccharin intake was relatively high. When the fixed-ratio requirements for both phencyclidine and concurrent saccharin or water were varied simultaneously, phencyclidine deliveries were reduced from 20% to 45% when saccharin (vs. water) was concurrently present. There was little effect of reducing the phencyclidine concentration when the data were analyzed in terms of unit price (responses per milligram). Thus, changes in the fixed-ratio requirement or drug concentration were functionally similar, and unit price of phencyclidine was the variable that was influenced by the presence of concurrent saccharin. These data indicate that drug-reinforced behavior is substantially reduced when the environment is enriched with an alternative nondrug reinforcer. The economic context in which these substances are presented is an important determinant of drug-reinforced behavior. 相似文献