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Tang Helen H. Y.; McNally Gavan P.; Richardson Rick 《Canadian Metallurgical Quarterly》2007,121(6):1421
The authors studied the role of gamma-aminobutyric acid (GABA) in 2 types of forgetting of fear in the developing rat. One type of forgetting studied was that observed after an intermediate retention interval (the "Kamin effect"); the other type studied was that observed after a longer interval (infantile amnesia). Rats were given pairings of an auditory conditioned stimulus with shock, and learned fear was assessed by freezing. Forgetting at an intermediate retention interval (1 hr) was not alleviated by the GABAA receptor partial inverse agonist FG7142 (0, 1, 5, or 10 mg/kg), whereas forgetting at a longer retention interval (48 hr) was alleviated. These results suggest that in the developing rat, forgetting observed at different retention intervals is mediated by different physiological mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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van Baaren Rick B.; Maddux William W.; Chartrand Tanya L.; de Bouter Cris; van Knippenberg Ad 《Canadian Metallurgical Quarterly》2003,84(5):1093
The present studies demonstrated the moderation of self-construal orientation on mimicry. Recent research has indicated that an interdependent self-construal is associated with assimilation of the other to the self whereas an independent self-construal is associated with minimizing the influence of others on the self (H. R. Markus & S. Kitayama, 1991; D. Stapel & W. Koomen, 2001). Therefore, the authors hypothesized that an interdependent self-construal would be associated with more mimicry than an independent self-construal. When self-construal orientations were experimentally primed. as in Studies 1 and 2, independent self-construals produced less nonconscious mimicry than interdependent self-construals. When self-construals were examined as cultural differences with either a chronically dominant independent (Americans) or interdependent (Japanese) construal of the self, these results were replicated. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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eCRM (electronic Customer Relationship Management) systems focus on using the web-site as the main interaction channel for businesses to simulate an old fashioned one-to-one direct relationship—high touch—with customers. In this research two distinct but related concepts, media richness from the Human Computer Interaction and Computer Mediated Communication fields and perceived interactivity from the Marketing and MIS fields, are disentangled and their unique impacts on technology acceptance variables are examined in the eCRM Acceptance Model. The present study contributes in extending the Technology Acceptance Model for the eCRM context and in establishing media richness and perceived interactivity as antecedents to perceived usefulness and perceived ease of use. Our research model integrates system perception (e.g., perceived usefulness and perceived ease of use) and subjective outcome measures (e.g., decision satisfaction) in a single model to fully understand the impact of eCRM “touch” design perceived by e-customers on their intention to return after the initial visit. An experimental survey of two culture groups (independent vs. interdependent self-construal) of technology savvy, young college students reveals that culture value-orientation (e.g., self-construal) moderates the effect of decision satisfaction on behavior intention to return in our eCRM Acceptance model. Findings of this research thus have significant theoretical and managerial implications. 相似文献
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O Rick HG Heuft G Wittmann R Blasczyk D Huhn N Schwella 《Canadian Metallurgical Quarterly》1997,12(4):179-182
The heterocomplex of glycoproteins E and NS1 of tick-borne encephalitis (TBE) virus was isolated from culture fluid of continuous SPEV (porcine embryo kidney) cells by affinity chromatography on CL4B sepharose with immobilized monoclonal antibodies to TBE virus protein NS1. Comparison of the TBE E-NS1 heterocomplex from culture fluid and cells showed the predominance of secreted extracellular form. A similar TBE virus heterocomplex E-NS1 was revealed in the blood sera of patients with TBE but not in their lymphocytes. Extracellular localization of the E-NS1 complex at the late stage of infection rules out its hypothesized participation in the replication of TBE virus. Virtual absence of the heterocomplex and presence of proteins E and NS1 in high concentrations in the cells makes the nonspecific aggregation of these proteins impossible. Evidently, the extracellular heterocomplex E-NS1 may react with virusspecific antibodies or with cytotoxic T lymphocytes. 相似文献
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Recently published studies indicate a potential clinical application of PET in head and neck tumors. In the preoperative staging phase, PET enables confirmation of regional lymph node extension and guides nodal neck dissection or systemic treatment. In this phase, a high negative predictive value, near 100%, could make it possible to avoid many negative neck dissections. This is a reliable technique for confirming or excluding the presence of recurrent/residual tumor and for obtaining an early evaluation of chemotherapeutic and radiotherapeutic response. PET imaging in many cases makes it possible to locate and guide histological study of tumors with an unknown primary. PET imaging for these indications is a perfect complementary method for clinical exploration and better than other imaging techniques. 相似文献
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PD Darney 《Canadian Metallurgical Quarterly》1996,14(1):51-61
The abundance of rapid eye movement (REM) sleep in the neonatal mammal and its subsequent decline in the course of development, as well as the dramatic and widespread enhancement of CNS activity during REM sleep, led us to propose that this state plays a functional role in the normative physiological and structural maturation of the brain [54]. When, after 1 week of monocular deprivation (MD), a second week of MD was coupled with behavioral deprivation of REM sleep, the structural alteration in the visual system provoked by MD alone (interlaminar relay cell-size disparity in the lateral geniculate nucleus (LGN) was amplified. With the addition of REM deprivation during MD, the LGN cells connected to the surgically patched eye, which are smaller than normal after MD, became even smaller, whereas the LGN cells receiving input from the seeing eye, which display compensatory hypertrophy after MD, grew even larger. We believe that the interlaminar disparity effect widened because during REM deprivation, the already vision-compromised LGN cells associated with the patched eye also lose the ascending brainstem activation reaching them during the REM state. Loss of the two main sources of 'afference' by these LGN cells permits their seeing-eye LGN counterparts to gain even greater advantage in the competition for synaptic connections in cortex, which is reflected in the relative soma sizes of the LGN relay cells. It is likely that the relatively abundant REM state in early maturation provides symmetric stimulation to all LGN relay cells, irrespective of eye of innervation. The symmetric activation propagated from brainstem to LGN acts to 'buffer' abnormal, asymmetric visual input and, thereby diminishes the extreme, asymmetric structural alteration that results from MD in the absence of REM sleep. We conclude that REM sleep-generated CNS discharge in development has the effect of 'protecting' the CNS against excessive plasticity changes. This is consistent with the possibility that REM sleep plays a role in the genetically programmed processes that direct normative brain development. 相似文献