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1.
3.
We report a case of cervical epidural hematoma associated with anticoagulant therapy in a 68 year-old man, who presented with tetraplegia. He was operated 12 hours after the onset. Three months later, he had recovered almost completely. The etiologies and prognosis of such lesions are reviewed. 相似文献
4.
Bob Eisenberg 《Journal of Computational Electronics》2002,1(3):331-333
Ion channels are proteins with a hole down their middle important in a wide range of biological functions yet simple enough to be analyzed as devices in the engineering tradition. 相似文献
5.
Mela P. Veltink P.H. Huijing P.A. Salmons S. Jarvis J.C. 《IEEE transactions on neural systems and rehabilitation engineering》2002,10(2):85-93
Stimulation patterns can be optimized by maximizing the force-time integral (FTI) per stimulation pulse of the elicited muscle contraction. Such patterns, providing the desired force output with the minimum number of pulses, may reduce muscle fatigue, which has been shown to correlate to the number of pulses delivered. Applications of electrical stimulation to use muscle as a controllable biological actuator may, therefore, be improved. Although muscle operates over a range of lengths, optimized patterns have been determined only at optimal muscle length. In this study, the patterns with up to four pulses that produced the highest isometric FTI were determined at 10 muscle lengths for 11 rabbit tibialis anterior muscles. The interpulse intervals (IPIs) used ranged from 4 to 54 ms. At high muscle length, the optimal stimulation pattern consisted of an initial short IPI (doublet) followed by longer IPIs, in agreement with previous studies. However, at low length, the third pulse still elicited more than linear summation (triplet); furthermore, the relative enhancement of the FTI per pulse was considerably larger at low length than at high length, suggesting that optimal stimulation patterns are length dependent. 相似文献
6.
M. J. Jarvis 《Tobacco control》1994,3(4):324-328
7.
This paper provides a postcolonial policy analysis of the Education Sector Development Plan: 2000-2005 and Beyond in the small Caribbean island nation of St Lucia. The specific focus is upon the nature of the lifelong learning policy as incorporated in the Plan. This is shown to be a globalised policy discourse. Drawing on a number of postcolonial theorists, the paper works with a concept of the postcolonial as an aspirational politics. Bourdieu's concept of 'national capital' is also utilised in the analysis in relation to the attempt to manage some autonomy for the nation in the process of policy text production in education. The analysis demonstrates the way a postcolonial politics, manifest as strengthening national capital, worked in relation to the production of the Plan in its consultative mode of production and in its extensive cross-sector coverage. However, the analysis also shows evidence of the effects of residues of the colonial past in the hegemony of English in the Plan's recommendations, in the restriction of lifelong learning facilitation to schools and in the denial of a place for indigenous knowledges. The mode of lifelong learning supported is also dominated by a human capital framework and neglect of other capitals (social, cultural, etc.) for constituting what might be seen as a postcolonial and creole learning society. The paper also reflects upon the extent of the postcoloniality of the analysis provided. 相似文献
8.
The failure of acetabular cups via loosening, migration or fracture is partially related to the stress distribution existing in the acetabular region. The complexity of the investigation of these stresses demands the application of a variety of model testing techniques involving combined embedded strain gauging, finite element analysis, transmission and reflective photoelasticity and crack propagation studies. The application of these procedures are described and the difficulties of obtaining representative loadings and restraints are commented upon. 相似文献
9.
Bellovin Steven M. Benzel Terry V. Blakley Bob Denning Dorothy E. Diffie Whitfield Epstein Jeremy Verissimo Paulo 《Security & Privacy, IEEE》2008,6(1):16-23
A virtual roundtable (featuring panelists Steven Bellovin, Terry Benzel, Bob Blakely, Dorothy Denning, Whitfield Diffie, Jeremy Epstein, and Paulo Verissimo) discussing the next 15 years in computer security. 相似文献
10.
回首过去,我们发现在RFID的发展方面,2006年已经成为"一方面与另一方面"的一年. 相似文献