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991.
LD Kniazeva ES Ketuladze SA Lipkovich NN Zhilina VM Stakhanova 《Canadian Metallurgical Quarterly》1976,16(5):51-55
A method developed by the authors is described that consists in a quantitative test for the evaluation of the reactivity of the microvessels judging by the degree of changes in the resorption speed of isotopes from a tissue depot. In patients with essential hypertension an increased vascular reactivity was revealed with reference to angiotensin, noradrenalin and serotonin, as well as an increased duration of the effect of angiotensin. The highest vascular reactivity was noted in patients with stage II hypertension who have retained a hyperkinetic type of circulation. 相似文献
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The silent period in the agonist prior to rapid voluntary movement (premotion silent period) was observed in the lower limb muscles. The subject was asked to respond to the flashing light by performing a vertical jump as quickly as possible. The most consistent results were obtained in the extensors, particularly the quadriceps. The frequency of the silence of six subjects was 53% in the rectus femoris, 61% in the vastus medialis, and 72% in the vastus lateralis. A neural switching mechanism, directing excitation from preparation phase of jumping into rapid contraction phase, seemed to be attributable to the occurrence of the premotion silent period. 相似文献
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Silvio Ghilardi 《Journal of Automated Reasoning》2004,33(3-4):221-249
We extend the Nelson–Oppen combination procedure to the case of theories that are compatible with respect to a common subtheory in the shared signature. The notion of compatibility relies on model completions and related concepts from classical model theory. 相似文献
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Frequency lowering is a form of signal processing designed to match speech to the residual auditory capacity of a listener with a high frequency hearing loss. A vocoder-based frequency-lowering system similar to one studied by Lippmann was evaluated in the present study. In this system, speech levels in high frequency bands modulated one-third-octave bands of noise at low frequencies, which were then added to unprocessed speech. Results obtained with this system indicated, in agreement with Lippmann, that processing improved the recognition of stop, fricative, and affricate consonants when the listening bandwidth was restricted to 800 Hz. However, results also showed that processing degraded the perception of nasals and semivowels, consonants not included in Lippmann's study. Based on these results, the frequency-lowering system was modified so as to suppress the processing whenever low frequency components dominated the input signal. High and low frequency energies of an input signal were measured continuously in the modified system, and the decision to process or to leave the signal unaltered was based on their relative levels. Results indicated that the modified system maintained the processing advantage for stops, fricatives, and affricates without degrading the perception of nasals and semi-vowels. The results of the present study also indicated that training is an important consideration when evaluating frequency-lowering systems. 相似文献
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