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911.
荷包牡丹碱对受低强度训练的小鸡的记忆形成的影响   总被引:1,自引:1,他引:0  
在小鸡一次性被动回避行为中,低强度训练的动物其长时记忆保持不良,而训练前10或20分钟注射γ-氨基丁酸能颉颃剂荷包牡丹碱,可明显提高长时记忆的保持水平,这一作用可被激动剂蝇蕈碱反转。记忆保持曲线进一步显示,受低强度训练的动物其记忆仅能保持至训练后20分钟,而注射荷包牡丹碱可使记忆至少延长至训练后120分钟。上述结果提示:小鸡的记忆形成受γ-氨基丁酸能系统的调节;γ-氨基丁酸能系统虽然直接参与中时记忆,但对长时记忆的形成似乎也是必需的。  相似文献   
912.
We examined interrelationships among personal, family, and prior service utilization data collected on young people selected to participate in a Chicago suburban area system of care, with a detailed consideration of a subset of 176 White participants aged 9–20 years. Data obtained through a review of archival information and then analyzed included WISC IQ grade retention, medication status, DSM diagnostic group, adjudication, marital status of parents, living situation before selection, maternal employment, public assistance status, family risk status, and placement history. Results showed that IQ and specific DSM diagnostic category were not important correlates of personal, family, or placement variables, although having a DSM diagnosis of any kind was. Family risk factors, including family history of mental illness, substance abuse, criminal conviction, and violence in the family, were related to other family variables, primarily. Adjudication and prescribed medication appeared to have been alternative responses to these young people's problems. A cluster analysis of these system of care participants' placement histories indicated five clusters characterized by varied personal and family correlates, as well as different patterns of placement usage.  相似文献   
913.
James S. Nelson 《Zygon》1999,34(1):45-50
This study attempts to show that brain research brings to light religious meanings. There is a physical basis of religion in that the way the brain has evolved makes possible the religious meanings of human experience. The brain grows out of and reflects the universe. The brain is an icon of God. In the analysis of the brain's various parts and functions the relational dimensions of reality are uncovered in their physical basis. This points to ultimate reality as social and to a social God. As such, the structures of reality, experienced through the brain, reflect the reality of God.  相似文献   
914.
现行的医疗纠纷技术鉴定模式年来在解决医疗纠纷中起到了重要作用,但随着卫生改革的进一步深化和法制的日趋健全,以及人们法律意识的不断提高它的缺陷也日益突出。应当建立新的医疗技术鉴定管理体制,鉴定委员会的人员鸺成,增强医疗技术透明度,建立时效制度和回避制度。  相似文献   
915.
肿瘤是当今人类生命健康的主要威胁之一。致癌基因与遗传背景和肿瘤的形成有密切关系。致癌基因与遗传背景,致癌基因与抗癌基因之间的时空结构和非线性作用都有可能使正常细胞恶变,导致肿瘤的形成。致癌基因与遗传背景实际上构成了细胞中的一个完整的遗传系统。本文试图用系统方法探讨两者的相互作用,以便更好地探讨肿瘤发生的机理和治疗手段。  相似文献   
916.
One-hundred-and-sixty adolescents participated in two studies designed to investigate the relationship between IE and helping behavior as mediated by the perceived cause of another's need. In the first study, Ss were given the opportunity to help, either “indirectly” or “directly,” a supervisor who had been over- or underpaid in a prior similar task. Internals helped more in the “direct” help than the “indirect” help conditions but their helping behavior and their perceptions of their supervisors were not consistent. The perceptions of the externals were relatively consistent with their greater help of the “overpaid” supervisor. In study 2, the Ss were given additional information to increase the possibility of their making causal attributions as a function of the supervisor's prior fate. Once again, the external subjects' helping behavior reflected their perception of their supervisor's merit. The internal subjects exhibited relatively little helping behavior regardless of their supervisors' prior fate or perceived competence.  相似文献   
917.
Behavior is treated as basic physics. Dimensions are identified and their transformations from physical specification to axes in behavioral space are suggested. Responses are treated as action patterns arrayed along a continuum of activation energy. Behavior is seen as movement along a trajectory through this behavior space. Incentives or reinforcers are attractors in behavior space, at the centers of basins of lowered potential. Trajectories impinging on such basins may be captured; repeated capture will warp the trajectory toward a geodesic, a process called conditioning. Conditioning is enhanced by contiguity, the proximity between the measured behavior and the incentive at the end of the trajectory, and by contingency, the depth of the trajectory below the average level of the potential energy landscape. Motivation is seen as the potential of an organism for motion under the forces impinging on it. Degree of motivation is characterized by the depth of the potential field, with low motivation corresponding to a flat field and a flat gradient of activation energy. Drives are the forces of incentives propagated through behavior space. Different laws for the attenuation of drive with behavioral distance are discussed, as is the dynamics of action. The basic postulate of behavior mechanics is incentive-tracking in behavior space, the energy for which is provided by decreases in potential. The relation of temporal gradients to response differentiation and temporal discrimination is analyzed. Various two-body problems are sketched to illustrate the application of these ideas to association, choice, scalar timing, self-control, and freedom.  相似文献   
918.
We developed a video system for real-time detection of a pigeon's orientation and for reinforcement of a “turning response.” Using this system, negative behavioral contrast was found across key-peck and turning responses. In addition, turning away from the pecking key was detected by the system just after presentation of the negative discriminative stimulus on the key. The results suggest that avoidance of the discriminative stimulus in the constant component, which has been regarded as a causal factor for negative contrast (additivity theory), is not the primary factor for negative behavioral contrast of pigeons' key pecking, but may account for negative local contrast.  相似文献   
919.
In the XVIIth century the conflict which opposed the jansenists to the jesuits involved the problem of the due process in theological matter. The jesuits heralded the thesis that the infallibility of the Church has to be extended from dogmatics (quaestio iuris) to the historical facts (quaestio facti). On the opposite side Arnauld maintained that such an opinion was monstruous: also in religious matters the fact has to be proved according to the principles of a due process, and not by authority. In this article the thesis pleaded by the jansenists is considered in connection with the model of argumentative procedure offered by the Port-Royal logic.The Logique ou Art de penser (1622) by Antoine Arnauld and Pierre Nicole seems to have rediscovered the classical principles of the theory of argumentation: from the burden of proof to the idea of probable truth. But really a new model of adversary-system has been introduced into the modern mind, which is very different in concept from the topical tradition. The basic metaphor of combat, implying that the truth will prevail in the fight, is compatible with the epistemological premises of the modern logic (as the separation between fact and value). Therefore the problem of the fact-finding seems to be attracted into the area of the logic of information, and not of the theory of argumentation.
  相似文献   
920.
This study compared the effects of self-evaluation and adult-dispensed tokens on room-cleaning behavior of six predelinquent youths in a residential token-economy setting. The self-evaluation token system proved to be as effective as the external adult-administered system in increasing room-cleaning behavior and was more effective in maintaining performance after contingencies were withdrawn. The self-evaluation token system increased resistance to extinction, compared to the external token system, and appeared to be a useful component for a traditional token-economy system.  相似文献   
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