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991.
By 48 patients with Wilson's disease the brainstem acoustic evoked potentials were stated. There were 35 pathological findings (73%), 13 were normal (27%). The waves, determined by the middle and upper brainstem (Pons and Mesencephalon) showed most of all pathological changes. Those patients with forms of Wilson's disease called Pseudoskelerose and Pseudoparkinson showed the most pathological findings. But one could watch these findings by about 30% of patients in preclinical stage. This method can possibly be used for early detection of disorders of brainstem functions and in the same way it can be used for control of treatment by patients in preclinical stage.  相似文献   
992.
The authors compared with regard clinical and the radionuclide cisternography examination 27 patients with Hakim-Syndrome and 11 with Alzheimer-Disease. In all cases, dementia was a stable symptom. Patients with Hakim-Syndrome have an early gait disturbance, ataxia and epileptic seizures. Only in case of patients with Alzheimer-Disease we found aphasia, apraxia and psychotic disorders. 24 hours after the injection radionuclide cisternography showed ventricular retention and absence of parasagital accumulation only in patients with Hakim-Syndrome. Lighter changes (mixed cisternographic pattern) were found in patients with Alzheimer-Disease as well.  相似文献   
993.
994.
Is there a cell-biological alphabet for simple forms of learning?   总被引:5,自引:0,他引:5  
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995.
The partial derivatives of the squared error loss function for the metric unfolding problem have a unique geometry which can be exploited to produce unfolding methods with very desirable properties. This paper details a simple unidimensional unfolding method which uses the geometry of the partial derivatives to find conditional global minima; i.e., one set of points is held fixed and the global minimum is found for the other set. The two sets are then interchanged. The procedure is very robust. It converges to a minimum very quickly from a random or non-random starting configuration and is particularly useful for the analysis of large data sets with missing entries.This paper benefits from many conversations with and suggestions from Howard Rosenthal.  相似文献   
996.
Programs,language understanding,and searle   总被引:1,自引:0,他引:1  
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997.
998.
In their area of expertise experts know more potentially interfering facts than nonexperts do, yet their memory IS superior to that of nonexperts. This has been termed the “paradox of interference.” We proposed that the ability of experts to go beyond the information given allows them to infer the presence of items that might not otherwise be remembered. However, such inferences can also be detrimental to accurate recognition memory in that such inferences might become confused with actual targets. We examined the benefits and costs of expertise in two recognition memory experiments In which experts and nonexperts participated. Experts in Ex-penment 1 were knowledgeable about baseball; those in Experiment 2 were knowledgeable about Ohio geography. Distractors in both studies bore a synonymous, an inferential, or no special relation to the targets. In the last instance, experts had recognition memory superior to that of the nonexperts. When the distractors were related to the targets, however, the non-experts were superior. We proposed that experts' inferential behavior is a contributor to their generally superior memory, but that task demands can convert this asset into a liability.  相似文献   
999.
Humeanism – the idea that there are no necessary connections between distinct existences – and Nomic Essentialism – the idea that properties essentially play the nomic roles that they do – are two of the most important and influential positions in the metaphysics of science. Traditionally, it has been thought that these positions were incompatible competitors. We disagree. We argue that there is an attractive version of Humeanism that captures the idea that, for example, mass essentially plays the role that it actually does in the laws of nature. In this paper we consider the arguments that have lead many to conclude that Humeanism cannot be combined with Nomic Essentialism; we identify the weaknesses in these arguments; and we argue in detail that a version of Humeanism based on a variant of the Best System account of laws captures the key intuitions behind nomic essentialism.  相似文献   
1000.
With increasing awareness about racism, portrayals of communities of colour are shifting away from negative representations. Emphasizing their strengths could counter negative stereotypes about who they are and low expectations for who they can be, but could also backfire. In two experiments centring adolescents (n = 198) and adults of colour (n = 321), the effect of reflecting on a typical strength was moderated by perceived misalignments between racial/ethnic and ideal future selves (i.e., ethnic–ideal self-discrepancy). For participants perceiving them as aligned, reflecting on a typical in-group strength reduced actual–ideal self-discrepancy. However, for participants perceiving them as misaligned, reflecting on a typical in-group strength increased actual–ideal self-discrepancy. Reflecting on a typical strength also indirectly influenced engagement, through actual–ideal self-discrepancy. Reflecting on an atypical in-group strength did not yield significant effects. Thus, emphasizing typical aspects of stigmatized communities, even when positive, sometimes impede identity and motivation.  相似文献   
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