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921.
Studies of crowding in various settings have shown that individuals are aroused and frequently suffer from ill health. Several studies have shown that it is possible to successfully intervene in residential, shopping, and classroom settings to reduce the negative effects of crowding. The present laboratory experiment assessed the effectiveness of two tactics commonly used by passengers in crowded mass transit settings. Results indicated that the two tactics, reading a newspaper or talking to others, failed to reduce arousal. An explanation for the failure of these tactics is offered.  相似文献   
922.
This study examined classroom-based instruction in restauranting skills for handicapped persons. Three male students were taught each of four skill components in sequential order: locating, ordering, paying, and eating and exiting. Training was implemented in a multiple baseline design across subjects and consisted of modeling and role playing in conjunction with photo slide sequences and a simulated ordering counter. The use of a menu containing general item classes and a finger matching procedure for identifying errors in the delivery of change greatly reduced the reading and math skills necessary to enter and complete the program. Periodic probes were conducted in a McDonald's restaurant prior to, during, and up to one-year following the termination of training. In addition, two probes (overt and covert observation) were conducted in a Burger King restaurant to assess further generalization to a location different from the one depicted throughout training. Results showed that students' performance on restaurant probes improved as a result of training, generalized to novel settings, maintained over an extended period of time, and was comparable to that of a normative sample of nonretarded persons.  相似文献   
923.
Several researchers who have compared the performance of dyslexic and normal-reading children on a variety of different tasks have suggested that dyslexic children may have subtle deficits in the phonemic analysis of spoken as well as written language. Thus it is of interest to know how children who have extraordinary difficulty learning to read can perform explicity auditory-phonetic tasks. Seventeen dyslexic children (10 years of age) and a group of 17 controls were administered tests of identification and discrimination of synthesized voiced stop consonants differing in place of articulation. These were tests of the type used to study categorical perception in adults, adapted for use with young children. Significant differences between dyslexics and controls were found in both kinds of tasks; the pattern of identification and discrimination differences suggests an inconsistency in the dyslexics' phonetic classification of auditory cues. A significant relationship was found between reading level and speech discrimination.  相似文献   
924.
925.
A system for monitoring blood pressure or other physiological variables in the unanesthetized and chronically instrumented dog is described. An indwelling catheter attaches to a pressure transducer affixed to the underside of a leather shield, which snaps onto a custom-fitted leather vest worn by the dog. The transducer cable ascends vertically through a hollow, flexible, stainless steel tether, which is attached at the lower end to the leather shield and at the upper end to a fluid and electrical swivel. The swivel is attached to an overhead counterbalanced boom assembly, which moves in concert with the dog, maintaining a constant minimal tension on the tether. The boom assembly is attached to a wall plate via a universal joint approximately 7 ft above floor level. Dogs can be maintained comfortably in this system 24 h/day over periods of months, with freedom of posture and movement, including rotational behavior. The system is economical to construct and provides versatile stimulation and record-ing capability and reliable long-term performance.  相似文献   
926.
In this paper are explored the ethical implications of the answers to three questions: Whether or not a diseased state is discrete; the criteria by which that question is answered; and how the diseased state is to be identified. Examples are given showing that some states appear to be clearly discrete, and others equally clearly not discrete. The nature of the pertinent evidence will be affected accordingly. It is shown that a slavish and inappropriate concern with categories leads to anomalous ethics. Finally, it is suggested that many of these problems may be avoided by centering the ethics of medicine on optimizing the welfare of the patient rather than by thinking in terms of categorical disease.  相似文献   
927.
A procedure is described for simple conversion of a printing calculator to an inexpensive printing counter. The unit is particularly useful for unattended data collection. A timing circuit controls printout of accumulated data at specified time intervals.  相似文献   
928.
Several resources are available to the person seeking to develop a laboratory course that utilizes microprocessors. Several roles for such equipment are envisioned, and some of the issues regarding types of equipment and programming languages are addressed.  相似文献   
929.
Recent research has demonstrated that focal regions of color space are cognitively more salient than nonfocal regions. Employing a linguistic hedge task, the experiment here sought mainly to verify the cognitive primacy of loci representing Berlin and Kay’s first four chromatic categories over foci representing the remainder. The experimental results failed to support the primacy hypothesis, an outcome that gives rise to a number of theoretical implications. Additional questions in the analysis concerned the relationship between the salience of a color and its lightness (Munsell value) and saturation (Munsell chroma). While the results permit no simple interpretation for lightness, a definite trend emerged in the case of saturation.  相似文献   
930.
The perception of distance and size in the presence of optical gradient information was investigated under four viewing conditions—binocular view with and without head motion, and monocular view with and without head motion. Subjects (60 adults) matched distance intervals (from 15 to 127 cm) and heights of a target triangle (from 5 to 15 cm) by adjusting the length of a metal tape. Both linear and power functions were fitted to each individual’s distance judgments, and the competing perceptual models were compared. For both models, it was found that binocular information was sufficient to specify relative, but not absolute, distance, that monocular information was sufficient to specify an orderly relation between target distance and judgment but not absolute distance, that average error was less in the binocular conditions, and that perceived distance was not affected in either condition by the addition of head motion. The analysis of size judgments revealed that monocular and binocular judgments did not differ, that matches made with and without head motion did not differ, and that, in all conditions, matches exceeded target heights by an average 30% to 40%. Judged size was also analyzed as a function of target distance. In all conditions but monocular view with head motion, the effect of distance was to increase size judgments. The distance judgments support the hypothesis (Purdy, 1958) that the binocular stimulus carries information that the monocular stimulus does not; they fail to support the hypothesis (Gibson, 1966) that observer motion adds information to the static stimulus. The size judgments support neither hypothesis but suggest an independence of perceived size from perceived distance.  相似文献   
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