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981.
R. J. Connelly Ph.D. 《Journal of religion and health》1986,25(3):227-236
The Christian has a unique resource for responding to the problem of how competent adults can exercise responsibly the right to control the last stages of their living/dying. Recent natural death legislation offers only a partial solution, because it does not specify what counts as life-sustaining procedures which may be discontinued if the individual fills out a directive to the physician. One of the most troublesome questions continues to be whether the withholding or withdrawal of artificial feeding, or indeed natural feeding, is ever justifiable. An adaptation of principles included in the Christian idea of fasting seems to provide adequate criteria for determining when forgoing nourishment by the terminally ill adult is morally justifiable. 相似文献
982.
Preference for less segmented fixed-time components in concurrent-chain schedules of reinforcement 总被引:1,自引:1,他引:0 下载免费PDF全文
A concurrent-chain procedure was used to examine choice between segmented and less segmented response-independent schedules of reinforcement. A pair of independent, concurrent variable-interval 60-s schedules were presented in the initial link, along with a 1.5-s changeover delay. A chained fixed-interval fixed-time and its corresponding tandem schedule constituted the terminal links. The length of the fixed-interval schedule in the terminal link was varied between 5 s and 30 s while that of the fixed-time schedule was kept at 5 s over conditions. The first components of both terminal-link schedules were accompanied by the same stimulus. Except in the baseline condition, the onset of the second component of the terminal-link chained schedule was accompanied by either a localized (key color) or a nonlocalized (dark houselight) stimulus change. Stimulus conditions were constant during the terminal-link tandem schedule. With three exceptions, pigeons demonstrated a slight preference for the tandem over the chained schedule in the terminal link. Furthermore, this preference varied inversely with the length of the first component. In general, these results are consistent with previous studies that reported an adverse effect on choice by segmenting an interval schedule into two or more components, but they are inconsistent with studies that reported preference for signaled over unsignaled delay of reinforcement. 相似文献
983.
Deprivation and satiation: The interrelations between food and wheel running 总被引:2,自引:1,他引:1 下载免费PDF全文
Two experiments were designed to assess whether depriving rats of food would increase the reinforcement effectiveness of wheel running (Experiment 1) and whether satiation for wheel running would decrease the reinforcement effectiveness of food (Experiment 2). In Experiment 1, a progressive-ratio schedule was used to measure the reinforcement effectiveness of wheel running when rats were deprived or not deprived of food. Completion of a fixed number of lever presses released a brake on a running wheel for 60 s, and the response requirement was systematically increased until the rat stopped pressing or until 8 hr had elapsed. The ratio value reached (and the total number of lever presses) was an inverted-U function of food deprivation (percentage body weight). In Experiment 2, when wheel running preceded test sessions, fewer food-reinforced lever presses were maintained by the progressive-ratio schedule, and responding occurred at a lower rate on a variable-interval schedule. An interpretation of these results is that deprivation or satiation with respect to one event (such as food) alters the reinforcement effectiveness of a different event (such as access to wheel running). 相似文献
984.
Syntactic decoding reaction times of 20 learning disabled children comprising two groups of subjects (mean age of 8 and 13 yr., respectively) were compared to the responses of normal controls matched for age and sex. An analysis of variance procedure showed that the learning disabled children and their normal peers did not differ significantly in responses to the experimental stimuli. This held true regardless of linguistic complexity, suggesting that delays in processing elementary syntactic constructions are not a concomitant of learning disabilities. 相似文献
985.
The purpose of this study was to assess difference in academic performance among myopic, hyperopic, and emmetropic children who were learning disabled. More specifically, myopic children were expected to perform better on mathematical and spatial tasks than would hyperopic ones and that hyperopic and emmetropic children would perform better on verbal measures than would myopic ones. For 439 learning disabled students visual anomalies were determined via a Generated Retinal Reflex Image Screening System. Test data were obtained from school files. Partial support for the hypothesis was obtained. Myopic learning disabled children outperformed hyperopic and emmetropic children on the Key Math test. Myopic children scored better than hyperopic children on the WRAT Reading subtest and on the Durrell Analysis of Reading Difficulty Oral Reading Comprehension, Oral Rate, Flashword, and Spelling subtests, and on the Key Math Measurement and Total Scores. Severity of refractive error significantly affected the Wechsler Intelligence Scale for Children--Revised Full Scale, Performance Scale, Verbal Scale, and Digit Span scores but did not affect any academic test scores. Several other findings were also reported. Those with nonametropic problems scored higher than those without problems on the Key Math Time subtest. Implications supportive of the theories of Benbow and Benbow and Geschwind and Behan were stated. 相似文献
986.
987.
988.
R Goertchen N Grunow T Münchow E Goertchen 《Psychiatrie, Neurologie, und medizinische Psychologie》1986,38(3):128-132
Based on 2130 autopsies with a hypertension it is reported on the hypertensive CNS-lesions. The frequency of encephalomalacia was 12%. By 9.7% was founded brain haemorrhages. The relapse rate of haemorrhages was about 5%. The encephalomalacia existed by way of secondary finding in 24.7%, and the haemorrhage in 2.2%. The investigations showed an important arteriosclerosis by 39.8% in haemorrhages and by 51.6% in brain infarct. It was remarkable by the hypertensive brain haemorrhages a dominant right hemisphere. 相似文献
989.
Of 1028 patients with 1138 peripheral nerve lesions, 142 suffered from an electrophysiologically proven SUS. At follow-up, 93 patients could be restudied. Spontaneous regressions were observed in patients below the age of 40 years and in case of a history under 6 months. So-called late pareses receded in no case without operative displacement of the ulnar nerve. However, if the etiology is unknown, the present results of investigation require reserve towards operative therapy. 相似文献
990.
G Sack H J Leubuscher B P?gelt N Roth 《Psychiatrie, Neurologie, und medizinische Psychologie》1986,38(5):246-254
The influence in 8 of our patients with ophthalmic migraine of photic driving with sine-like flashing lights on EEG background activity was checked and the visually evoked potentials following the application of diffused simple light stimuli were analyzed using the recovery cycle technique. The results indicate a slightly increased tonic activity of the structures of the mesencephalic formatio reticularis, such as may be produced by slight functional disturbances. Some vegetative secondary symptoms of migraine attacks and some of the changes in EEG observed in patients with ophthalmic migraine are explicable by such an abnormality. 相似文献