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Hidekatsu Yokoyama Shin-ichi Niwa Kenji Itoh Reiko Mazuka 《Biological cybernetics》1996,75(2):137-140
On the basis of a temporal model of animal behavior we conducted temporal analysis of eye movements in schizophrenic subjects
(n=10) and normal controls (n=10). We found a fractal property in schizophrenic subjects, the fixation time of eye movement during reading ambiguous and
difficult sentences showing a clear inverse power law distribution. An exponential distribution of a nonfractal nature was
found in normal controls.
Received: 21 July 1995/Accepted in revised form: 30 April 1996 相似文献
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This study examined the effects of nitrogen anaesthesia and cycloheximide injection on memory of the classically-conditioned fly, Phormia. 1 M NaCl solution was given to each fly as a conditioning stimulus and 0.5 M sucrose solution was the unconditioned stimulus that induced the proboscis extension response. The training period was as short as 2 min and testing was usually carried out 2 hr later. At varying times (0–60 min) between training and testing, flies were anaesthetized with nitrogen gas for 25 sec. When flies were anaesthetized immediately after training the effect of nitrogen gas was the greatest and few flies showed any conditioned response, but the sensitivity of memory to nitrogen gas declined as the interval between training and nitrogen treatment became longer, and such treatment had no effect on memory when the interval was longer than 30 min. The effect on memory of cycloheximide, an inhibitor of peptide bond synthesis, was also investigated. The injection of cycloheximide (0.37 μg) immediately after training diminished the memory, but when given 1 hr after training it had no effect on memory. These results show that the memory in Phormia has two phases, stable and an unstable phase, like long-term and short-term memory in vertebrates. 相似文献
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The kinetics of haemolysis of rabbit erythrocytes byCroton tiglium lectin was studied as a function of concentration of the lectin and erythrocytes. The length of the prelytic period decreased with increasing lectin concentrations, indicating that the secondary events at the membrane which follow the binding of the lectin to cell surface carbohydrate receptors are accelerated at higher surface concentrations of the lectin. The rate or extent of haemolysis was not affected by the inclusion of ions like K+, Ca2+ and Mg2+ in the medium or by the substitution of ionic medium by a non-ionic medium. The inhibition of haemagglutination and haemolysis of rabbit red cells byCroton tiglium lectin by antilectin rabbit serum was observed. A possible mechanism of haemolysis by the lectin is discussed. 相似文献
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N-Acetyl-D-galactosamine in β-linkage being ubiquitous in cell surface glycoproteins, their interaction with lectins specific for this sugar moiety may be a significant event in cell adhesion phenomena. This article discusses the common β-N-acetyl galactosamine-specific lectins, with particular stress on the lectin from winged beans (Psophocarpus tetragonolobus). 相似文献