全文获取类型
收费全文 | 223篇 |
免费 | 17篇 |
出版年
2018年 | 2篇 |
2017年 | 4篇 |
2016年 | 4篇 |
2015年 | 3篇 |
2014年 | 5篇 |
2013年 | 7篇 |
2012年 | 8篇 |
2011年 | 7篇 |
2010年 | 12篇 |
2009年 | 7篇 |
2008年 | 9篇 |
2007年 | 10篇 |
2006年 | 12篇 |
2005年 | 10篇 |
2004年 | 4篇 |
2003年 | 6篇 |
2002年 | 8篇 |
2001年 | 8篇 |
2000年 | 5篇 |
1999年 | 9篇 |
1998年 | 8篇 |
1997年 | 3篇 |
1995年 | 3篇 |
1994年 | 4篇 |
1993年 | 2篇 |
1992年 | 3篇 |
1991年 | 6篇 |
1990年 | 8篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1985年 | 6篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1977年 | 2篇 |
1975年 | 3篇 |
1970年 | 2篇 |
1969年 | 2篇 |
1966年 | 5篇 |
1965年 | 2篇 |
1964年 | 2篇 |
1961年 | 3篇 |
1960年 | 3篇 |
1957年 | 1篇 |
1953年 | 1篇 |
1952年 | 2篇 |
1945年 | 1篇 |
1912年 | 1篇 |
排序方式: 共有240条查询结果,搜索用时 15 毫秒
11.
Jamin Halberstadt Joshua Conrad Jackson David Bilkey Jonathan Jong Harvey Whitehouse Craig McNaughton Stefanie Zollmann 《PloS one》2016,11(3)
Social psychology is fundamentally the study of individuals in groups, yet there remain basic unanswered questions about group formation, structure, and change. We argue that the problem is methodological. Until recently, there was no way to track who was interacting with whom with anything approximating valid resolution and scale. In the current study we describe a new method that applies recent advances in image-based tracking to study incipient group formation and evolution with experimental precision and control. In this method, which we term “in vivo behavioral tracking,” we track individuals’ movements with a high definition video camera mounted atop a large field laboratory. We report results of an initial study that quantifies the composition, structure, and size of the incipient groups. We also apply in-vivo spatial tracking to study participants’ tendency to cooperate as a function of their embeddedness in those crowds. We find that participants form groups of seven on average, are more likely to approach others of similar attractiveness and (to a lesser extent) gender, and that participants’ gender and attractiveness are both associated with their proximity to the spatial center of groups (such that women and attractive individuals are more likely than men and unattractive individuals to end up in the center of their groups). Furthermore, participants’ proximity to others early in the study predicted the effort they exerted in a subsequent cooperative task, suggesting that submergence in a crowd may predict social loafing. We conclude that in vivo behavioral tracking is a uniquely powerful new tool for answering longstanding, fundamental questions about group dynamics. 相似文献
12.
McNaughton BL 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2003,358(1432):629-634
The early history of the experimental work leading to the discovery that long-term potentiation (LTP) embodies Hebb's principle of association is described. In addition, the fallacy underlying the sometimes presumed distinction between 'cooperativity' and 'associativity' in the induction of LTP is pointed out. 相似文献
13.
NMDA receptor antagonism blocks experience-dependent expansion of hippocampal "place fields". 总被引:4,自引:0,他引:4
In agreement with theories of sequence learning, hippocampal place representations expand asymmetrically during repeated route following. This behaviorally induced, experience-dependent expression of neuronal plasticity was blocked by the NMDA(R) antagonist CPP, suggesting that it may result from the temporal asymmetry and associative properties of LTP. NMDA(R) antagonism, however, had no effect on the range of the progressive shift of firing phase of hippocampal cells, relative to the theta rhythm, as the rat traverses the cell's "place field." Thus, when place fields normally expand with experience, the relationship between firing phase and position is altered, as predicted by models that account for "phase precession" on the basis of asymmetry of synaptic connection strengths. These effects of CPP mimic changes that occur during normal aging, suggesting mechanisms by which sequence learning deficits may arise in aged animals. 相似文献
14.
Jolanda?HM?van Bilsen Josée?PA?Wagenaar-Hilbers Maarten?JF?van der Cammen Mariska?EA?van Dijk Willem?van Eden Marca?HM?WaubenEmail author 《Arthritis research & therapy》2002,4(4):R2
We have recently found that matrix metalloproteinases (MMPs) are targets for T-cell and B-cell reactivity in experimental
arthritis. In the present article, we investigate whether modulation of MMP-specific T-cell responses could influence the
course of adjuvant arthritis (AA). Lewis rats were treated nasally with MMP peptides prior to or after AA induction. Administration
of the MMP-10 or the MMP-16 peptide prior to AA induction reduced the arthritic symptoms. In contrast, administration of the
MMP-10 peptide after AA induction aggravated the arthritic symptoms. The present study shows the possible usefulness of MMP
peptides for immunotherapy. However, a clear understanding of proper timing of peptide administration is crucial for the development
of such therapies. 相似文献
15.
Characterization of terminal NeuNAcalpha2-3Galbeta1-4GlcNAc sequence in lipooligosaccharides of Neisseria meningitidis 总被引:1,自引:0,他引:1
Group B and C Neisseria meningitidis are the major cause of meningococcal
disease in the United States and in Europe. N . meningitidis
lipooligosaccharide (LOS), a major surface antigen, can be divided into 12
immunotypes of which L1 through L8 were found among Group B and C
organisms. Groups B and C but not Group A may sialylate their LOSs with
N-acetylneuraminic acid (NeuNAc) at the nonreducing end because they
synthesize CMP-NeuNAc. Using sialic acid-galactose binding lectins as
probes in an ELISA format, six of the eight LOS immunotypes (L2, L3, L4,
L5, L7, and L8) in Groups B and C bound specifically to Maackia amurensis
leukoagglutinin (MAL), which recognizes NeuNAcalpha2- 3Galbeta1-4GlcNAc/Glc
sequence, but not to Sambucus nigra agglutinin, which binds
NeuNAcalpha2-6Gal sequence. The combination of SDS-PAGE and MAL-blot
analyses revealed that these six LOSs contained only the
NeuNAcalpha2-3Galbeta1-4GlcNAc trisaccharide sequence in their 4.1 kDa LOS
components, which have a common terminal lacto-N-neotetraose (LNnT,
Galbeta1-4GlcNAcbeta1-3Galbeta1-4Glc) structure when nonsialylated as shown
by previous studies. The LOS-lectin binding was abolished when the LOSs
were treated with Newcastle disease viral neuraminidase which cleaves
alpha2-->3 linked sialic acid. Methylation analysis of a representative
LOS (L2) confirmed that NeuNAc is 2-->3 linked to Gal. Thus, these LOSs
structurally mimic certain glycolipids, i.e., paragloboside (LNnT-ceramide)
and sialylparagloboside and some glycoproteins in having LNnT and
N-acetyllactosamine sequences, respectively, with or without alpha2-->3
linked NeuNAc. The molecular mimicry of the LOSs may play a role in the
pathogenesis of N.meningitidis by assisting the organism to evade host
immune defenses in man.
相似文献
16.
17.
Delfien Van Dyck Megan Teychenne Sarah A. McNaughton Ilse De Bourdeaudhuij Jo Salmon 《PloS one》2015,10(3)
Background
Mental health conditions are among the leading non-fatal diseases in middle-aged and older adults in Australia. Proximal and distal social environmental factors and physical environmental factors have been associated with mental health, but the underlying mechanisms explaining these associations remain unclear. The study objective was to examine the contribution of different types of physical activity in mediating the relationship of social and physical environmental factors with mental health-related quality of life in middle-aged and older adults.Methods
Baseline data from the Wellbeing, Eating and Exercise for a Long Life (WELL) study were used. WELL is a prospective cohort study, conducted in Victoria, Australia. Baseline data collection took place in 2010. In total, 3,965 middle-aged and older adults (55–65 years, 47.4% males) completed the SF-36 Health Survey, the International Physical Activity Questionnaire, and a questionnaire on socio-demographic, social and physical environmental attributes. Mediation analyses were conducted using the MacKinnon product-of-coefficients test.Results
Personal safety, the neighbourhood physical activity environment, social support for physical activity from family or friends, and neighbourhood social cohesion were positively associated with mental health-related quality of life. Active transportation and leisure-time physical activity mediated 32.9% of the association between social support for physical activity from family or friends and mental health-related quality of life. These physical activity behaviours also mediated 11.0%, 3.4% and 2.3% respectively, of the relationship between the neighbourhood physical activity environment, personal safety and neighbourhood social cohesion and mental health-related quality of life.Conclusions
If these results are replicated in future longitudinal studies, tailored interventions to improve mental health-related quality of life in middle-aged and older adults should use a combined strategy, focusing on increasing physical activity as well as social and physical environmental attributes. 相似文献18.
We investigated the role of the main olfactory and accessory olfactory systems (MOS and AOS respectively) in the detection of androstenone. We used the following experimental approaches: behavioral, surgical removal of the vomeronasal organ (VNX) followed by histochemical verification and Fos immunohistochemistry. Using a Y-maze paradigm we estimated sensitivity of NZB/B1NJ and CBA/J mice to androstenone. CBA mice were 2,000-fold more sensitive to androstenone than NZB mice. VNX caused a 4- to 16-fold decre... 相似文献
19.
Assessing and reporting heterogeneity in treatment effects in clinical trials: a proposal 总被引:1,自引:0,他引:1
David M Kent Peter M Rothwell John PA Ioannidis Doug G Altman Rodney A Hayward 《Trials》2010,11(1):1-11
Background
This paper presents the study protocol for a pragmatic randomised controlled trial to evaluate the impact of a school based program developed to prevent teenage pregnancy. The program includes students taking care of an Infant Simulator; despite growing popularity and an increasing global presence of such programs, there is no published evidence of their long-term impact. The aim of this trial is to evaluate the Virtual Infant Parenting (VIP) program by investigating pre-conceptual health and risk behaviours, teen pregnancy and the resultant birth outcomes, early child health and maternal health.Methods and Design
Fifty-seven schools (86% of 66 eligible secondary schools) in Perth, Australia were recruited to the clustered (by school) randomised trial, with even randomisation to the intervention and control arms. Between 2003 and 2006, the VIP program was administered to 1,267 participants in the intervention schools, while 1,567 participants in the non-intervention schools received standard curriculum. Participants were all female and aged between 13-15 years upon recruitment. Pre and post-intervention questionnaires measured short-term impact and participants are now being followed through their teenage years via data linkage to hospital medical records, abortion clinics and education records. Participants who have a live birth are interviewed by face-to-face interview. Kaplan-Meier survival analysis and proportional hazards regression will test for differences in pregnancy, birth and abortion rates during the teenage years between the study arms.Discussion
This protocol paper provides a detailed overview of the trial design as well as initial results in the form of participant flow. The authors describe the intervention and its delivery within the natural school setting and discuss the practical issues in the conduct of the trial, including recruitment. The trial is pragmatic and will directly inform those who provide Infant Simulator based programs in school settings.Trial registration
ISRCTN24952438 相似文献20.
Caroline PA de Haan Rauni I Kivistö Marjaana Hakkinen Jukka Corander Marja-Liisa Hänninen 《BMC microbiology》2010,10(1):200