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931.
932.
Hellgren C Akerud H Jonsson M Sundström Poromaa I 《Stress (Amsterdam, Netherlands)》2011,14(6):627-633
Stress regulation during pregnancy is considered to be connected to the timing of labour initiation. Although increasing knowledge is emerging on the regulation of parturition, there is currently no way to predict the start of spontaneous labour in women. The main aim of this study was to assess pain threshold and the sympathetic nervous system response to cold pain in relation to the onset of labour in healthy pregnant women. Ninety-three pregnant women were recruited and assessed for skin conductance (SC) activity during a cold pressor test in gestational week 38. Pain threshold and cold endurance were also measured and the results were compared with data obtained from hospital records. Seventy-four women had a spontaneous labour onset and a valid SC measurement. SC activity during the cold pressor test decreased significantly with the number of days left to spontaneous parturition. This may indicate a gradual decrease in sympathetic autonomic nervous system reactivity even during the last weeks of pregnancy. Measuring SC activity during mild stress provocation is a rapid and non-invasive means to study variation in sympathetic reactivity during pregnancy, and may be useful in research on stress regulation in pregnancy and its relation to labour initiation. 相似文献
933.
Räikkönen K Seckl JR Pesonen AK Simons A Van den Bergh BR 《Stress (Amsterdam, Netherlands)》2011,14(6):590-603
A suboptimal prenatal environment may induce permanent changes in cells, organs and physiology that alter social, emotional and cognitive functioning, and increase the risk of cardiometabolic and mental disorders in subsequent life ("developmental programming"). Although animal studies have provided a wealth of data on programming and its mechanisms, including on the role of stress and its glucocorticoid mediators, empirical evidence of these mechanisms in humans is still scanty. We review the existing human evidence on the effects of prenatal maternal stress, anxiety and depression, glucocorticoids and intake of liquorice (which inhibits the placental barrier to maternal glucocorticoids) on offspring developmental outcomes including, for instance, alterations in psychophysiological and neurocognitive functioning and mental health. This work lays the foundations for biomarker discovery and affords opportunities for prevention and interventions to ameliorate adverse outcomes in humans. 相似文献
934.
We review studies that investigate negative social cognitions of socially anxious youth in relation to two specific domains:
interpretation of ambiguous social situations and self-evaluation of social performance, including social skills and nervous
behaviors. In this review, we address the question whether socially anxious youth’s negative perceptions are distortions of
reality or reflect a kernel of truth as compared to other sources of information including independent adult observers and
age peers. Studies key to this question are those that investigate not only the social perceptions themselves but also the
social behavior of socially anxious youth. Hence the selection of studies for the review was based on this criterion. From
the relevant literature it is, as yet, unclear whether the negative interpretations of ambiguous social situations shown by
socially anxious youth are distorted or a reflection of reality. Socially anxious youth’s self-evaluations of social skills
appear partly distorted and partly true, depending on the person judging the social skills. In contrast, self-evaluations
of nervous behaviors appear distorted. The studies reviewed indicate that research would benefit from including a wider range
of perceptions from persons relevant to the socially anxious youth’s daily social environment, not only parents and teachers
but also their age peers. 相似文献
935.
Petersen HV Domanska K Bendahl PO Wong J Carlsson C Bernstein I Esplen MJ Nilbert M 《Journal of genetic counseling》2011,20(3):308-313
Learning about hereditary cancer may influence an individual’s self-concept, which otherwise represents a complex but stable
cognitive structure. Recently, a 20-statement self-concept scale, with subscales related to stigma-vulnerability and bowel
symptom-related anxiety, was developed for Lynch syndrome. We compared the performance of this scale in 591 mutation carriers
from Denmark, Sweden and Canada. Principal component analysis identified two sets of linked statements—the first related to
feeling different, isolated and labeled, and the second to concern and worry about bowel changes. The scale performed consistently
in the three countries. Minor differences were identified, with guilt about passing on a defective gene and feelings of losing
one’s privacy being more pronounced among Canadians, whereas Danes more often expressed worries about cancer. Validation of
the Lynch syndrome self-concept scale supports its basic structure, identifies dependence between the statements in the subscales
and demonstrates its applicability in different Western populations. 相似文献
936.
Long-term synaptic plasticity exhibits distinct phases. The synaptic tagging hypothesis suggests an early phase in which synapses are prepared, or "tagged," for protein capture, and a late phase in which those proteins are integrated into the synapses to achieve memory consolidation. The synapse specificity of the tags is consistent with conventional neural network models of associative memory. Memory consolidation through protein synthesis, however, is neuron specific, and its functional role in those models has not been assessed. Here, using a theoretical network model, we test the tagging hypothesis on its potential to prolong memory lifetimes in an online-learning paradigm. We find that protein synthesis, though not synapse specific, prolongs memory lifetimes if it is used to evaluate memory items on a cellular level. In our model we assume that only "important" memory items evoke protein synthesis such that these become more stable than "unimportant" items, which do not evoke protein synthesis. The network model comprises an equilibrium distribution of synaptic states that is very susceptible to the storage of new items: Most synapses are in a state in which they are plastic and can be changed easily, whereas only those synapses that are essential for the retrieval of the important memory items are in the stable late phase. The model can solve the distal reward problem, where the initial exposure of a memory item and its evaluation are temporally separated. Synaptic tagging hence provides a viable mechanism to consolidate and evaluate memories on a synaptic basis. 相似文献
937.
Marc-André Reinhard Oliver Dickhäuser Tamara Marksteiner Siegfried L. Sporer 《Social Psychology of Education》2011,14(3):299-318
In a study with 365 teacher students, 447 teacher trainees, and 123 teachers, the ability to detect students’ deception was
tested. Participants judged the credibility of videotaped students who were accused of academic dishonesty (having cheated
in a test). Half of these messages were actually true (students had not cheated on the test) and half of them were deceptive
(students had cheated on the test). As expected and in line with findings on the influence of expertise on the ability to
detect deception from other fields, we found that the overall accuracy rate of teachers was not higher than that of teacher
trainees and teacher students. Moreover, we found no effect of teaching experience (years working as a teacher) on overall
detection of deception accuracy. Interestingly, teachers were found to have a stronger truth bias and therefore had a lower
accuracy in detecting deceptive messages than teacher students and teacher trainees (veracity effect). While teacher characteristics
accounted for very little variance, senders’ opportunity to prepare and their gender had strong effects. Detection accuracy
was higher for messages where the student had no chance to prepare before being accused of cheating. Overall, independent,
or experience, participants hold inaccurate beliefs about deception. 相似文献
938.
The Mirror Neuron System hypothesis stating that observed actions are projected onto the observer’s own action system assigns an important role to development, because only actions mastered by the observer can be mirrored. The purpose of the present study was to investigate whether there is evidence of a functioning mirror neuron system (MNS) in 8-month-old infants. High-density EEG was used to assess the mu rhythm desynchronization in an action observation task where the infants observed a live model. To reduce noise, ICA decompositions were used. The results show a higher desynchronization of the mu rhythm when infants observed a goal-directed action than when they observed a spatially similar non-goal-directed movement. The localizations of the sources are in agreement with those proposed by the MNS hypothesis. This indicates that the MNS is functioning at this age. 相似文献
939.
Torbjörn Tännsjö 《Ethical Theory and Moral Practice》2011,14(4):397-406
Given a reasonable coherentist view of justification in ethics, applied ethics, as here conceived of, cannot only guide us,
in our practical decisions, but also provide moral understanding through explanation of our moral obligations. Furthermore,
applied ethics can contribute to the growth of knowledge in ethics as such. We put moral hypotheses to crucial test in individual
cases. This claim is defended against the challenges from moral intuitionism and particularism. 相似文献
940.
Die chronische bipolare Depression bei ?lteren Menschen ist eine klinische Herausforderung und erfordert unter Umst?nden,
wie der vorliegende Fallbericht zeigt, Behandlungswege, die von Leitlinien nicht unbedingt abgedeckt werden. 相似文献