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781.
Ian G. Barbour 《Zygon》1996,31(1):101-110
Abstract. Both Roger Shinn and Robert Stivers ask whether technology has a momentum of its own that is difficult if not impossible to control (“autonomous technology” or “technological inevitability”). I reply that the difficulty in controlling technology is a product of economic and political institutions (such as corporate lobbying and campaign contributions) rather than of any inherent characteristics of technology. Against Stivers's assertion that the ecosystem should be the center of value in environmental ethics, I defend the process view that all beings are valuable, but they are not equally valuable in their richness of experience or their contribution to the experience of others. I also consider his caveats about ambiguities in the concept of sustainability. Two questions raised by Mary Gerhart are taken up: the difficulties of interdisciplinary writing and the role of theological ethics in discussions of public policy. In dialogue with Frederick Ferre I explore the role of alternative visions of the good life as a source of social change. In the face of diminished concern about social justice and environmental sustainability among citizens and in Congress since the book was written, I express long-range hope, but not optimism about the short-term prospects for change.  相似文献   
782.
In studies related to human movement, linked segment models (LSM's) are often used to quantify forces and torques, generated in body joints. Some LSM's represent only a few body segments. Others, for instance used in studies on the control of whole body movements, include all body segments. As a consequence of the complexity of 3-dimensional (3-D) analyses, most LSM's are restricted to one plane of motion. However, in asymmetric movements this may result in a loss of relevant information. The aim of the current study was to develop and validate a 3-D LSM including all body segments. Braces with markers, attached to all body segments, were used to record the body movements. The validation of the model was accomplished by comparing the measured with the estimated ground reaction force and by comparing the torques at the lumbo-sacral joint that resulted from a bottom-up and a top-down mechanical analysis. For both comparisons, reasonable to good agreement was found. Sources of error that could not be analysed this way, were subjected to an additional sensitivity analysis. It was concluded that the internal validity of the current model is quite satisfactory.  相似文献   
783.
Two experiments are reported in which, by means of a pointing task, we studied the stimulus-position effect, i.e. the inverted U-shape form of the reaction-time function in relation to stimulus position in tasks in which stimuli and/or responses are arranged in a horizontal array. The response consisted of aiming the index finger from a central starting point at a target area on a screen. Reaction time was the main dependent variable. The spatial relation between the position of the imperative signal and the position of the response was manipulated by varying the spatial S-R compatibility and physical distance that separated the positions of stimulus and response. The stimulus-position effect was shown to depend on the compatibility of the S-R relation (Exp. 1). In Exp. 2 it was found that the modulation of the stimulus-position effect by spatial compatibility disappeared completely when the distance between the positions of stimulus and response was reduced. None of the experiments revealed that the stimulus position effect depended on signal discriminability, which renders an interpretation of this effect in terms of perceptual processes unlikely. We argue that the attentional model of spatial coding provides the most reasonable explanation of the obtained reaction-time patterns.  相似文献   
784.
The purpose of this study was to determine the extent of agreement among a panel of rational-emotive therapy (RET) experts about the essence of RET. The panel of experts consisted of the 9 members of The International Training Standards and Review Committee of the Institute for Rational-Emotive Therapy in New York. The question that the experts were asked was an adaptation of a Talmudic story known in Jewish lore as “While Standing on One Foot.” Responses were assigned to either of 2 categories: general cognitive behavior therapy (CBT) or RET-specific. There seems to be a range of responses that capture the essence of RET. A strong case can be made for subsuming many aspects of CBT under RET because much of what is associated with CBT has its origins in RET. The confusion about where RET ends and general CBT begins goes to the very heart of RET's status today.  相似文献   
785.
786.
Dr. Neuro Transmitter, a psychotherapist in Paramus, New Jersey, provides services through an online, real-time consultation service known as CyberShrink, Inc., of Dallas, Texas. He is paid by the hour for his consultation services to subscribers who are billed by credit card through CyberShrink. One afternoon he logs on and is connected via private "chat channel" to a new subscriber to the service. She is Ann Hedonia of Simi Valley, California. Ten minutes into the session, Dr Transmitter recognizes that Ms. Hedonia is seriously depressed with suicidal ideation and is feeling on the edge of her ability to cope. He gently suggests that perhaps she ought to think about hospitalization near her home. Ms. Hedonia replies, "Even you don't care about me! That's it. I'm going to do it!" and disconnects. Discussion questions: Is offering psychotherapy services online ethical? What are Dr. Transmitter's obligations in general and at this particular moment to Ms. Hedonia? Suppose Ms. Hedonia has a complaint about Dr. Transmitter. From whom can she seek a remedy? Which state's laws apply regarding professional practice, confidentiality, or licensing qualifications? Must Dr. Transmitter be licensed in any state to offer this service?  相似文献   
787.
The present studies investigated the relationship between prepulse effects on the modification of the brainstem startle reflex and magnitude estimates of startle-eliciting stimuli. In Experiment 1, startle eyeblink responses were elicited in 24 students, half of whom were instructed to estimate the loudness of the startle stimulus (actual intensities of 80, 90, and 100 dB) and half of whom were instructed to estimate the magnitude of their eyeblink. When weak acoustic prepulses preceded the startle-eliciting stimulus, eyeblink amplitude was inhibited, and estimates of response magnitude decreased, but estimates of startle stimulus magnitude decreased only when 100-dB startle stimuli were presented. In Experiment 2, the same startle stimuli were preceded on some trials by a vibrotactile prepulse to the hand. In conditions in which startle amplitude was inhibited, startle stimulus magnitude estimates were not affected. This suggests that the effect of acoustic prepulses on 100-dB startle stimuli in Experiment 1 may have been due to loudness assimilation, an effect independent of the prepulse inhibition of startle responding.  相似文献   
788.
We tested the notion that better foster care adjustment would be observed when the temperaments of mothers and fathers were matched with those of adolescent foster children. We hypothesized that families in which foster parents and foster children had high (easy) scores on subscales of the Revised Dimensions of Temperament Scale (DOTS-R) would also report higher family functioning and higher foster care adjustment than parents and children from families in which one or both family members had low (difficult) scores on these scales. The hypotheses were supported when the mothers and fathers family assessments were used but rejected when the observations of the case managers and adolescents were tested. Methodological and substantive explanations for the findings are discussed and recommendation for foster care practice and continuing research are provided.  相似文献   
789.
This study investigated the prevalence of traumatic brain injury (TBI) in an inpatient psychiatric population. We hypothesized increased prevalence of TBI relative to the general population due to a variety of risk factors observed in psychiatric patients. One hundred (mean age = 34) psychiatric inpatients completed the revised Head Injury Questionnaire. Chart review of 17 subjects reporting injuries established whether injuries were documented in medical records. Sixty-eight percent of this psychiatric population reported one or more injuries in which they were unconscious or dazed. This number is higher than the prevalence in the general population. Injuries were generally of mild to moderate severity; multiple injuries were common. Chart review of 17 subjects reporting TBI indicated that histories of TBI had not been noted in the medical record. Finally, 63% of TBI subjects reported that their injury predated the onset of their psychiatric symptoms. These results suggest a possible role of TBI in psychiatric symptomatology and have implications for psychiatric treatment in this population.  相似文献   
790.
We investigated the ability of subjects to discriminate sugars with a whole-mouth forced-choice paradigm, in which a standard solution was compared with a test solution of varied concentration. Discrimination probabilities were U-shaped functions of test concentration: for 6 subjects and pairwise combinations of fructose, glucose, and sucrose, discriminability always declined to chance over a narrow range of test concentrations. At concentrations ≦ 100 mM, maltose was indiscriminable from fructose but discriminable at higher concentrations for 4 subjects. By analogy with themonochromacy of night vision, whereby any two lights are indiscriminable when their relative intensities are suitably adjusted, we call the gustatory indiscriminability of these sugarsmonogeusia. The simplest account of monogeusia is that all information about the indiscriminable sugars is represented by a single neural signal that varies only in magnitude. The discriminability of maltose from the other sugars at higher concentrations is consistent with the hypothesis that maltose also activates a second gustatory code.  相似文献   
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