全文获取类型
收费全文 | 1637篇 |
免费 | 146篇 |
出版年
2024年 | 3篇 |
2023年 | 16篇 |
2022年 | 21篇 |
2021年 | 32篇 |
2020年 | 59篇 |
2019年 | 61篇 |
2018年 | 87篇 |
2017年 | 72篇 |
2016年 | 90篇 |
2015年 | 83篇 |
2014年 | 86篇 |
2013年 | 223篇 |
2012年 | 140篇 |
2011年 | 113篇 |
2010年 | 83篇 |
2009年 | 85篇 |
2008年 | 93篇 |
2007年 | 67篇 |
2006年 | 42篇 |
2005年 | 38篇 |
2004年 | 69篇 |
2003年 | 37篇 |
2002年 | 31篇 |
2001年 | 15篇 |
2000年 | 14篇 |
1999年 | 8篇 |
1998年 | 9篇 |
1997年 | 6篇 |
1996年 | 4篇 |
1995年 | 3篇 |
1994年 | 4篇 |
1993年 | 7篇 |
1992年 | 4篇 |
1991年 | 4篇 |
1990年 | 6篇 |
1988年 | 4篇 |
1987年 | 3篇 |
1986年 | 3篇 |
1984年 | 2篇 |
1983年 | 3篇 |
1982年 | 4篇 |
1981年 | 3篇 |
1980年 | 6篇 |
1979年 | 4篇 |
1978年 | 3篇 |
1976年 | 9篇 |
1975年 | 2篇 |
1974年 | 5篇 |
1973年 | 3篇 |
1966年 | 2篇 |
排序方式: 共有1783条查询结果,搜索用时 15 毫秒
51.
The concept of informed consent was one of the most fruitful ideas that deeply changed the relationships between physicians
and their patients from paternalism to respect for the personal autonomy of subjects needing professional medical care. The
great progress in medicine, also involving the pharmaceutical industry, has created an increasing need to perform different
clinical and experimental trials. The evolution of clinical research in the last decades has influenced strongly the design
of these studies. One of the most important changes in this field has been the use of placebo groups in double-blind controlled
studies. The controversies have involved not only the use of placebo when standard or proven treatment was available, but
also some specific problems concerning the procedure of obtaining informed consent in such trials. This paper briefly presents
the evolution of informed consent in Poland as well as different ethical and legal problems concerning informed consent and
the use of placebo controls in clinical trials.
An earlier version of this paper was presented at an international conference, “Placebo: Its Action and Place in Health Research
Today,” held in Warsaw, Poland on 12–13 April, 2003. 相似文献
52.
Neurophysiological experiments with monkeys have demonstrated that working memory (WM) is associated with persistent neural
activity in multiple brain regions, such as the prefrontal cortex (PFC), the parietal cortex, and posterior unimodal association
areas. WM maintenance is believed to require the coordination of these brain regions, which do not function in isolation but,
rather, interact to maintain visual percepts that are no longer present in the environment. However, single-unit physiology
studies and traditional univariate analyses of functional brain imaging data cannot evaluate interactions between distant
brain regions, and so evidence of regional integration during WM maintenance is largely indirect. In this study, we utilized
a recently developed multivariate analysis method that allows us to explore functional connectivity between brain regions
during the distinct stages of a delayed face recognition task. To characterize the neural network mediating the on-line maintenance
of faces, the fusiform face area (FFA) was defined as a seed and was then used to generate whole-brain correlation maps. A
random effects analysis of the correlation data revealed a network of brain regions exhibiting significant correlations with
the FFA seed during the WM delay period. This maintenance network included the dorsolateral and ventrolateral PFC, the premotor
cortex, the intraparietal sulcus, the caudate nucleus, the thalamus, the hippocampus, and occipitotemporal regions. These
findings support the notion that the coordinated functional interaction between nodes of a widely distributed network underlies
the active maintenance of a perceptual representation. 相似文献
53.
The use of a distractor-assigned response slows later responding in a location negative priming task
Responding to a target's location takes longer when that location has recently contained a distractor event (ignored-repetition [IR] trial) relative to when it has been unoccupied (control trial). This is known as the location negative priming (NP) effect. We aimed to determine whether the elevated reaction time observed for IR trials was due to the reuse of a distractor location (location locus) and/or to the need to execute a (just inhibited) distractor response (response locus). We isolated these loci latency effects by using many-to-one and one-to-many location-response assignments. Our results showed that reusing a distractor location hastened target processing at that position (facilitative location locus), whereas the production of a distractor response was associated with a time cost (interfering response locus). Accordingly, part of the latency elevation seen with IR trials results from the need on these occasions to execute ajust inhibited (distractor) response, and, hence, the location NP effect has a response locus. 相似文献
54.
The present experiment examined the one-target advantage (OTA) with regard to saccadic eye movements. The OTA, previously found with manual pointing responses, refers to the finding that movements are executed faster when the limb is allowed to stop on the target compared to the situation where it has to proceed and hit a second target. Using an adapted limb movement OTA task, saccades of 5 degrees and 15 degrees were made to (a) a single target (one-target), (b) one target and immediately to another target without a change in direction (two-target-extension), and (c) one target and immediately back to the start location (two-target-reversal). Unlike manual movements, the movement times for the initial saccade in the two-target-extension condition were not prolonged compared to either of the other two conditions. Moreover, this pattern of results was found for both the shorter and longer amplitude saccades. The results indicate that the OTA does not occur in the oculomotor system and therefore is not a general motor control phenomenon. 相似文献
55.
Pierce JD Cohen AB Ulrich PM 《Journal of comparative psychology (Washington, D.C. : 1983)》2004,118(1):14-19
Substantial variation exists in the importance of olfaction in influencing individuals' preferences, yet the sources of this variation remain elusive. The authors explored responsivity to 2 odorants as 1 potential source. Participants (N = 258) completed the Affective Impact of Odor Scale and were assessed for responsivity to the putative human pheromone androstenone and amyl acetate. Results showed a significant relationship between odorant responsivity and self-reports of the influence of odors. People able to smell androstenone more commonly reported odors as having a negative effect on interpersonal relationships than did people anosmic to androstenone, whereas responsivity to amyl acetate was associated with positive effects of odors on relationships. Responsivity to certain odorants may be an important factor affecting human social interactions. 相似文献
56.
Orientational manoeuvres in the dark: dissociating allocentric and egocentric influences on spatial memory 总被引:2,自引:0,他引:2
Subjects in a darkroom saw an array of five phosphorescent objects on a circular table and, after a short delay, indicated which object had been moved. During the delay the subject, the table or a phosphorescent landmark external to the array was moved (a rotation about the centre of the table) either alone or together. The subject then had to indicate which one of the five objects had been moved. A fully factorial design was used to detect the use of three types of representations of object location: (i) visual snapshots; (ii) egocentric representations updated by self-motion; and (iii) representations relative to the external cue. Improved performance was seen whenever the test array was oriented consistently with any of these stored representations. The influence of representations (i) and (ii) replicates previous work. The influence of representation (iii) is a novel finding which implies that allocentric representations play a role in spatial memory, even over short distances and times. The effect of the external cue was greater when initially experienced as stable. Females out-performed males except when the array was consistent with self-motion but not visual snapshots. These results enable a simple egocentric model of spatial memory to be extended to address large-scale navigation, including the effects of allocentric knowledge, landmark stability and gender. 相似文献
57.
Hugo?WesterlundEmail author Anna?Bergstr?m T?res?Theorell 《Integrative psychological & behavioral science》2004,39(1):3-15
Thirty-two female participants in a mobilising labour market programme offering temporary, alternative employment in Sweden
were followed longitudinally for one year, including a six month post participation follow-up period. It can be hypothesised
that an important aspect of the physiological effects of unemployment is a change in the balance between anabolic and catabolic
activities in the body and that re-employment should lead to a shift towards anabolism. An earlier study of a smaller subset
of the data, however, including both men and women, showed increased prolactin and decreased dehydroepiadrosterone sulphate
(DHEA-s) levels, contrary to the initial hypothesis. In the present analysis, intended to elucidate these results, psychophysiological
data were summarised in two indices, one connected with anabolism (made up of testosterone and DHEA-s) and one with catabolism
(prolactin, γ-glutamyl transferase, aspartate amino transferase, α levuline amino transferase, and body mass index). In addition,
self-rated anxiety, depression, hopelessness and personal control were analysed. The results indicate that the effect of ‘better’
activities within the programme was a temporary increase in anabolism, possibly indicating lower stress levels, and the effect
of ‘worse’ activities, on the one hand, a temporary decrease in the catabolic index, probably reflecting repressed alcohol
consumption, and, on the other hand, impaired anabolism. There was also a general but transient decrease in depressiveness
measured by the Hospital Anxiety and Depression Scale. The results seem to imply that it is difficult to achieve lasting effects
through a relatively short participation in a mobilising programme. 相似文献
58.
Environmental support promotes expertise-based mitigation of age differences on pilot communication tasks 总被引:3,自引:0,他引:3
Morrow DG Ridolfo HE Menard WE Sanborn A Stine-Morrow EA Magnor C Herman L Teller T Bryant D 《Psychology and aging》2003,18(2):268-284
The authors investigated whether expertise is more likely to mitigate age declines when experts rely on environmental support in a pilot/Air Traffic Control (ATC) communication task. Pilots and nonpilots listened to ATC messages that described a route through an airspace, while they referred to a chart of the airspace. They read back (repeated) each message and then answered a probe question about the route. In a preliminary study, participants could take notes while listening to the messages and performing the read-back and probe tasks. In Experiment 1, opportunity to take notes was manipulated. Note taking determined when expertise mitigated age differences on the read-back task. With note taking, read-back accuracy declined with age for nonpilots but not for pilots. Without note taking, similar age-related declines occurred for pilots and nonpilots. Benefits of expertise, younger age, and note taking occurred for probe accuracy, but mitigation did not occur. The findings suggest that older adults take advantage of a domain-relevant form of environmental support (note taking) to maintain performance on some complex tasks despite typical age-related declines in cognitive ability. 相似文献
59.
The usage, derivation, and psychological, ethical, and legal aspects of slang terminology in medicine are discussed. The colloquial vocabulary is further described and a comprehensive glossary of common UK terms provided in appendix. This forms the first list of slang terms currently in use throughout the British medical establishment. 相似文献
60.
The psychological time perceptions and theperspectives defined for an organization's strategicplanning processes and plans by males and females ofdifferent hierarchical positions are studied. Thefindings obtained reinforce the socialization-centeredperspective: middle class males and females direct theorganization's strategic planning processes and planstoward similar time perspectives when positioned at the same hierarchical level. The findingsenable us to conclude that hierarchical position has astronger influence on strategic managerial behaviorsthan gender. 相似文献