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901.
It has been demonstrated that death certificates do not accurately record the actual cause of death in up to one-fourth of cases, as determined from subsequent autopsy findings. The purpose of this study was to explore the use of natural language autopsy data bases as an automated quality assurance mechanism. We translated the account of the major process leading to death, or the primary diagnosis, from all 45,564 narrative autopsy reports obtained at The Johns Hopkins Hospital between May 28, 1889, and June 30, 1987, into the hierarchical system of Medical Subject Heading (MeSH) titles. We obtained a total of 125,772 MeSH title translations, 1,563 of them distinct (average 2.8 per case), ranging in frequency from 6,029 occurrences of LUNG to 1 occurrence apiece of 357 MeSH titles. The natural-language-to-MeSH translations showed expected trends over the past century: fewer infectious diseases; more cardiovascular and neoplastic disease among adults; and more respiratory diseases and congenital malformations in the pediatric age group. The greater availability of autopsy documents in electronic form should increase the value of this resource for quality assurance.  相似文献   
902.
The Dating Anxiety Survey (DAS) was constructed to assess dating anxiety in males and females. Factor analysis of the survey revealed three factors: passive contact, active intentions for dating, and dating interactions. The reliabilities of the three subscales, as determined by coefficient alpha, were .87, .91, and .93 for males and .90, .90, and .92 for females, respectively. Correlations with dating history and a measure of social anxiety were generally of a low but significant magnitude, providing some support for concurrent validity. The results of the factor analysis lend support to the construct validity of the DAS. These findings suggest that the DAS is a potentially useful instrument in the self-report of dating anxiety.Portions of this paper were presented at the meeting of the Southeastern Psychological Association, Atlanta, GA, March 1983.  相似文献   
903.
There are a large number of exogenous biological and chemical substances with known neoplastic or carcinogenic potential. However, it has also been postulated that external stimuli can influence the body's internal milieu, and thereby induce compensatory excessive growth of cells in the form of hyperplasia or neoplasia. In a recent study, we observed a strong association between chronic hypoxic states and the occurrence of peripheral neuroblastic tumors, a relatively uncommon group of neural neoplasms. In this report we review those findings and formulate an hypothesis to explain why conditions which lead to chronic erythrocytosis may also cause compensatory neoplasia of neural tissues.  相似文献   
904.
905.
Conditioning of the rabbit nictitating membrane response was found to be inversely related to the number (0, 50, 200, 350) and intensity, (0, 1, 3, 5 mA) of preacquisition UCS exposures and directly related to the interval between preexposure and acquisition (0 or 24 hr). The results were discussed in terms of sensory adaptation, habituation, blocking, and emotional reactivity.  相似文献   
906.
907.
Infants show an adaptive avoidance response to approaching objects. The response is affected by the closeness and speed of approach. It is mediated by visual variables. Air-pressure changes do not elicit the response. This kind of response implies discrimination and response to distal variables rather than merely to their proximal mediators.  相似文献   
908.
909.
Pattern recognition models for the perception of complex tones assume that the pitch of a complex tone is derived from more primary sensations, such as the pitches of the individual partials. Thus a complex tone will only have a well-defined pitch when at least one partial in the complex is separately perceptible. Models based on time-interval measurements, on the other hand, require an interaction of the original components, so that the periodicity of the input waveform is preserved. In Experiment I the relative intensity of a “target” tone, necessary for its identification in the presence of either one or two “masking” tones, was determined, over a range of frequencies. This intensity changes abruptly at around 5 kHz, a result consistent with the idea that the pitches of pure tones are determined by temporal mechanisms for frequencies up to 5 kHz, and by place mechanisms for frequencies above this. In Experiments II and III the audibility of the partials in a multi-tone complex was measured as a function of their frequency separation and compared with the range of conditions over which a complex stimulus produced a clear pitch sensation, using the same set of subjects in each experiment. It was found that under some conditions the complex had a well-defined pitch when none of the individual partials was separately audible. This is contrary to the predictions from the pattern recognition models. The effects of masking noise in the frequency region below the complex, and the results of individual subjects, also did not conform with the predictions from these models. Such models are not ruled out, however, for low harmonic numbers, or for stimuli containing only a small number of partials.  相似文献   
910.
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