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201.
We previously reported that a total methanolic extract of the underground part of Angelica gigas Nakai (Umbelliferae) (here-in-after abbreviated AG) significantly inhibited acetylcholinesterase (AChE) activity. We characterized 12 coumarin derivatives including both decursin and decursinol from extracts of AG. In this study, we evaluated the anti-amnestic activity of decursin, a major coumarin constituent isolated from AG, in vivo using ICR mice with amnesia induced by scopolamine (1 mg/kg body weight, s.c.). Decursin, when administered to mice at 1 and 5 mg/kg body weight i.p., significantly ameliorated scopolamine-induced amnesia as measured in both the passive avoidance test and the Morris water maze test. Moreover, decursin significantly inhibited AChE activity by 34% in the hippocampus of treated mice. These results indicate that decursin may exert anti-amnestic activity in vivo through inhibition of AChE activity in the hippocampus.  相似文献   
202.
A novel, neuropsychologically informed paradigm (extended retrieval of events in response to a cue word) was used to investigate the neural basis of autobiographical and semantic memory. Contrasting retrieval of autobiographical memories with retrieval of semantic facts (ABM-SEM) in 24 subjects across three PET studies revealed bilateral involvement of the middle temporal gyrus (BA 21) and medial frontal cortex (BA 9/10). The opposite contrast, SEM-ABM, resulted in increased regional cerebral blood flow in left posterior temporal regions (BA 37) and left prefrontal cortex (BA 45/46). Laterality maps suggest that the bilateral pattern seen in our studies, but not often in other neuroimaging investigations, reflects the use of a task stressing retrieval of specific personal events. Further comparisons revealed that the activation in the right anterior temporal lobe during autobiographical recall was virtually identical to that seen during retrieval of information about famous people or events in contrast with retrieval of general semantic facts. These findings suggest that the retrieval of an autobiographical event requires participation from conceptual knowledge, and that this type of knowledge is bilaterally distributed in the temporal lobes.  相似文献   
203.
We trained pigeons to peck two different buttons in response to 16-iconsame arrays versus 16-icondifferent arrays. In thesame arrays, the icons were all the same as one another, whereas in thedifferent arrays, the icons were all different from one another. In Experiment 1, we upset the spatial regularities of the displays by disarranging the icons—randomly displacing each icon to reduce the degree of perceptual order. The pigeons’ discriminative performance was unaffected by disarranging. In Experiment 2, spatial regularities were disturbed by varying the rotation of the icons within a display. Again, no disruption in discriminative performance was observed. These and other findings suggest that pigeons treat the 16 icons as either the same or different despite changes in the spatial organization or orientation of the icons, thus implicating a conceptual rather than a perceptual process in same—different discrimination.  相似文献   
204.
The role that recent experience has in the processing of Korean Hanja characters was investigated in two masked priming experiments. Two groups of Korean native speakers that differed in their recent exposure to Hanja were asked to name single Hanja characters (targets) that were immediately preceded by masked presentations of the same characters (repetition priming), Hanja characters that were homophones of the target (homophone priming), or unrelated characters (baseline). The results showed that the group that had been less recently exposed made more errors and were slower than the group that had been the more recently exposed. Furthermore, there was no character homophone priming for the less recently exposed group, although they did show a robust repetition priming effect. On the other hand, the more recently exposed group showed both strong character repetition and homophone priming effects. We suggest that regular exposure to characters supports their rapid and automatic processing. It is argued that the different patterns of priming for the two groups were due to how rapidly the orthographic and phonological information of the prime could be resolved.  相似文献   
205.
Joohan Kim 《Human Studies》2001,24(1-2):87-111
This paper explores the ontology of digital information or the nature of digital-being. Even though a digital-being is not a physical thing, it has many essential features of physical things such as substantiality, extensions, and thing-totality (via Heidegger). Despite their lack of material bases, digital-beings can provide us with perceivedness or universal passive pregivenness (via Husserl). Still, a digital-being is not exactly a thing, because it does not belong to objective time and space. Due to its perfect duplicability, a digital being can exist at multiple locations simultaneously – that is, it defies normal spatiotemporal constraints. With digital beings on the Internet, we can establish intercorporeal relationships. The World Wide Web opens up new possibilities of Dasein's being-able-to-be-with-one-another and new modes of Being-with-others (Mitsein). The new modes of communication based on digital-beings compel us to re-read Heidegger's basic concepts such as Dasein as Being-in-the-world, since Dasein becomes the Digi-sein as Being-in-the-World-Wide-Web. By exploring the ontological characteristics of digital-being, this paper suggests that we conceive digital-beings as res digitalis – a third entity which is located somewhere between res cogitans and res extensa.  相似文献   
206.
Kim O  Kim K 《Adolescence》2001,36(142):315-322
The purpose of this study was to examine whether body mass index (BMI) and perception of a body weight problem predict level of self-esteem and depression in Korean female adolescents. The sample consisted of 303 females, ranging in age from 15 to 19 years, who were attending four high schools located in Seoul, Korea. BMI and desired BMI were calculated based on self-reported weight and height. Self-perception of having a weight problem was evaluated by one question: "Do you see yourself as having a weight problem?" Self-esteem was measured using the Rosenberg Self-Esteem Scale, and depression was measured using the Center for Epidemiologic Studies Depression Scale. Based on BMI, 18.2% of the females were underweight, 79.2% were of normal weight, and 2.6% were overweight. Based on desired BMI, 78.5% of the females desired to be underweight. Results showed that perception of a weight problem, but not BMI, contributed significantly to the prediction of level of self-esteem and depression. In addition, there was a significant positive correlation between BMI and perception of a weight problem.  相似文献   
207.
In two experiments using spatial probes, we measured the temporal and spatial interactions between top-down control of attention and bottom-up interference from a salient distractor in visual search. The subjects searched for a square among circles, ignoring color. Probe response times showed that a color singleton distractor could draw attention to its location in the early stage of visual processing (before a 100-msec stimulus onset asynchrony [SOA]), but only when the color singleton distractor was located far from the target. Apparently the bottom-up activation of the singleton distractor's location is affected early on by local interactions with nearby stimulus locations. Moreover, probe results showed that a singleton distractor did not receive attention after extended practice. These results suggest that top-down control of attention is possible at an early stage of visual processing. In the long-SOA condition (150-msec SOA), spatial attention selected the target location over distractor locations, and this tendency occurred with or without extended practice.  相似文献   
208.
The relations between temperament and empathy in 2-year-olds.   总被引:2,自引:0,他引:2  
The role of infant and toddler temperament in the prediction of empathy in 2-year-old children was examined. Assessments of temperament included reactivity and affect observed at 4 months of age, as well as inhibition at Age 2. Empathy was measured in 2-year-old children's responses to simulations of distress performed by their mothers and by an unfamiliar person. Children showed relatively more concern for the mother's distress, but they were also responsive to unfamiliar victims. Infants who were unreactive and showed little affect also showed less empathy toward the unfamiliar adult almost 2 years later. Inhibition toward an unfamiliar adult (but not toward the mother) at 2 years of age was negatively related to empathy. Inhibited temperament may thus have a major impact on young children's empathy in unfamiliar contexts. Findings also highlight the need to consider early underarousal as another dimension of temperament that may dampen expressions of empathic concern.  相似文献   
209.
Kim L. Beckmann 《Zygon》1999,34(3):537-541
This Christian sermon uses a DNA lab experience as a basis for theological reflection on ourselves and our offering. Who are we to God? What determines the self that we offer? Can the alphabet of DNA shed light for us on the Word of God in our lives? This first attempt to introduce the language and laboratory environment of genetic testing (represented by DNA fingerprinting) within a parish preaching context juxtaposes liturgical, scientific, and biblical language and settings for fresh insights.  相似文献   
210.
In 3 experiments, the authors examined movement space-time variability as a function of the force-time properties of the initial impulse in a movement timing task. In the range of motion and movement time task conditions, peak force, initial rate of force, and force duration were manipulated either independently or in combination across a range of parameter values. The findings showed that (a) impulse variability is predicted well by the elaboration of the isometric force variability scaling functions of L. G. Carlton, K. H. Kim, Y. T. Liu, and K. M. Newell (1993) to movement, and (b) the movement spatial and temporal outcome variability are complementary and well predicted by an equation treating the variance of force and time in Newton's 2nd law as independent random variables. Collectively, the findings suggest that movement outcome variability is the product of a coherent space-time function that is driven by the nonlinear scaling of the force-time properties of the initial impulse.  相似文献   
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