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排序方式: 共有5015条查询结果,搜索用时 15 毫秒
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JR Kerr D Kane B Crowley N Leonard S O''Briain PV Coyle F Mulcahy 《Canadian Metallurgical Quarterly》1997,8(3):184-186
We report a 16-year-old boy, born to consanguineous parents, with mental retardation, gait disturbances and dysarthria; brain magnetic resonance showed features consistent with rhombencephalosynapsis. This condition is characterised by a hypoplastic single-lobed cerebellum. The interest of this case is the presence of common ancestors, pointing to an autosomal recessive inheritance of the malformation. 相似文献
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Low temperature heat capacity measurements have been made on hot isostatically pressed Nb3Sn and arc cast, homogenized, and A15 transformation annealed V-23.3 at. pct Ga and V-18.1 at. pct Ga. The heat capacity measurements
display the superconducting transition temperature (T
c), and have been used to evaluate the effects of plastic deformation on theT
c range. Plastic deformation to the extent of 15 pct compression at 1525 and 1650 °C does not alter the superconducting transition
in polycrystalline Nb3Sn. Plastic deformation to the extent of 15 pct compression at 1050 and 1200 °C does not alter the superconducting transition
in polycrystalline V-23.3Ga, transformed to A15 structure with a fifty-hour 1150 °C anneal. The same statement can be made
for A15 V-18.1Ga, deformed at 1050 °C after a fifty-hour, 1150 °C anneal. With onlyfive hours annealing at 1150 °C, A15 V-23.2Ga displays a lowering and broadening of theT
c range upon 1050 and 1200 °C plastic deformation. With onlyfive hours annealing at 1150 °C, A15 V-18.1Ga displays a broad, but increasedT
c range after plastic deformation at 1050 °C. 相似文献
37.
Toshiaki Nishihata Mayumi Ishizaka Sigeharu Yokohama Alice C. Martino Roger E. Gordon 《Drug development and industrial pharmacy》1993,19(20):2679-2698
The effects of particle size and food on the absolute bioavailability of U-78875 in dogs after oral administration of either a suspension or tablet dosage form were investigated. A reduction of particle size caused a significant increase in bioavailability along with an increase in dissolution rate. Additionally, both suspension and tablet dosage forms administered after food caused an increase in bioavailability. Thus, to accelerate drug dissolution, a reduction of U-78875 particle size from the unmilled state is important for the optimization of formulation compositions. To increase the bioavailability of U-78875, postprandial dosing should be considered. 相似文献
38.
In 3 eye-tracking experiments, the authors investigated the use of morphological information during pronoun resolution. Experiments 1 and 2 showed that disruption occurred when a preferred assignment was inconsistent with gender information. Experiment 2 ensured that this difficulty was not due to the introduction of a new discourse entity. Experiment 3 showed that disruption also occurred when number information was inconsistent with the preferred assignment. The results indicate that the use of morphological information is delayed until after the computation of coreference relations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
39.
MacDonald Stuart W. S.; Hultsch David F.; Dixon Roger A. 《Canadian Metallurgical Quarterly》2003,18(3):510
Performance variability across repeated task administrations may be an important indicator of age-related cognitive functioning. In the present investigation, the authors examined whether age differences and change in inconsistency were related to 6-year (3 occasion) cognitive change. Inconsistency scores were computed from 4 reaction time tasks performed by 446 older adults (54-89 years). Replicating previous cross-sectional results, greater inconsistency was observed for older participants even after controlling for differences in response speed. New longitudinal results demonstrated (a) associations between inconsistency at baseline measurement and 6-year change in cognitive performance; (b) longitudinal change in inconsistency; and (c) intraindividual covariation between 6-year change in inconsistency and 6-year change in level of cognitive function. These findings support the view that performance variability serves as a marker of cognitive aging. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
40.
Roger M. Cooke 《Reliability Engineering & System Safety》1996,51(2):209-223
Models for analyzing dependent competing risk data are presented. These models are designed to represent interactions of critical failure and maintenance mechanisms responsible for intercepting incipient and degraded failures, and they are fashioned such that the (constant) critical failure rate is identifiable from dependent competing risk data. Uncertainty bounds for the critical failure rate which take modeling uncertainty and statistical fluctuations into account are given. 相似文献