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1.
Daniel Berlyne was a member of the faculty at the University of Toronto. His untimely death in 1976 at age 52 was noted by the establishment of the Berlyne Memorial Lecture to be given biennially by a distinguished psychologist. The inaugural lecture was given on 13 March 1978 by Jerome S. Bruner, Watts Professor of Psychology in Oxford University. The commemorative introduction--presented here--was by James M. Ham, Dean of the Graduate School and President-Elect of the University of Toronto (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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Early language use begins with a transactional dialog, which is initially both nonverbal and dependent on shared knowledge. As the adult caretakers update their interpretation of the child's competence and make more sophisticated demands on his/her production the child takes a more active role. Two formats provide examples of this development: (a) "Bookreading" traces the child's development from the establishment of joint reference through pointing (through the development of turntaking) to eventual introduction of words in appropriate places in the dialog. (b) "Requesting" explores the production of pragmatic and semantic features in the child's language development. Three types of requests are examined: requests for objects, for joint role enactment, and for supportive action. In each type, the child's developing knowledge of the real world determines the way he or she guides the request and aids in making more complex requests. Both examples are taken from a study of 2 mother–infant dyads in which videotape recording of free play sessions were taken at fortnightly intervals in the child's home. One child was studied from 3 to 18 mo, the other from 5 to 24 mo of age. (French summary) (40 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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An examination of phantom limb phenomena has led to 4 conclusions: The experience of a phantom limb has the quality of reality because it is produced by the same brain processes that underlie the experience of the body when it is intact; neural networks in the brain generate all the qualities of experience that are felt to originate in the body; the experience of the body has a unitary, integrated quality that includes the quality of the "self"; and the neural network that underlies the experience of the body-self is genetically determined but can be modified by sensory experience. A theory is developed to explain these conclusions. It is proposed that we are born with a widespread neural network (the "neuromatrix") for the body-self, which is subsequently modified by experience. The neuromatrix imparts a pattern on all inputs from the body, so that experiences of one's own body have a quality of self and are imbued with affective tone and cognitive meaning. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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《钢铁冶炼》2013,40(7):505-513
Abstract

Railways were originally uniquely identified with the material of their initial construction and now are technically identified by the characteristic contact of 'steel wheel on steel rail'. Over 160 years ago failures of iron railway axles led to research into what we now know as metal fatigue. Accidents throughout the ages have acted as catalysts for research and improvements: this lecture will identify some key incidents. The change from iron to steel, following Bessemer's discovery of a method of bulk production and its implementation in Sheffield, resulted in fewer materials failures and enabled greater loads to be carried at greater speeds. Today's railways rely on a wide variety of materials from all the major classes of materials. The requirements of cost, weight, reliability, crashworthiness, maintainability and inspection are often in conflict as the service loadings imposed by the modern railway on materials have become more severe. It is not therefore surprising that despite our advances in knowledge and capabilities, costly failures still occasionally occur. Nevertheless, railways have benefited from, and contributed to, advances in material engineering way beyond the initial emphasis on iron.  相似文献   

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In this lecture delivered at the University of Ontario in 1982, the author discusses the relationship of hormones to the psychological variables of perception, learning, and memory. Some examples of hormonal modification of perception include changes in food preferences, responses to sexual stimuli, and perceptual changes during the menstrual cycle. Perception may, in turn, affect hormones: A female's estrogen secretion may depend on how and how often she perceives the males around her. The effects of hormones on learning and memory are exemplified in animals in the learning that leads to the formation of permanent social bonds between mothers and their offspring. The hormonal state of the female undergoes rapid change at the end of pregnancy and immediately following parturition. Stimuli provided by the newborn are effective only during this period in animals such as sheep. However, once the mother has learned to recognize her newborn, the learning effects persist indefinitely without continuing hormonal support. Hormonal facilitation of memory occurs in some male birds when they first begin to sing. The hormone is not necessary for original learning, but it does influence activation of the putative memory trace. In turn, memory can inhibit or stimulate secretion of hormones. The author suggests that in investigations of complex behavior, psychological processes should be explored as mediators between hormones and behavior. (French abstract) (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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This review explores evidence for the reversibility of atherosclerosis and augmentation of angiography with non-invasive arterial wall imaging. Meta-analysis from coronary angiographic trials demonstrates that regression and stabilization are 1.5 to 2 times more common in treated than placebo subjects, and progression is reduced by half in treated subjects. Odds ratios for clinical coronary events are significantly reduced with treatment. Lesion improvement occurs more readily in women than men and more so in women receiving concomitant estrogen replacement therapy. Lesions with > or = 50% diameter stenosis (%S) at baseline respond more readily to lipid lowering than those < 50% S, whereas reduction in coronary events is related to stabilization of lesions < 50% S. Lipoproteins have a differential effect on lesion progression according to lesion size, and triglyceride-rich lipoproteins play an important role in the progression of coronary artery lesions < 50% S. Improved therapeutic regimens to alter progression of atherosclerosis may require adjunctive therapy, such as with antioxidants or hormone replacement therapy, in concert with low-density lipoprotein cholesterol reduction to prevent new lesion formation or early lesion progression. Sequential coronary angiographic determination of progression evaluated by both quantitative coronary angiography and global change score, a visual assessment of overall lesion change, predicts clinical coronary events. Only inferences about the state of the arterial wall can be made from angiography, because it delineates only the lumen. Therapy testing and study of atherosclerosis progression can be improved with noninvasive B-mode ultrasonographic imaging of the distal common carotid artery far-wall intima-media thickness (IMT), a reliable measure of early preintrusive atherosclerosis. Measurement of common carotid IMT is useful for the study of coronary artery risk factors and can augment studies of coronary artery intrusive lesions, because it is associated with coronary artery disease. B-mode measurement of common carotid IMT has the potential of serving as a noninvasive surrogate end point for clinical coronary events. Screening for peripheral vessel changes indicative of high risk for coronary artery disease is possible and cost-effective with the noninvasive procedures now available.  相似文献   

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The skeleton consists of a series of elements with a variety of functions. In locations such as the skull, where shape or protection are of prime importance, the bone's architecture is achieved during growth under predominant genetic control. In locations such as the limbs, where the ability to withstand repetitive loading is important, only the general form of the bone will be achieved as a result of growth alone, the remaining characteristics resulting from an adaptive response to functional load bearing. In the horse, this functional load-bearing will be provided by the animal's natural activity pattern in box or paddock supplemented by the specific activities of the training regimen. It is the adaptive response to the total activity pattern that influences bone modelling and remodelling and so determines the bone's architecture. The objective of the training regimen is to ensure that this response achieves an appropriate match between bone architecture and the loads it is required to withstand during both training and athletic performance. We propose that for the match between architecture and load-bearing to be established, and maintained, subsequently, bone cells must be able to 'assess' directly or indirectly the functional strains produced within the bone tissue. Because these strains are used as feedback they are both the objective of functionally adaptive modelling and remodelling, and the stimulus for its control. The mechanisms whereby bone cells control skeletal modelling and remodelling to produce a functionally competent skeleton are unknown although some of the factors and sequence of events involved are presented here. The extent to which variation in training regimen affects bone architecture has not been studied systematically in any species.  相似文献   

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Tissue factor pathway inhibitor (TFPI) is known to inhibit the initial reaction in the tissue factor-mediated coagulation pathway. We measured plasma free-form TFPI antigen levels and monitored 24-h Holter recordings at 06.00, 14.00 and 22.00 h in 15 patients with coronary spastic angina, 13 patients with stable exertional angina, and 11 control subjects. There was a significant circadian variation in plasma free-form TFPI antigen levels in patients with coronary spastic angina (25.8+/-2.0 ng/ml at 06.00 h, 21.1+/-1.6 ng/ml at 14.00 h, and 20.2+/-1.4 ng/ml at 22.00 h; p<0.01). Furthermore, free-form TFPI antigen levels at 06.00 h were significantly higher in coronary spastic angina patients than in patients with stable exertional angina or control subjects (p<0.01). Free-form TFPI antigen levels increased after the ischemic attacks in coronary spastic angina (p<0.01). This circadian variation correlated with the frequency of attacks, with the peak level occurring between midnight to early morning in patients with coronary spastic angina.  相似文献   

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The processes of differentiation and tumorigenesis have been long thought to be connected. The recent identification of Patched, a gene essential for Drosophila embryonic development, as a tumor suppressor has focused attention on the concept that tumorigenesis involves abnormalities of development. In fact, a large number of genes in the signalling pathway of the Patched gene are either tumor suppressors or oncogenes. This supports the concept that growth control is a critical requirement of differentiation, and that aberrant cellular development can contribute to malignancy. Whereas the identification of genes that result in dominantly inherited cancer syndromes has played a vital role in understanding cancer, the vast majority of "sporadic" cancers have properties of a complex genetic disease. Approaches to identify common alleles in cancer-associated genes promise to increase our understanding of the disease and aid the rational design of preventative and therapeutic strategies.  相似文献   

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PURPOSE: To trace the evolution and status of our knowledge of choroidal melanoma with regard to the nature, cause, and treatment of this tumor. METHODS: Historical materials beginning with Georg Bartisch's contributions in 1583 through to the Collaborative Ocular Melanoma Study and recent basic research are reviewed. RESULTS: Many individuals have made important contributions to our knowledge about this tumor. Basic information, however, regarding the natural history of the tumor, the most effective treatment, and its cause is lacking. CONCLUSION: The Collaborative Ocular Melanoma Study will provide important information regarding the choice of treatment between enucleation and radiotherapy as well as natural history information, quality of life, and definitive pathology findings. Definitive treatment of choroidal melanoma will depend on knowledge of the genetic defects that cause the tumor. Within the next 25 years, it is predicted that genetic defects will be determined and tumor samples will be obtained using small-needle aspiration and DNA probes located on microchips. In addition, treatment will then be based on drugs designed to inhibit molecules related to the genetic defect in the tumor.  相似文献   

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Carboplatin is a better-tolerated alternative to cisplatin. JM216, the first p.o.-administrable platinum complex possesses toxicities comparable to carboplatin in Phase I studies. Together with the trans-platinum complex JM335, it provides new chemical guidelines for the development of compounds that may circumvent cisplatin resistance in tumors. Systematic structure-activity investigations have led to the discovery and development of ZD1694 (Tomudex), an inhibitor of thymidylate synthase that exploits both the reduced folate carrier and folylpolyglutamate synthetase as major determinants of its growth-inhibitory activity. Phase II studies have revealed encouraging activity against colon cancer, and Phase III studies are nearing completion. An associated structure-activity investigation has led to the development of ZD9331, a potent thymidylate synthase inhibitor which exploits the reduced folate carrier for cell entry, but which is independent of polyglutamation for its thymidylate synthase-inhibitory activity. This compound possesses antitumor activity in vivo and has been selected for full development.  相似文献   

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Emphasizes that family stress is not an event or internal state but an ongoing process that especially affects and is affected by individuals' personal and social resources. This process entails both objective and subjective factors. However, the authors argue that the subjective factors are largely a product of the actual event. This differs from others who accentuate individual differences rather than classes of differences that are common to like stressful circumstances. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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