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991.
The pattern of gangliosides in membranes of erythrocytes was examined in healthy donors, in acute schizophrenics without neuroleptic treatment and in alcohol-dependent patients. 7 different gangliosides could be detected after extraction, purification by column chromatography and fractionation by TLC. Healthy donors were characterized by the following pattern of gangliosides: GX = 5.8%, GT1b = 6.7%, FucGD1b = 5.2%, und GD1a = 12.6%, GD3 = 9.2%, SPG = 43.5% and GM3 = 17.0%. In schizophrenic patients the GM3- and GD3-fraction were increased. No difference was found between the control group and the alcoholics.  相似文献   
992.
In face of catamnestic examinations at a group of 61 older children and juveniles with infantile cerebral palsy we can see, that an optimal attendance by medical specialists, physiotherapists and social workers is not reached yet in each case. 39 patients (64 p.c.) are provided by a specialist regularly, 35 patients (57.4 p.c.) regularly get a physiotherapeutic treatment and 33 patients (54.1 p.c.) are often only sporadically attended by social workers. Serious disabled children, who are nursed only in their families, bring particular problems. In the authors opinion a decisive improvement of attendance is possible. For that purpose a more intensive work of "Dispensaries for disabled children and juveniles" in connexion with a consistent utilization of the socialist legislation is necessary.  相似文献   
993.
994.
U Goswami  A L Brown 《Cognition》1990,35(1):69-95
Children's performance in the classical a:b::c:d analogy task is traditionally very poor prior to the Piagetian stage of formal operations. The interpretation has been that the ability to reason about higher-order relations (the relations between the a:b and c:d parts of the analogy) is late-developing. However, an alternative possibility is that the relations used to date in the analogies are too difficult for younger children. Two experiments presented children aged 3, 4 and 6 years with a:b::c:d analogies which were based on relations of physical causality such as melting and cutting, for example chocolate bar:melted chocolate::snowman:melted snowman. Understanding of these particular causal relations is known to develop between the ages of 3 and 4 years. It was found that even 3-year-olds could solve the classical analogies if they understood the causal relations on which they were based.  相似文献   
995.
Phonological priming and orthographic analogies in reading   总被引:2,自引:0,他引:2  
Recent work has demonstrated that children can use orthographic analogies between the spelling patterns in words to help in decoding new words (e.g., using beak to read peak; Goswami, 1986, 1988). However, one objection has been that these analogy effects may be due to phonological priming. Two experiments examined the phonological priming alternative. In Experiment 1, a single word reading task compared the use of analogies to read words that shared both orthography and phonology (e.g., most-post), that shared orthography only (e.g., most-cost), or that shared phonology only (e.g. most-toast--the phonological priming condition). Limited effects of phonological priming were found. Experiment 2 then presented the same words embedded in prose passages--"real reading." While the orthographic analogy effect remained robust, the small phonological priming effect disappeared. It is argued that phonological priming is an insufficient explanation of the analogy effect at the single word level, and plays no role in the use of analogies in story reading.  相似文献   
996.
中、英文阅读理解之比较研究   总被引:4,自引:0,他引:4  
本文在句法、语义和事实方面比较了中、英文的阅读过程,并发现中文读者在阅读加工中更多地采用分散的策略,而英文读者则更多地采用集中的策略。在中文中,语义违反所造成的朗读混乱大于句法违反所造成的混乱;而在英文中则句法违反所造成的混乱大于语义违反所造成的混乱。但是,由句法、语义和事实的违反所形成的曲线在中、英文中是相似的,这说明中、英文的阅读加工有其共同之处。  相似文献   
997.
In this paper are described two systems for spatial (two-dimensional coordinates) and temporal analysis of video images. In the optical version, the Apple IIe generates a pointer on an Apple monitor; the pointer is then superimposed on the video image of a second video monitor, by reflecting the pointer with a half-silvered mirror. In the electronic version, a special card was designed for the Apple IIe to generate a pointer directly on the other video monitor. Both systems use the same software. The procedures of spatial and temporal data acquisition and storage are described as well as the reading, writing, printing, removing, listing, chaining, and dating operations of the digital and graphics files.  相似文献   
998.
Summary Global superiority refers to the phenomenon that stimuli can be discriminated, classified, and matched faster using a global feature than a local feature. Global superiority has been shown by several authors with forms (global feature) composed of smaller forms (local features) as stimuli. In contrast, the local features used in the present study had about the same spatial extent as the global feature and each local feature was structurally relevant to the global feature. Nevertheless, global superiority was consistently observed in several classification and matching tasks. This result, together with the results of other researchers using different stimulus materials shows that global superiority is a pervasive phenomenon. Under brief exposure durations within the threshold range, local features could, however, be better discriminated than global features. This finding invalidates the perceptual explanation of global superiority that global features are faster extracted and, in this way, become available earlier than local features. Considering the magnitude of the observed differences between classification times and threshold durations of global and local features, it is argued that under normal viewing conditions global features can be better selected and utilized for the given task than local features, and that this advantage by far outweighs the faster feature extraction of local features.This research was supported by Grant Wa 419/3 from the Deutsche Forschungsgemeinschaft  相似文献   
999.
Rested adult golden hamsters produced a mean of 13 ejaculations and then showed a modified copulatory pattern consisting of long intromissions (10-30 s of intravaginal thrusting) during which no sperm transfer occurs. When a second (fresh) female was introduced, 58% of the males produced at least one more ejaculation, and 17% of the males produced one further ejaculation when placed with a third female. In similar three-female tests conducted 24 hr later, all males ejaculated (M = 4 ejaculations); this level of ejaculatory output was maintained over a subsequent 10-day period of daily testing. Four ejaculations ensured a nearly 100% pregnancy rate and maximum litter size in the first females. Second and third females, however, received fewer ejaculations and subsequently showed reduced fertility and produced smaller litters. Most males showed high levels of long intromissions on all days and with all females. The physiological significance of these long intromissions may be to trigger the progestational response. Examination of the rate of recovery from sexual exhaustion indicated that 2 or 8 hr of rest resulted in fewer than 50% of the males being capable of one further ejaculation. However, most of these single ejaculations were accompanied by long intromissions and resulted in successful pregnancies. Four to eight days were required for full recovery of ejaculatory capacity. This study showed that the male golden hamster has a higher ejaculatory output and more rapid recovery from sexual exhaustion than other small rodents that have been studied. Thus, the limits of male capacity appear to vary widely among species.  相似文献   
1000.
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