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41.
The results of an evaluation of the perfusion scintigraphy findings of 350 hospitalised neurological patients and 55 more strictly selected neurosurgical patients with cerebrovascular complaints, revealed an accuraty of 83%, a sensitivity of 89%, and a specificity of 83%. The selection of the patients had no influence on the results as a whole. Compared with contrast-medium angiography, incorrect diagnosis must be expected in 17% of the cases. This includes erroneous negative findings in 10% of the cases. Grounds for misinterpretations are suggested, and the biological and methodological limitations of the method are set forth.  相似文献   
42.
We compare over a two-octave range the tonal, interval, and scale relationships of an ancient Chinese bell ensemble of the Zhou Dynasty and a modern bamboo flute. By using subjective pitches, a tonal system with simple harmonic partials (the flute) could be compared with a tonal system with complex inharmonic partials (the bell). We argue that the underlying musical scales of the bell ensemble and the flute are closely related and lie between an unequal-interval pure-system scale and the just-intonation scale. There is some evidence that a least interval of 60 or 66 cents figures in the flute scale, that both flute and bell scales include a 90-cent interval and a true (1,200-cent) octave, and that neither scale includes a 100-cent interval. Since there is a true octave, the scales cannot be cycles of fifths, and since there is no equal-temperament half-tone (100 cents), the scales cannot be equal in temperament. We conclude that the flute and Zhou bell scales are very similar if not the same. Apparently, strong cultural traditions and human perceptual constancies united to sustain a common flexible musical scale during 2,400 years.  相似文献   
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44.
The psychotherapeutic life-work of psychiatrist Arthur Kronfeld has almost fallen into oblivion. Against the background of the 100th anniversary of his birth the author traces Kronfeld's psychotherapeutic career, pointing out his activity at the Berliner "Institute of Sexual Research" under Magnus Hirschfeld, and his psychotherapeutic concept--the psychagogic guidance of the patient--and its connection with the individual psychology of Alfred Adler. Kronfeld translated his theoretical positions into activities directed towards socialization and the teachability of psychotherapy which are still worthy of note by those engaged in the field.  相似文献   
45.
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   
46.
Twenty six clinically healthy smokers were studied with transient pattern visual-evoked potentials. In comparison with a sample of "normal" subjects we found a difference of some parameters (P less than 0.05): the P2-latency and the interocular difference of latency on average were 6-7 ms respectively 2 ms larger. Thirteen subjects have had a prolonged P2-latency (P less than 0.05) and/or a difference in interocular latencies larger than 5 ms. These findings may suggest on subclinical disturbances of visual system and indicators of an special sensitivity of that person. The findings are possibly related to tobacco-alcohol amblyopia.  相似文献   
47.
Aged rats with extensive prior training on the radial maze retain the capacity for accurate spatial working memory (WM) for at least 3 months without practice. To investigate the temporal limits of this influence of prior experience we compared the reacquisition of spatial WM by a group of experienced 21.5-month-old rats to the original acquisition by naive 3-month-old rats. The aged rats had received 225 radial maze tests between 3 and 11 months of age. Despite 10 months without practice the old rats rapidly reacquired critical performance. Their reacquisition was markedly superior to original learning by the young rats, even when delays as long as 5 h were imposed between the rats' fourth and fifth choices during the daily tests in the eight-arm maze. Additional tests showed that neither young nor old rats employed a response strategy to maintain accurate spatial WM performance. Experience clearly confers long-lived protection against the otherwise deleterious effects of aging on spatial WM, but the mechanism by which this influence arises is unknown.  相似文献   
48.
The ability to think of a previously studied item has often been shown to be impaired when, in one way or another, the extraitem context is changed from study to test. In a series of five experiments, such impairment is induced in a somewhat different way. A fragment (e.g. r-i--rop) of a just-studied word (raindrop) is shown to be less readily completed if it is presented bit by bit (r------p, r----r-p, r-i--r-p, r-i--rop) rather than all at once (Experiments 1, 3, 4, and 5). No such effect is found if the word has not been studied beforehand (Experiments 2, 3, 4, and 5). This pattern of results occurs even when fragments of studied and nonstudied words occur in the same test and under conditions in which subjects cannot tell whether a given fragment is of a studied or nonstudied word (Experiments 4 and 5). In addition, for words that have been studied beforehand, the impairment is shown to increase systematically with the number of steps involved in the presentation of the word fragment (Experiment 3) and also to persist when the time allowed for completion of the final version of the fragment is increased from 4 s to a full minute (Experiment 5).  相似文献   
49.
吴永祥  王秉光 《心理学报》1984,17(3):98-103
本文是以大白鼠在三等分迷宫仪中学习防御性条件反应的方法,观察800拉特γ-线对大白鼠学习能力的影响。实验结果表明,大白鼠的学习能力是下降的,其表现为每天学习的正确率低,达到学会标准所需学习次数增加;反应运动时延长;主动躲避反应的出现率降低。 根据受照动物的特点,我们认为:作为判断学习和记忆能力的指标,反应运动时比正确率更好一点。  相似文献   
50.
本工作研究两例先天性无痛症患者的心理特点,主要是其情绪特点,以探讨疼痛和情绪的关系,并借以检验疼痛学说的意义。例一,女,10岁,智力略低于正常,艾森克少年儿童人格问卷表评定人格正常。与身体损伤有关的恐惧感明显缺乏,但与社会和教育影响有联系的恐惧感却甚于正常儿童。情绪急躁,易发作暴发性脾气而不能控制。在突然刺激(强光、强铃声)下的反应和正常儿童相近。例二,男,13岁,智力明显落后,人格评定正常,各种恐惧感均明显缺乏。情绪经常呈明显欣快状态。突然刺激下有口语惊吓和动作反应但无相应的面部表情和植物性神经系统的变化。两例均有无目的的多动作表现。看来疼痛和情绪有某种关系,但本结果并不能证实疼痛的情绪学说。  相似文献   
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