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Stephan Fricke Nadja Hilger Christian Fricke Uta Schönfelder Gerhard Behre Peter Ruschpler Andreas Boldt Christopher Oelkrug Ulrich Sack Frank Emmrich 《Cellular and molecular life sciences : CMLS》2014,71(11):2135-2148
This is the first report showing that an epitope-specific ex vivo modulation of an allogeneic hematopoietic stem cell graft by the anti-human CD4 antibody MAX.16H5 IgG1 simultaneously facilitates the anti-tumor capacity of the graft (Graft-versus-leukemia effect, GvL) and the long-term suppression of the deleterious side effect Graft-versus-host-disease (GvHD). To distinguish and consolidate GvL from GvHD, the anti-human CD4 antibody MAX16.H5 IgG1 was tested in murine GvHD and tumor models. The survival rate was significantly increased in recipients receiving a MAX.16H5 IgG1 short-term (2 h) pre-incubated graft even when tumor cells were co-transplanted or when recipient mice were treated by MAX.16H5 IgG1 before transplantation. After engraftment, regulatory T-cells are generated only supporting the GvL effect. It was also possible to transfer the immune tolerance from GvHD-free recipient chimeras into third party recipient mice without the need of reapplication of MAX.16H5 IgG1 anti-human CD4 antibodies. These findings are also benefical for patients with leukemia when no matched related or unrelated donor is available and provides a safer allogeneic HSCT, which is more effective against leukemia. It also facilitates allogeneic (stem) cell transplantations for other indications (e.g., autoimmune-disorders). 相似文献
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Nikolai Axmacher Andreas Draguhn Christian E. Elger Juergen Fell 《Cellular and molecular life sciences : CMLS》2009,66(14):2285-2297
Two-step theories of memory formation suggest that an initial encoding stage, during which transient neural assemblies are
formed in the hippocampus, is followed by a second step called consolidation, which involves re-processing of activity patterns
and is associated with an increasing involvement of the neocortex. Several studies in human subjects as well as in animals
suggest that memory consolidation occurs predominantly during sleep (standard consolidation model). Alternatively, it has
been suggested that consolidation may occur during waking state as well and that the role of sleep is rather to restore encoding
capabilities of synaptic connections (synaptic downscaling theory). Here, we review the experimental evidence favoring and
challenging these two views and suggest an integrative model of memory consolidation. 相似文献
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Solana Abraham Christian Rodríguez Andrea Oviedo Gabriela Murúa 《Journal of Natural History》2018,52(23-24):1493-1508
While expulsion of male ejaculates by the females after copulation has been reported for various animal groups, expulsion followed by consumption of the expelled ejaculate is a rare behaviour outside spermatophylax-producing orthopterans. Among Diptera, this behaviour has been reported for a few species of Piophilidae, Empididae and Ulidiidae. Here we report on its occurrence among Euxesta eluta and Euxesta mazorca (Diptera: Ulidiidae). We also attempt to characterize the mating system of E. eluta in order to facilitate future hypothesis testing to understand the behavioural factors leading to the evolution of this peculiar behaviour. For this, courtship sequences, copulation duration, frequency of ejaculate expulsion and subsequent consumption, and latency to ejaculate expulsion for both E. eluta and E. mazorca were recorded. The time of sexual maturation, the time window of sexual receptivity during the day, and the mating frequency and variance in mating success for males and females (degree of polygamy) were determined for E. eluta. Both E. eluta and E. mazorca males engaged in elaborate courtship sequences involving visual and tactile displays before copulation. Females of both species almost invariably expelled and consumed ejaculates after copulation. Female E. eluta, required a 6- to 9-day period feeding on protein and sugar before becoming sexually receptive. Reproductive activity occurred continuously over the day with an early morning and late afternoon peak. Both males and females could mate multiply, with multiple partners over a 2-h observational period. Sexual network analysis revealed that some males and females had greater mating success than others. Ejaculate consumption appears to be widespread in the genus Euxesta. It is possible that females obtain nutrients from this behaviour while exerting some control over egg fertilization. 相似文献
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Résumé Nous montrons que Poincaré, dans son article de 1905, adopte un point de vue actif concernant le groupe des Transformations
de Lorentz. Ce point de vue, selon lequel les transformations agissent directement sur les systèmes physiques (sans toucher
au système de coordonnées), est naturel pour lui car il est celui des géomètres et aussi implicitement celui de Lorentz dans
son traitement mathématique des états correspondants. L'adoption de ce point de vue est même nécessaire pour corriger l'?
erreur ? de Lorentz dans sa définition d'un système globalement en mouvement. La contraction des longueurs, comme la dilatation
des temps, traditionnellement attachées aux changements de référentiels, trouvent également une explication physique relativiste
dans cette approche.
Présenté par J. D. Norton (Manuscrit re?u le 29 juillet 2005) Publication éléctronique le 14 mars 2006 相似文献
Présenté par J. D. Norton (Manuscrit re?u le 29 juillet 2005) Publication éléctronique le 14 mars 2006 相似文献
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Structuration Theory and Self-Organization 总被引:2,自引:2,他引:0
Social systems theory is dominated by a reductionistic individualism and a dualistic functionalism. Especially the latter does not, adequately integrate the human being. In order to avoid dualism, mechanistic determinism, and reductionism, a dialectical concept of social systems that is based on the notion of self-organization seems necessary. In order to establish a dialectical theory of social self-organization it is appropriate to integrate aspects of Anthony Giddens' structuration theory. Giddens acknowledges the importance of knowledgeable human actors in society and argues that structures are the medium and outcome of actions (theorem of the duality of structure). Structures both enable and constrain social actions. This idea corresponds to saying that social systems are re-creative, i.e., self-organizing social systems. Re-creativity is based on the creative activities of human beings. Social structures exist in and through the productive practices and relationships of human actors. The term evolution can be employed in a nonfunctionalist way that acknowledges the importance of knowledgeable human actors in social systems by conceiving the historical development of society based on a dialectic of chance and necessity and theprinciple of order through fluctuation in situations of instability and bifurcation. All self-organizing systems are information-generating systems. Giddens' concept of storage mechanisms that allow time–space distanciation of social relationships helps to describe the relationship of information and self-organization in social systems. 相似文献
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