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61.
Studied visual masking and visual integration across saccadic eye movements in 4 experiments. In a 5th experiment, 4 randomly chosen dots from a 3?×?5 dot matrix were presented in 1 fixation, and 4 different dots from the matrix were presented in a 2nd fixation. Ss reported the location of the missing dot. When the 1st display was presented just before the saccade (as in Exps I–III), Ss accurately specified the missing dot location when the dots were presented to the same region of the retina but not when they were presented in the same place in space. When the 1st display was presented well before the saccade (as in Exp IV), Ss performed poorly regardless of retinal or spatial overlap. Results indicate the existence of a short-lived retinotopic visual persistence but provide no support for a spatiotopic visual persistence capable of fusing the contents of successive fixations. It is concluded that transsaccadic integration depends instead on an abstract memory that accumulates position and identity information about the contents of successive fixations. Results are discussed in relation to the work by M. L. Davidson et al (see record 1974-10245-001). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
We employed an anatomically realistic three-dimensional finite-element model to explore several biomechanical variables involved in coring or bone-grafting of a segmentally necrotic femoral head. The mechanical efficacy of several variants of these procedures was indexed in terms of their alteration of the stress:strength ratio in at-risk necrotic cancellous bone. For coring alone, the associated structural compromise was generally modest, provided that the tract did not extend near the subchondral plate. Cortical bone-grafting was potentially of great structural benefit for femoral heads in which the graft penetrated deeply into the superocentral or lateral aspect of the lesion, ideally with abutment against the subchondral plate. By contrast, central or lateral grafts that stopped well short of the subchondral plate were contraindicated biomechanically because they caused marked elevations in stress on the necrotic cancellous bone. Calculated levels of stress were relatively insensitive to variations in the diameter of the graft. 相似文献
63.
64.
Mothers (N?=?76) of 3- to 5-year-old children completed questionnaires assessing beliefs in the importance and modifiability (vs. innateness) of children's peer relationship skills, perceptions of their children's social competence with peers, and strategies they would use in response to children's peer interaction problems. A subsample of mothers (n?=?34) was observed supervising the play of their own children and a peer. Maternal perceptions of children's competence were negatively associated with the extent of mothers' involvement in children's play, whereas the quality of supervision was predicted by knowledge of socialization strategies and the interaction of beliefs and knowledge. Beliefs appeared to moderate the effects of maternal knowledge on mothers' behavior in that knowledge was associated with the quality of supervision only when mothers believed social skills were important and modifiable. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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With the recent advent of accurate orbital volume assessment by computed tomography, a retrospective analysis was made of 31 patients with 'pure' blowout fracture of the orbital floor, managed either surgically or conservatively, to determine whether orbital volume measurement could provide an additional parameter of use in the management of such fractures. There was a significant difference in orbital volume discrepancy between patients managed surgically or conservatively suggesting that this investigation may be of use in decision making on surgical intervention in patients with orbital blowout fractures. 相似文献
67.
Mark T. Muldoon Dale V. Onisk Michael C. Brown & James W. Stave 《International Journal of Food Science & Technology》2004,39(8):851-861
Bovine spongiform encephalopathy (BSE), or ‘mad cow disease’, is one of several transmissable spongiform encephalopathies (TSEs) known to affect certain mammals and is spread through the ingestion of infected animal tissue. It is believed that the inadvertent contamination of meat and bone meal (MBM) with infected animal tissue and the subsequent use of this material as a feed supplement contributed to the spread of the disease in cattle. As a result, the use of processed animal proteins (PAPs) in animal feeds is regulated in many parts of the world. Although feed testing is the only definitive means to certify compliance, regulatory compliance often relies solely on paper certification. Recently, rapid methods have become available that can be used by regulators to determine compliance during routine inspections. We describe a rapid, immunochromatographic strip test that can detect 0.1% MBM in animal feed. The test takes 15 min to perform and large numbers of samples can be screened for PAPs simultaneously. 相似文献
68.
The modality effect in immediate recall refers to superior recall of the last few items within lists presented in spoken as opposed to printed form. The locus of this well-known effect has been unclear. N. Cowan, J. S. Saults, E. M. Elliott, and M. Moreno (2002) introduced a new method to distinguish between the effects of input serial position, output serial position, and the number of items yet to be recalled and found that large modality effects occurred only in conditions in which delay and interference at output (from items already recalled) was high. The authors replicated that finding, even when the response period included output interference acoustically similar to the spoken stimuli to be recalled. However, the authors found that output delay and interference act only by lowering the level of performance to a more sensitive range. The modality effect thus originates during encoding of the list to be recalled, not during output. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
M Brown M Webb E Phillips E Skidmore P McIntyre 《Canadian Metallurgical Quarterly》1995,73(7):780-786
We describe the results of functional studies on DNA clones encoding functional bradykinin receptors derived from human, rat, and mouse sources and including both genomic and complementary DNA clones. In both the Xenopus oocyte and the COS cell expression systems, the receptors from human and rat showed the pharmacological properties of B2 receptors, but receptors from mouse displayed both B1- and B2-like pharmacological properties. We further investigated the molecular relationship between the B1 and B2 receptor subtypes expressed by a human fibroblast cell line, and we demonstrate that these two receptor subtypes are encoded by distinct mRNA species. 相似文献
70.