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591.
ABSTRACT

In the Balkans, contact with gays and lesbians is typically hostile or avoided. Drawing from probability samples of young people from five Balkan countries (N = 1046), we examined whether it is possible to transfer the effects of contact with other marginalized outgroups (largest ethnic minority in every country, Roma, the extremely poor and physically disabled) to acceptance of gays and lesbians (secondary outgroup), and whether this relationship could be explained by attitude generalization and increased intergroup trust. Path analyses supported the secondary transfer effect: it confirmed that, while controlling for direct contact, contact with other marginalized groups was related to more acceptance of a secondary group; this relationship was mediated by trust. This was found across all primary groups in the combined samples, while the effect varied for different groups in country samples. The results add to the value of intergroup contact as a mean of prejudice-reduction.  相似文献   
592.
The predictive validity of the EPQ scales with regard to future offending was examined. The Junior and Adult EPQ forms were administered to 179 male high-school students (13–15 yrs) and 75 delinquent youths (15–18 yrs), respectively. All subjects were followed up with regard to proven offences committed in the 12-month period following testing. The results suggested that both the junior and adult form P and C scales have validity in predicting future offending.  相似文献   
593.
Husserl on Hume     
ABSTRACT

This article offers an account of the development of Husserl’s assessment of Hume’s position in the history of philosophy. In Husserl’s early treatment of Hume, Husserl’s interpretation was shaped by the anti-Kantian views of his teacher Franz Brentano. Later, however, Husserl concentrated on those themes in Hume’s philosophy that were of relevance for the development of his own conception of phenomenology. His analysis into the a priori structures of intentionality led the Husserl of Logical Investigations (1900–1901) to reject Hume’s nominalism and sensualism, and to criticize Hume’s naturalistic psychologism and fictionalism. Already at this point, however, Husserl appreciated Hume’s metaphysical neutrality as well as his radical starting point in the immediate givenness of consciousness. In the period following Husserl’s transcendental turn in Ideas I (1913), Hume is gradually re-assessed in the context of Husserl’s engagement with Kant as a philosopher who offers important insights concerning concrete problems of transcendental philosophy. For Husserl, Hume ultimately offers the first outline of a pure phenomenology and, indeed, becomes one of the most important forerunners of transcendental philosophy as such.  相似文献   
594.
Discrimination of sensory signals is essential for an organism to form and retrieve memories of relevance in a given behavioral context. Sensory representations are modified dynamically by changes in behavioral state, facilitating context-dependent selection of behavior, through signals carried by noradrenergic input in mammals, or octopamine (OA) in insects. To understand the circuit mechanisms of this signaling, we characterized the function of two OA neurons, sVUM1 neurons, that originate in the subesophageal zone (SEZ) and target the input region of the memory center, the mushroom body (MB) calyx, in larval Drosophila. We found that sVUM1 neurons target multiple neurons, including olfactory projection neurons (PNs), the inhibitory neuron APL, and a pair of extrinsic output neurons, but relatively few mushroom body intrinsic neurons, Kenyon cells. PN terminals carried the OA receptor Oamb, a Drosophila α1-adrenergic receptor ortholog. Using an odor discrimination learning paradigm, we showed that optogenetic activation of OA neurons compromised discrimination of similar odors but not learning ability. Our results suggest that sVUM1 neurons modify odor representations via multiple extrinsic inputs at the sensory input area to the MB olfactory learning circuit.

Behavioral choices depend on discrimination among “sensory objects,” which are neural representations of multiple coincident sensory inputs, across a range of sensory modalities. For example, “odor objects” (Gottfried 2009; Wilson and Sullivan 2011; Gire et al. 2013) are represented in sparse ensembles of neurons, that are coincidence detectors of multiple parallel inputs from odor quality channels. This principle is used widely in animals, including in mushroom bodies (MBs), the insect center for associative memory (Masuda-Nakagawa et al. 2005; Honegger et al. 2011), and in the piriform cortex (PCx) of mammals (Stettler and Axel 2009; Davison and Ehlers 2011).The selectivity of sensory representations can be modulated dynamically by changes in behavioral state, allowing an animal to learn and respond according to perceptual task. In mammals, the noradrenergic system originating in the locus coeruleus (LC) is implicated in signaling behavioral states such as attention, arousal and expectation (Aston-Jones and Cohen 2005; Sara and Bouret 2012).In insects, octopamine (OA), structurally and functionally similar to noradrenalin (NA) in mammals (Roeder 2005), can mediate changes in behavioral state that often promote activity; for example, sensitization of reflex actions in locusts (Sombati and Hoyle 1984), aggressive state in crickets (Stevenson et al. 2005), initiation and maintenance of flight state (Brembs et al. 2007; Suver et al. 2012), and enhanced excitability of Drosophila motion detection neurons during flight (Strother et al. 2018). Another role of OA is as a reward signal: A single OA neuron, VUMmx1, mediates the reinforcing function of unconditioned stimulus in the honeybee proboscis extension reflex (Hammer 1993; Hammer and Menzel 1998; Menzel 2012). In Drosophila, acquisition of appetitive memory is impaired in TβH mutants, unable to synthesize OA (Schwaerzel et al. 2003), and activation of OA neurons can substitute reinforcing stimulus in appetitive learning (Schroll et al. 2006). Moreover, OA receptors are necessary for reward learning in Drosophila (Burke et al. 2012) and crickets (Matsumoto et al. 2015).To understand the neural mechanisms of OA in higher order sensory discrimination, we used the simple sensory “cortex” of larval Drosophila, the calyx, which is the sensory input region of the mushroom bodies (MBs), the insect memory center. Here, each MB neuron (Kenyon cell [KC]) typically arborizes in several glomeruli, most of which are organized around the terminus of an olfactory projection neuron (PN); KCs thus combinatorially integrate multiple sensory input channels (Masuda-Nakagawa et al. 2005) and are coincidence detectors of multiple inputs. The APL provides inhibitory feedback (Lin et al. 2014; Masuda-Nakagawa et al. 2014) and helps to maintain KC sparse responses and odor selectivity (Honegger et al. 2011), analogous to inhibition in the mammalian PCx (Poo and Isaacson 2009; Stettler and Axel 2009; Gire et al. 2013). Thus, odors are represented as a sparse ensemble of KCs that are highly odor selective, a property beneficial for memory (Olshausen and Field 2004).In addition, the larval MB calyx is innervated by two OA neurons, sVUMmd1 and sVUMmx1, ventral unpaired medial neurons with dendritic fields originating in the mandibular and maxillary neuromeres, respectively, of the SEZ in the third instar larva (Selcho et al. 2014). sVUMmd1 and sVUMmx1 are named as OANa-1 and OANa-2, respectively, in the EM connectomic analysis of a 6-h first instar larva (Eichler et al. 2017; Supplemental Fig. 3 of Saumweber et al. 2018). These sVUM1 neurons also innervate the first olfactory neuropile of the antennal lobe (AL). This pattern of innervation is conserved in other insects, for example, the dorsal unpaired median (DUM) neurons in locusts (for review, see Bräunig and Pflüger 2001), the VUMmx1 neuron in honeybees (Hammer 1993; Schröter et al. 2007), and OA-VUMa2 neurons in adult Drosophila (Busch et al. 2009). In adult Drosophila, OA-VUMa2 neurons also show a dense innervation of the lateral horn, implicated in innate behaviors (Busch et al. 2009). The widespread innervation of the insect olfactory neuropiles also resembles the widespread NA innervation of mammalian olfactory processing areas, such as the olfactory bulb, and piriform cortex, by LC neurons originating in the brainstem.We characterized the innervation pattern and synaptic targets of sVUM1 neurons in the calyx, with MB intrinsic and also extrinsic neurons, the localization of the OA receptor Oamb in the calyx circuit, and the impact of sVUM1 neuron activation on behavioral odor discrimination. For this we used an appetitive conditioning paradigm, and tested the ability of larvae to discriminate between similar odors, as opposed to dissimilar odors. Since the larval connectome is based on a single brain, at first instar stage before octopaminergic connections have become as extensive as at third instar, and to obtain a comprehensive understanding of the synaptic targets of sVUM1s in the third-instar larval calyx, we extended our analysis to previously unanalyzed connectivity of VUM1s, to APL and PNs. Further, we combined light microscopy of third-instar larvae with the connectome described by Eichler et al. (2017).We find that sVUM1 neurons in third-instar larvae contact all the major classes of calyx neuron to some degree, consistent with EM synaptic analysis of the 6-h larva (Eichler et al. 2017). A GFP fusion of the OA receptor Oamb is localized in the terminals of PNs, and activating a subset of five SEZ neurons, including sVUM1 neurons, can affect discrimination of similar odors, without affecting underlying olfactory learning and memory ability. We suggest a broad modulatory effect of sVUM1 neurons in the calyx, including a potential role in modulating PN input at the second synapse in the olfactory pathway.  相似文献   
595.
596.
明末西方传教士出于抬高西方宗教、传播宗教福音的政治考量,翻译出版了大量的西方科学著作.西方演绎逻辑思想正是在这样的背景下,得以在明末被翻译介绍到国内.这其中,尤以利玛窦推动译介的<几何原本>及傅汎际推动译介的<名理探>最为知名.这其中,自然也毫无例外地带有浓厚的为宗教传道先行的色彩.但也在客观上帮助了中国人了解西方演绎逻辑的思想,带动了其后国内学界对挖掘本土以名辩学为基础的中国逻辑史研究的热潮.  相似文献   
597.
The aim of this study was to explore genetic and environmental contributions to laboratory-induced aggressive behavior. On a sample of 478 adult twins (316 monozygotic), the Competitive Reaction Time Task was used for aggression induction. The results showed that the initial, basic level of aggression could be explained by both shared (45%) and nonshared environmental factors (55%), while only nonshared environmental factors (100%) had a significant influence on changes in aggression as provocation increased. Genetic factors had no influence on laboratory-induced aggression. The results highlight the importance of environmental factors in shaping situation-specific aggressive responses to provocation.  相似文献   
598.
599.
600.
Tryptophan hydroxylase 1 (TPH1) gene, coding for serotonin synthesizing enzyme, and recent stressful life events (SLEs) have been commonly associated with suicidal behavior. TPH1 has been also hypothesized to be involved in stress–response mechanisms. The aim of this study was to assess TPH1 variant rs1800532 and its possible interaction with recent SLEs as risk factors for suicide attempt (SA) in Serbian psychiatric patients, including 165 suicide attempters and 188 suicide nonattempters. rs1800532 and recent SLEs were independently associated with SA, while rs1800532 did not moderate the effect of recent SLEs on SA vulnerability among Serbian psychiatric patients.  相似文献   
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