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901.
This paper describes an amplifier for an electroencephalograph with gain of 1×104 to 1×106 and made entirely of commercially available IC components. The two-stage amplifier has a preamplifier stage with fixed gain of 1000, and a second stage with variable gain from 1 to 100. The final stage, an anti-aliasing filter, adds a gain of 10 to the signal. The circuit has high common mode rejection, low input bias current, very low noise characteristics, low offset voltages, and offset nulling capability built into the circuit.  相似文献   
902.
We outline a BASIC program and subsidiary machine language timing routines that enable the Apple II series of computers to be employed as control devices for the tachistoscopic presentation of 35-mm slides and the collection of response latencies. The program is functional for experiments that require pictorial stimuli to be presented in up to three separate fields, with precise display times, precise interstimulus and intertriai intervals, and the collection of manual or vocal reaction times with millisecond accuracy. The major advantages of this system are that initial setup costs are substantially lower than those for other similar systems (e.g., Loftus, Gillispie. Tigre, & Nelson, 1984) and that user customization of the program may be accomplished by anyone possessing rudimentary knowledge of the BASIC programming language.  相似文献   
903.
In contrast to theoretical discussions about potential professional liability of clinical ethicists, this report gives the results of empirical data gathered in a national survey of clinical medical ethicists. The report assesses the types of activities of clinical ethicists, the extent and types of their professional liability coverage, and the influence that concerns about legal liability has on how they function as clinical ethicists. In addition demographic data on age, sex, educational background, etc. are reported. The results show that while nearly one third (28.9%) of the ethicists regularly make recommendations about patient care, only 10.8% of them regularly make entries in the medical record; only approximately half (53.0%) of them are covered by professional liability (malpractice) insurance; and the vast majority (84.3%) of them say that concerns about legal liability do not influence the way they function as clinical ethicists.  相似文献   
904.
A unique relationship exists between physicians and philosophers — one that expands on the constructive potential of the liaison between physicians and, for example, theologians, on the one hand, or, social workers on the other. This liaison should focus in the scientific aspects of medicine, not just the ethical aspects. Philosophers can provide physicians with a perspective on both the philosophy and the history of medicine through the ages — a sense of how medicine has adapted to the social cultural and ethical needs of each period. This perspective, while emphasizing medicine asscience, should not be limited to matters of methodology, or to criteria for distinguishing science from other intellectual pursuits, but should be concerned also with the history, sociology and politics of science. Both physicians and philosophers stand to gain from a strengthening of their active liaison now as never before; but most of all, the public will be the beneficiary.  相似文献   
905.
This paper examines the reactions of physicians and other health-professionals when they become involved in decisions about the death of their patients. The way people understand the condition of death has a profound influence on attitudes towards death and dying issues. Four traditional views of death are explored. The problem that physicians have in helping patients die (be it by hastening death through pain control, assisting patients in suicide or by more active means) is analyzed. Physicians, in dealing with such patients, must be mindful of their own, and their patients beliefs as well as mindful of the community in which such dying takes place. They must try to reconcile these often divergent views but can neither paternalistically deny patients their rational will, hide themselves behind an appeal to the law or go against their own deeply held moral views. When such views cannot be reconciled, compassionate transfer to a more compatible physician may be necessary.  相似文献   
906.
Males were randomly assigned to view either (1) a film clip featuring hockey fights or (2) a film of nonaggressive hockey action or (3) a no-film control condition after having first been angered or treated politely by an experimental confederate. The dependent variable was represented by a measure of aggressive mood and a behavioral measure of retaliatory aggression. Analyses revealed that both angered and nonangered subjects exhibited an increase in aggressive mood following exposure to the fight film. However, the analysis involving retaliatory aggression against the confederate yielded an anger x film interaction. While angered subjects were more aggressive than nonangered, only angered subjects retaliated against the confederate after viewing the fight film. The results were discussed in terms of Berkowitz’s (1974) aggressive cue theory. A version of this paper was presented at the meeting of the North American Society for the Sociology of Sport, Edmonton, Canada, November 1987.  相似文献   
907.
Fear of Success (FOS) was originally conceived as a unidimensional motive. However, there is both theoretical and empirical support for the hypothesis that FOS is multidimensional. We factor analyzed the responses of 236 undergraduates to twenty-oneConcern Over the Negative Consequences of Success items and found four factors. Our four factors show considerable overlap with dimensions based on theoretical accounts of FOS etiology as well as with the factor structures obtained from two other factor analytic studies. Thus, there is converging evidence that FOS is multidimensional. The relationship between multidimensional FOS and a multidimensional approach to achievement motivation is discussed.  相似文献   
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