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241.
Familial clustering of a disease is defined as the occurrence of the disease within some families in excess of what would be expected from the occurrence in the population. It has been demonstrated for several cancer types, ranging from rare cancers as the adenomatosis-coli-associated colon cancer or the Li-Fraumeni syndrome to more common cancers as breast cancer and colon cancer. Familial clustering, however, is merely an epidemiological pattern, and it does not tell whether genetic or environmental causes or both in combination are responsible for the familial clustering. Familial clustering may be due to genetic predisposition to the disease, but exposure to environmental factors — shared by members of some families, but not by members of other families — may also cause familial clustering and hence mimic genetic inheritance in the study of nuclear families. Based on assumptions regarding the individual steps in the biological process starting with exposure to carcinogens and ending with death from disseminated cancer we suggest that genetic and environmental factors may both be involved in most of these steps. The present paper focuses on research methodologies necessary to discriminate between the effect of genes and family environment in the development of cancer.  相似文献   
242.
In a previous study (Hugdahl & Brobeck, 1986) it was shown that Pavlovian conditioning to an auditory verbal conditioned stimulus (CS) initially presented only to the left cerebral hemisphere was stronger than when the same CS was presented to the right hemisphere. This was followed up in the present study by controlling for the possibility that the effect was caused by laterally biased attention. The study was performed using the “dichotic extinction paradigm,” which consists of three different phases. During the habituation phase, the CS+ and CS- were presented binaurally and separated in time. During the acquisition phase, the CS+ was followed by a white-noise unconditioned stimulus (UCS). During the dichotic extinction phase, the CS+ and CS- were presented dichotically, i.e., simultaneous presentations on each trial. Half of the subjects had the CS+ in the right ear, and half had the CS+ in the left ear. Each group was further divided into two subgroups, with one subgroup instructed to attend only to the right ear input, and the other subgroup to attend only to the left ear input. During acquisition, larger electrodermal responses were obtained to the CS+ than to the CS-. During dichotic extinction, the CS+ right ear group showed superior resistance to extinction compared to the CS+ left ear group, with no effect of the manipulation of attention. The effect was, however, attenuated when levels of acquisition was used as covariates in an analysis of covariance. There were overall larger responses from the left hand recording.  相似文献   
243.
In the present experiment we report effects of cerebral asymmetry, or laterality, during classical conditioning to facial emotional stimuli. Twenty-five female subjects were presented with slides of a happy face in one visual half-field (VHF), and simultaneously a slide of an angry face in the other VHF, followed by shock as the unconditioned stimulus (UCS). To control for effects of sensitization, a new stimulus, never associated with the UCS, was introduced in the extinction phase. Dependent measures were phasic heart rate responses (HR) and skin conductance responses (SCR). The HR results showed a significant right hemisphere effect for the CS-UCS association, that was not attributable to UCS sensitization. No significant effects were found for the SCRs. The basic HR finding was a right hemisphere superiority for learning of a conditioned association.  相似文献   
244.
This paper documents a very pervasive underconfidence bias in the area of sensory discrimination. In order to account for this phenomenon, a subjective distance theory of confidence in sensory discrimination is proposed. This theory, based on the law of comparative judgment and the assumption of confidence as an increasing function of the perceived distance between stimuli, predicts underconfidence—that is, that people should perform better than they express in their confidence assessments. Due to the fixed sensitivity of the sensory system, this underconfidence bias is practically impossible to avoid. The results of Experiment 1 confirmed the prediction of underconfidence with the help of present-day calibration methods and indkated-a-good quantitative fit of the theory. The results of Experiment 2 showed that prolonged experience of outcome feedback (160 trials) had no effect on underconfidence. It is concluded that the subjective distance theory provides a better explanation of the underconfidence phenomenon than-do previous accounts in terms of subconscious processes.  相似文献   
245.
The present study concerns the distinctness of the 3-D shape-induced on flat displays by spacemodulated illumination (“shape from shading”). The displays that we used varied in structure, hue contrast, lightness contrast, and in the number of reflectance edges present. The modulations of the illumination were a square-wave grating, a gradual modulation (a blurred grating), and an “O’Brien modulation,” which combines an edge and a gradient. The displays were compared, using the paired comparison method, as to the distinctness of the perceived 3-D form. The results showed that the structure and chromatic color of the display were important factors facilitating the distinctness of the induced 3-D shape under all the modulation conditions. The results are discussed in relation to the “vector model” for color constancy, proposed in earlier papers.  相似文献   
246.
Reaction time (RT) and movement time (MT) are measured in two conditions, a key-press and a key-release condition. The latter makes a greater demand on perceptual feedback than the former. RT increases in the key-release condition and a fraction of MT denoted key-press time (KT) decreases in the key-press condition. It is argued that KT of a response button in the simple reaction-time experiment may serve as a proper measure of the motor component. The foreperiod prior to onset of the reacting stimulus affects RT, KT, and MT, suggesting that preparatory set or expectancy influences both the perceptual and motor components of simple human performance. The results indicate that the relation of RT and MT depends upon methodological conditions.  相似文献   
247.
Two experiments are reviewed that demonstrate effects of brain laterality on human classical conditioning. Pictures of facial emotional expressions were used as conditioned stimuli (CSs) together with shock as unconditioned stimulus (UCS). Bilateral electrodermal responses were recorded as dependent measures. In the first experiment, one group was conditioned to an angry face, and one group to a happy face. During extinction, the face-CSs were presented to the right hemisphere on half of the trials and to the left hemisphere on the other half of the trials. Results showed that the right hemisphere was superior in showing persisting effects of learning, and especially to the angry CS+. In the second experiment, lateralized presentations of the angry and happy faces were made during acquisition, with foveal presentations during extinction. Once again, the angry face elicited greater skin conductance responses (SCRs) during extinction in the group that had this stimulus presented to the right hemisphere during acquisition. It is concluded that emotional conditioning is differentially regulated by the two hemispheres of the brain.  相似文献   
248.
Against liberty     
Conclusion There are no private particular actions that should be altogether free of social interference. No absolute distinction can be made between types of actions affecting others and those affecting only the agent. Relative to a purpose in formulating an act of law, for instance, such a distinction can, however, be made. The idea of social freedom could therefore be thought to imply that even if there are no absolutely private particular actions, and even if society could interfere for any purpose to regulate the actions of the individual, not any reason for such interference is acceptable from the point of view of liberty. Acts of law should not be made unnecessarily inclusive with respect to their purpose and they should be designed to further public security. Not even in this weak formulation, however, can the principle of social liberty be defended against moral criticism. Some illiberal laws, in this sense, should after all be passed. Examples can be found in taxation law.The only reasonable conclusion to draw from all this is that there is no tenable principle of liberty.That there is no tenable principle of liberty does not mean that everything that has been condemned in the name of liberty should now be regarded as right. Many things said to result in a limitation of freedom could be wrong for other reasons. But probably not all of them are. So it will, I think, have some effects on our political views in general, if we accept the conclusion of this essay.  相似文献   
249.
Open Dialogue is a dialogical approach focusing on the perspectives of patients and their social networks on treatment and recovery processes. As part of a larger research project, this prospective cohort study explores what promotes and hinders the development of Open Dialogue in network meetings (ODNM) based on the experiences of thirty-seven clinicians and seven supervisors. Multistage focus group interviews were used to collect data and were analysed thematically. We generated two main themes: (1) togetherness and isolation and (2) challenging and evolving. The findings show that ODNM can be developed in public mental healthcare, but this leads to both challenges and opportunities at the organisational level, such as conflicting perspectives, the difficulty of maintaining interest in ODNM, the need for committed and involved leaders, and the growing change in the traditional view of treatment, which has made clinicians collaborate more with patients and their relatives.  相似文献   
250.
At present, early intensive behavioral intervention (EIBI) for children with autism spectrum disorders is the intervention that has the strongest empirical support. EIBI requires frequent supervision by qualified professionals. Norway, like many other countries, has a shortage of qualified supervisors, particularly in rural regions. This study used a reversal design to investigate how supervisors and supervisees perceive the quality of EIBI supervision and the local team's preparedness when supervision was provided either on-site or via videoconference. Calculations were made on how much time could be saved on travel when part of the supervision was provided via videoconference. There were no significant differences in the supervisors' and supervisees' ratings of on-site and videoconference supervision. Moreover, the supervisors found the local EIBI teams to be better prepared when supervision was provided via videoconference, and the videoconference supervision meetings were shorter. The study discusses the implications of these findings for the accessibility of EIBI and case capacity and proposes some areas for further research.  相似文献   
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