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951.
The psychological stress reactions of 44 family medicine patients who were treated in the emergency room were examined approximately a year after the event. Patients were assessed on several psychological measures, including one for posttraumatic stress disorder (PTSD), and on their perception of how stressful the event was initially and now. Results show continuing stress reactions related to the emergency room event. Three patients endorsed symptoms indicating full PTSD and 13 appeared to have at least partial PTSD. Age appeared to be a factor in the presence of stress symptoms and in degree of perceived communication with the physician.  相似文献   
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In this paper the author challenges the prevailing view that contemporary writing in the medical humanities is serving the needs of the various health care disciplines. The current medical humanities literature assumes that physicians are the appropriate target group. This is most notably the case within health care ethics literature. There appears to be an unexamined assumption that physician-centric approaches to clinical ethical decision-making are the standard by which appropriate ethical practice is judged. The author challenges this assumption and addresses the problems that this approach engenders. The medical humanities literature appears to reinforce hierarchical, patriarchal arrangements which are themselves not morally neutral.  相似文献   
955.
Conclusion The past one hundred fifty years of debate over the use of animals in research and testing has been characterized mainly byad hominem attacks and on uncritical rejection of the other sides’ arguments. In the classroom, it is important to avoid repeating exercises in public relations and to demand sound scholarship. This paper is a modification of material originally included in the handbook which accompanied the American Association for the Advancement of Science (AAAS) Seminar “Teaching Ethics in Science and Engineering”, 10–11 February 1993.  相似文献   
956.
Gibson (1966, 1979) suggested that an important property of perception is that the observer is active. Two experiments were conducted to examine the benefits of active observation in determining dynamic spatial orientation. Subjects were presented with displays simulating locomotion through a three-dimensional environment. Active observers continuously controlled locomotion, whereas passive observers viewed the display. During the trial, the display was blacked out for a brief period, followed by a static image that was at either the correct or the incorrect orientation following the blackout. Subjects were required to indicate whether they were positioned at the correct extrapolated orientation. The presence or absence of orientation change, the type of change (changes in rotation about the depth axis [roll], horizontal axis [pitch], or forward translation), the duration of the blackout, and the consistency of change were varied. In addition, the experiments used either a compensatory or a pursuit tracking task. Active observers had greater sensitivity than did passive observers in detecting a change for both tracking tasks. Subjects in both experiments exhibited greater sensitivity in detecting inconsistent changes (relative to consistent changes), suggesting that the dynamics specified by optical flow were incorporated in extrapolated orientation. In addition, sensitivity decreased with an increase in blackout duration. The results are discussed in terms of an extrapolation model of perception that incorporates the responses executed by active observers.  相似文献   
957.
Manipulating stimulus spacing, stimulus frequency, or stimulus range usually affects intensity judgments. In six experiments, I investigated the locus of analogues of these contextual effects in a “difference” estimation task. When all stimuli elicited the same taste quality, stimulus distribution affected the scale values only when water was included in the stimulus set (Experiments 1–3). When the subjective ranges of two taste qualities were manipulated, different scale values were obtained for the separate qualities in the two conditions (Experiment 4). Manipulation of the expected response distribution did not affect the scale values or the responses (Experiments 5–6). It is concluded that shifts in stimulus distributions or stimulus ranges result in shifts in subjective scale values. The contextual effects can be interpreted as relative shifts of a number of gustatory continua, with water lying on a separate continuum. Proposed is a model for context-dependent judgments, consisting of four stages: stimulus classification, stimulus placement, continuum placement, and continuum projection.  相似文献   
958.
Although the eyes and the heart serve very different purposes, each receives autonomic innervation. Capitalizing on recent theoretical and technological innovations in the understanding and assessment of oculomotor and cardiovascular behavior, three experiments measured behavioral covariation between the oculomotor and cardiovascular systems. Measures of dark focus and dark vergence indexed oculomotor tone, and the spectral decomposition of variations in heart rate indexed cardiovascular control mechanisms. In Experiment 1, individual differences in cardiovascular parameters could predict individuals’ dark vergence (R2=.806) but not their dark focus (R2=.404). In Experiment 2, the same parameters were measured from subjects who experience either panic attacks (n=11) or blood phobia (n=9). Heart rate was positively correlated with dark vergence and the two subject groups were separable based on both oculomotor and cardiovascular variables. Using a within-subjects approach, Experiment 3 found that both dark vergence and dark focus tended to be nearer during sympathetic dominance of the heart than during parasympathetic dominance, within-subjects variations in cardiovascular parameters could predict dark focus, and between-subjects variations in interbeat intervals could predict dark vergence. Shared patterns of autonomic activation may be responsible for this eye-heart link.  相似文献   
959.
Cortisol can be used to indicate stress level as well as to monitor certain disease states. Although cortisol can be sampled from blood and urine, saliva sampling has decided advantages. Unfortunately, whole saliva contains a number of substances that can metabolize or bind with cortisol, potentially confounding analysis and quantitation. We introduce a semipermeable pouch that accumulates a contaminant-free salivary ultrafiltrate, thereby overcoming a number of the problems encountered with whole saliva. In three studies, we demonstrate accuracy and utility of the device for cortisol determination: (1) in an artificial medium, 60%–77% of the cortisol was recovered in the ultrafiltrate; (2) in vivo, ultrafiltrate cortisol correlated highly with whole-saliva cortisol collected under ideal conditions; and (3) ultrafiltrate cortisol evinced positive relationships with depression and cigarette use, consistent with studies in the literature. We conclude that this device and saliva-filtering technologies in general are useful in applications requiring quantitation of cortisol.  相似文献   
960.
Although infants have the ability to discriminate a variety of speech contrasts, young children cannot always use this ability in the service of spoken-word recognition. The research reported here asked whether the reason young children sometimes fail to discriminate minimal word pairs is that they are less efficient at word recognition than adults, or whether it is that they employ different lexical representations. In particular, the research evaluated the proposal that young children’s lexical representations are more “holistic” than those of adults, and are based on overall acoustic-phonetic properties, as opposed to phonetic segments. Three- and four-year-olds were exposed initially to an invariant target word and were subsequently asked to determine whether a series of auditory stimuli matched or did not match the target. The critical test stimuli were nonwords that varied in their degree of phonetic featural overlap with the target, as well as in terms of the position(s) within the stimuli at which they differed from the target, and whether they differed from the target on one or two segments. Data from four experiments demonstrated that the frequency with which children mistook a nonword stimulus for the target was influenced by extent of featural overlap, but not by word position. The data also showed that, contrary to the predictions of the holistic hypothesis, stimuli differing from the target by two features on a single segment were confused with the target more often than were stimuli differing by a single feature on each of two segments. This finding suggests that children use both phonetic features and segments in accessing their mental lexicons, and that they are therefore much more similar to adults than is suggested by the holistic hypothesis.  相似文献   
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