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The neural processes underlying empathy are a subject of intense interest within the social neurosciences. However, very little is known about how brain empathic responses are modulated by the affective link between individuals. We show here that empathic responses are modulated by learned preferences, a result consistent with economic models of social preferences. We engaged male and female volunteers in an economic game, in which two confederates played fairly or unfairly, and then measured brain activity with functional magnetic resonance imaging while these same volunteers observed the confederates receiving pain. Both sexes exhibited empathy-related activation in pain-related brain areas (fronto-insular and anterior cingulate cortices) towards fair players. However, these empathy-related responses were significantly reduced in males when observing an unfair person receiving pain. This effect was accompanied by increased activation in reward-related areas, correlated with an expressed desire for revenge. We conclude that in men (at least) empathic responses are shaped by valuation of other people's social behaviour, such that they empathize with fair opponents while favouring the physical punishment of unfair opponents, a finding that echoes recent evidence for altruistic punishment. 相似文献
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It has been 15 years since we proposed the defective ribosomal product (DRiP) hypothesis to explain the rapid presentation
of viral peptides by MHC class I molecules on the surface of infected cells. Here, we review the evidence for the contribution
of DRiPs to antigen processing, pointing to the uncertainties regarding the physical nature of DRiPs, and emphasizing recent
findings suggesting that peptide generation is a specialized process involving compartmentalized translation. 相似文献
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O. Palumbo F. Trequattrini N. Pal M. Hulyalkar S. Sarker D. Chandr T. Flanagan M. Dolan A. Paolone 《自然科学进展(英文版)》2017,27(1):126-131
Ni based amorphous materials have great potential as hydrogen purification membranes. In the present work the melt spun(Ni_(0.6)Nb_(0.4-y)Ta_y)_(100-x)Zr_x with y=0, 0.1 and x=20, 30 was studied. The result of X-ray diffraction spectra of the ribbons showed an amorphous nature of the alloys. Heating these ribbons below T 400 °C, even in a hydrogen atmosphere(1-10 bar), the amorphous structure was retained. The crystallization process was characterized by differential thermal analysis and the activation energy of such process was obtained. The hydrogen absorption properties of the samples in their amorphous state were studied by the volumetric method,and the results showed that the addition of Ta did not significantly influence the absorption properties, a clear change of the hydrogen solubility was observed with the variation of the Zr content. The values of the hydrogenation enthalpy changed from ~37 k J/mol for x=30 to ~9 k J/mol for x=20. The analysis of the volumetric data provides the indications about the hydrogen occupation sites during hydrogenation, suggesting that at the beginning of the absorption process the deepest energy levels are occupied, while only shallower energy levels are available at higher hydrogen content, with the available interstitial sites forming a continuum of energy levels. 相似文献
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In East and Central Africa the protozoan parasite Theileria parva causes a disease of cattle called East Coast fever (ECF). In Kenya alone between 60,000 and 85,000 cattle die from ECF every year. Infected animals can recover from ECF either naturally or after treatment with tetracyclines or menoctone and are subsequently able to resist challenge with the homologous strain of parasite. That this acquired resistance is due to cell-mediated rather than humoral immunity has been suspected but never decisively shown. A major difficulty in studying immunity to ECF has been the lack of inbred animals for studying Theileria-specific immunity in the absence of allogeneic histocompatibility barriers. We have avoided this problem by measuring cell-mediated immune responses in a syngeneic system in vitro. Unidirectional mixed lymphocyte cultures (MLC) were set up using bovine peripheral blood lymphocytes (PBL) as responder cells and autologous cell lines transformed in vitro by T. parva as stimulator cells. In these cultures, DNA synthesis was induced in PBL from both normal and Theileria-immune animals. However, cytotoxic lymphocytes were induced only in cultures containing responder lymphocytes from Theileria-immune cattle. The results show that Theileria-transformed cells express antigens which are recognized by effector cells and provide evidence that cell-mediated cytotoxic mechanisms function in immunity to ECF. 相似文献
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Ioannidis JP Gwinn M Little J Higgins JP Bernstein JL Boffetta P Bondy M Bray MS Brenchley PE Buffler PA Casas JP Chokkalingam A Danesh J Smith GD Dolan S Duncan R Gruis NA Hartge P Hashibe M Hunter DJ Jarvelin MR Malmer B Maraganore DM Newton-Bishop JA O'Brien TR Petersen G Riboli E Salanti G Seminara D Smeeth L Taioli E Timpson N Uitterlinden AG Vineis P Wareham N Winn DM Zimmern R Khoury MJ;Human Genome Epidemiology Network the Network of Investigator Networks 《Nature genetics》2006,38(1):3-5
Networks of investigators have begun sharing best practices, tools and methods for analysis of associations between genetic variation and common diseases. A Network of Investigator Networks has been set up to drive the process, sponsored by the Human Genome Epidemiology Network. A workshop is planned to develop consensus guidelines for reporting results of genetic association studies. Published literature databases will be integrated, and unpublished data, including 'negative' studies, will be captured by online journals and through investigator networks. Systematic reviews will be expanded to include more meta-analyses of individual-level data and prospective meta-analyses. Field synopses will offer regularly updated overviews. 相似文献
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The functional anatomy of memory 总被引:2,自引:0,他引:2
P. C. Fletcher R. J. Dolan C. D. Frith 《Cellular and molecular life sciences : CMLS》1995,51(12):1197-1207
A review of recent work using Positron Emission Tomography (PET) to examine brain systems involved in auditory-verbal memory is presented. Initial work delineated widespread brain regions which were, to a large extent, in agreement with existing neuropsychological literature. Expanding on this, a number of studies have examined memory encoding and retrieval separately. Additionally, experiments have been carried out to specifically address sub-components of memory such as the use of visual imagery as a mnemonic strategy, the functional anatomical evidence for the episodic/semantic memory distinction and the different brain regions involved in explicit and implicit memory tasks. 相似文献
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