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891.
Whether lung transplantation improves Health-related Quality of Life in patients with emphysema and other end-stage lung diseases before and after lung transplantation was examined. Between 1992 and 1999, 23 patients with emphysema and 19 patients with other indications completed self-administered questionnaires before lung transplantation, and at 4, 7, 13, and 25 mo. after transplantation. The questionnaire included the Nottingham Health Profile, the State-Trait Anxiety Inventory, the Self-rating Depression Scale, the Index of Well-being, the self-report Karnofsky Index, and four respiratory-specific questions. Neither before nor after transplantation were significant differences found on most dimensions of Health-related Quality of Life between patients with emphysema and other indications. Before transplantation, both groups report major restrictions on the dimensions Energy and Mobility of the Nottingham Health Profile, low experienced well-being, depressive symptoms, and high dyspnea. About 4 mo. after transplantation, most Health-related Quality of Life measures improved significantly in both groups. These improvements were maintained in the following 21 mo.  相似文献   
892.
Using three different samples of couples (clinic, nondistressed community, and engaged), we found that 15 minutes was sufficient to witness enough behavior to make reliable (i.e., internally consistent) estimations of most Rapid Marital Interaction Coding System (Heyman & Vivian, 1993) code frequencies. Ten minutes is sufficient for many codes of interest. The ease in which "how much time is necessary" calculations can be made should entice behavioral investigators from a variety of content areas to publish such figures. By empirically investigating a factor that in most fields becomes reified through convention, investigators can conduct observational research that is both maximally efficient and maximally scientifically defensible.  相似文献   
893.
Alzheimer’s disease (AD) and diabetes rarely occur together, a finding that provides a possible clue as to the development of AD. Abnormal glucose metabolism is not limited to diabetes, but also can include impaired glucose tolerance, insulin resistance, and hyperinsulinemia. AD patients have significantly varying insulin levels after drinking sugared sodas and thus may be classified as insulin resistant. After reviewing the literature on impaired glucose tolerance and insulin production in AD, we present several hypotheses as possible explanations for the relationship between insulin resistance and AD. Finally, we suggest future studies, including studies on use of thiazolidinediones (currently used in the treatment of diabetes) in AD.  相似文献   
894.
What Moore's Paradox Is About   总被引:2,自引:0,他引:2  
On the basis of arguments showing that none of the most influential analyses of Moore's paradox yields a successful resolution of the problem, a new analysis of it is offered. It is argued that, in attempting to render verdicts of either inconsistency or self-contradiction or self-refutation, those analyses have all failed to satisfactorily explain why a Moore-paradoxical proposition is such that it cannot be rationally believed. According to the proposed solution put forward here, a Moore-paradoxical proposition is one for which the believer can have no non-overridden evidence. the arguments for this claim make use of some of Peter Klein's views on epistemic defeasibility. It is further suggested that this proposal may have important meta-epistemological implications.  相似文献   
895.
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897.
In this paper we present four case studies of adult women from working class backgrounds who attended Hillside College (a pseudonym for one of the seven-sister colleges) during the early 1990s. Although research on women has led, over the past few decades, to a more complex picture of the contexts in which women develop their identities, one important context that has been underexplored is social class. Drawing on data from three lengthy interviews with each of our four participants, our purpose was to explore the identity concerns of adult women from working class backgrounds in their experience getting to and attending Hillside College, which has historically been home to the middle and upper social classes. Implications for college retention are discussed.  相似文献   
898.
Classical conditioning has been explained by two main types of theories that postulate different learning mechanisms. Rescorla and Wagner (1972) put forth a theory in which conditioning is based on the ability of the US to drive learning through error correction. Alternatively, Mackintosh (1973) put forth a theory in which the ability of the CS to be associated with the unconditioned stimulus is modulated. We have proposed a reconciliation of these two mechanisms as working in parallel within different neural systems: a cerebellar system for US modulation and a hippocampal system for CS modulation. We developed a computational model of cerebellar function in eyeblink conditioning based on the error correction mechanism of the Rescorla-Wagner rule in which learningrelated activity from the cerebellum inhibits the inferior olive, which is the US input pathway to the cerebellum (Gluck et al., 1994). We developed a computational model of the hippocampal region that forms altered representations of conditioned stimuli based on their behavioral outcomes (Gluck & Myers, 1993; Myers et al., 1995). Overall, computational modeling and empirical findings support the idea that, at least in the case of eyeblink conditioning, there may be two different neural systems: the cerebellum which mediates US-based error correction and hippocampus which alters representations of CSs.  相似文献   
899.
The Internet has been exploited successfully in the past as a medium for behavioral research. This paper presents a series of studies designed to assess Internet-based measures of drivers’ risk-taking behavior. First, we compared responses from an Internet sample with a traditional pencil-and-paper sample using established questionnaire measures of risk taking. No significant differences were found. Second, we assessed the validity of new Internet-based instruments, involving photographs and photographic animations, that measured speed, gap acceptance, and passing. Responses were found to reflect known demographic patterns of actual behavior to some degree. Also, a roadside survey of speeds was carried out at the locations depicted in the photographic measure of speeding and, with certain exceptions, differences between the two appeared to be constant. Third, a between-subject experimental manipulation involving the photographic animation measure of gap acceptance was used to demonstrate one application of these techniques.  相似文献   
900.
High levels of false recognition are observed after people study lists of semantic associates that all converge on a nonpresented lure word. In previous experiments, we have found that orienting participants to encode distinctive information about study list items by presenting them as pictures as opposed to words produces marked reductions in false recognition. We have suggested that these reductions reflect the operation of a distinctiveness heuristic: Participants demand access to detailed pictorial information in order to support a positive recognition decision. The present experiments provide additional evidence on this point and allow us to distinguish between the distinctiveness heuristic account and an alternative account based on the impoverished encoding of relational information that occurs when one is studying pictures. In Experiment 1, even when only half of the items in a study list were presented as pictures, a general suppression of false recognition was observed that could be attributable to impoverished encoding of relational information. Experiment 2 provided a critical test of the distinctiveness heuristic account: We manipulated test instructions and found that differences in false recognition rates between picture and word encoding were attenuated in a retrieval condition that did not encourage reliance on a distinctiveness heuristic.  相似文献   
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