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991.
The methods of nuclear medicine and electro-encephalography allow, in combination, in almost every case the answer to the question of the cerebral tumour relapse. Our evaluation confirms the discovery of the greater sensitivity of the isotopic methods with relapses of glioblastomas, while relapses of meningiomas, astrocytomas, oligodendrogliomas and spongioblastomas can be recognized more frequently only by electro-encephalographic methods. The value of angiography is limited in cases of cerebral tumour relapses without pathological vascularisation, since the swelling can spread in the resection cavity without retroaction on the surrounding areas. For this reason vascular displacement (an only be observed very late on. Clinical judgement is furthermore complicated by the fact that after the removal of the primary tumour, often no reposition of the arteries ensues. After our exainations, a negative angiographic condition can be rule out a diagnosis of a relapse which has been established by electro-encephaolographic and isotopic methods.  相似文献   
992.
993.
Seventy-one entrepreneurs and 62 non-entrepreneurs were given tests of Locus of Control and Risk-taking Propensity, as well as nAch. Significant differences were found and led to a clarification of the concept of entrepreneurship.  相似文献   
994.
Rested adult golden hamsters produced a mean of 13 ejaculations and then showed a modified copulatory pattern consisting of long intromissions (10-30 s of intravaginal thrusting) during which no sperm transfer occurs. When a second (fresh) female was introduced, 58% of the males produced at least one more ejaculation, and 17% of the males produced one further ejaculation when placed with a third female. In similar three-female tests conducted 24 hr later, all males ejaculated (M = 4 ejaculations); this level of ejaculatory output was maintained over a subsequent 10-day period of daily testing. Four ejaculations ensured a nearly 100% pregnancy rate and maximum litter size in the first females. Second and third females, however, received fewer ejaculations and subsequently showed reduced fertility and produced smaller litters. Most males showed high levels of long intromissions on all days and with all females. The physiological significance of these long intromissions may be to trigger the progestational response. Examination of the rate of recovery from sexual exhaustion indicated that 2 or 8 hr of rest resulted in fewer than 50% of the males being capable of one further ejaculation. However, most of these single ejaculations were accompanied by long intromissions and resulted in successful pregnancies. Four to eight days were required for full recovery of ejaculatory capacity. This study showed that the male golden hamster has a higher ejaculatory output and more rapid recovery from sexual exhaustion than other small rodents that have been studied. Thus, the limits of male capacity appear to vary widely among species.  相似文献   
995.
Summary Global superiority refers to the phenomenon that stimuli can be discriminated, classified, and matched faster using a global feature than a local feature. Global superiority has been shown by several authors with forms (global feature) composed of smaller forms (local features) as stimuli. In contrast, the local features used in the present study had about the same spatial extent as the global feature and each local feature was structurally relevant to the global feature. Nevertheless, global superiority was consistently observed in several classification and matching tasks. This result, together with the results of other researchers using different stimulus materials shows that global superiority is a pervasive phenomenon. Under brief exposure durations within the threshold range, local features could, however, be better discriminated than global features. This finding invalidates the perceptual explanation of global superiority that global features are faster extracted and, in this way, become available earlier than local features. Considering the magnitude of the observed differences between classification times and threshold durations of global and local features, it is argued that under normal viewing conditions global features can be better selected and utilized for the given task than local features, and that this advantage by far outweighs the faster feature extraction of local features.This research was supported by Grant Wa 419/3 from the Deutsche Forschungsgemeinschaft  相似文献   
996.
The velocities of motor and sensory conduction of median and ulnar nerves were measured on the left and right arms of 33 right-handed and 12 left-handed normal subjects. Contrary to current knowledge there was no statistically significant difference in the velocities of nerve conduction on the left and right sides of these subjects. It was suggested that the differences in the velocities of nerve conduction cannot contribute to the mechanisms of handedness.  相似文献   
997.
998.
The long term effects of Spivack and Shures' social problem-solving training were assessed and compared to an attention-placebo control. Thirty-seven preschool age children were involved in this year's long intervention project and six month follow-up. All subjects received 46 sessions of intervention by specially trained assistants. Support was found for the cognitive effectiveness of social problem-solving training with aberrant children at post test in that they gained significantly in their ability to generate alternative solutions to interpersonal problems. This differential effect was not sustained at follow-up. Blind teacher ratings of behavioral adjustment and independent observers' ratings of behavior (using a naturalistic observation scale developed for this study) revealed no significant behavioral training effects at post test or at follow-up. Findings are discussed with the suggestion that behavior change in young children may not be mediated through a strictly cognitive intervention, and may more logically require an integration of behavioral and cognitve techniques.  相似文献   
999.
The extent to which ability to access linguistic regularities of the orthography is dependent on spoken language was investigated in a two-part spelling test administered to both hearing and profoundly deaf college students. The spelling test examined ability to spell words varying in the degree to which their correct orthographic representation could be derived from the linguistic structure of English. Both groups of subjects were found to be sensitive to the underlying regularities of the orthography as indicated by greater accuracy on linguistically-derivable words than on irregular words. Comparison of accuracy on a production task and on a multiple-choice recognition task showed that the performance of both deaf and hearing subjects benefited from the recognition format, but especially so in the spelling of irregular words. Differences in the underlying spelling process for deaf and hearing spellers were revealed in an analysis of their misspellings: Deaf subjects produced fewer phonetically accurate misspellings than did the hearing subjects. Nonetheless, the deaf spellers tended to observe the formational constraints of English phonology and morphology in their misspellings. Together, these results suggest that deaf subjects are able to develop an appreciation for the structural properties of the orthography, but that their spelling may be guided by an accurate representation of the phonetic structure of words to a lesser degree than it is for hearing spellers.  相似文献   
1000.
Expressivity and sex-role identification were examined in a study of men in either same-sex or other-sex close relationships. It was hypothesized that androgynous men would be higher in expressivity than masculine men and that both would be higher than undifferentiated men, a hypothesis supported by the findings. Expressivity appeared to be associated with sex roles to a greater extent in same-sex relationships than in other-sex relationships, where additional factors were presumably associated with expressivity. Surprisingly, the feminine sex role was not associated with expressivity, although the masculine sex role was positively related to expressivity. Further analyses revealed that strength aspects of masculinity were associated with greater expressivity.  相似文献   
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