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171.
These cancer genetic counseling recommendations describe the medical, psychosocial, and ethical ramifications of identifying at-risk individuals through cancer risk assessment with or without genetic testing. They were developed by members of the Practice Issues Subcommittee of the National Society of Genetic Counselors Cancer Genetic Counseling Special Interest Group. The information contained in this document is derived from extensive review of the current literature on cancer genetic risk assessment and counseling as well as the personal expertise of genetic counselors specializing in cancer genetics. The recommendations are intended to provide information about the process of genetic counseling and risk assessment for hereditary cancer disorders rather than specific information about individual syndromes. Key components include the intake (medical and family histories), psychosocial assessment (assessment of risk perception), cancer risk assessment (determination and communication of risk), molecular testing for hereditary cancer syndromes (regulations, informed consent, and counseling process), and follow-up considerations. These recommendations should not be construed as dictating an exclusive course of management, nor does use of such recommendations guarantee a particular outcome. These recommendations do not displace a health care provider's professional judgment based on the clinical circumstances of a client.  相似文献   
172.
A number of lines of study suggest that word meanings are not always fully exploited in comprehension. In two experiments, we used a text-change paradigm to study depth of semantic processing during reading. Participants were instructed to detect words that changed across two consecutive presentations of short texts. The results suggest that the full details of word meanings are not always incorporated into the interpretation and that the degree of semantic detail in the representation is a function of linguistic focus. The results provide evidence for the idea that representations are only good enough for the purpose at hand (Ferreira, Bailey, & Ferraro, 2002).  相似文献   
173.
Structural equation mixture modeling (SEMM) integrates continuous and discrete latent variable models. Drawing on prior research on the relationships between continuous and discrete latent variable models, the authors identify 3 conditions that may lead to the estimation of spurious latent classes in SEMM: misspecification of the structural model, nonnormal continuous measures, and nonlinear relationships among observed and/or latent variables. When the objective of a SEMM analysis is the identification of latent classes, these conditions should be considered as alternative hypotheses and results should be interpreted cautiously. However, armed with greater knowledge about the estimation of SEMMs in practice, researchers can exploit the flexibility of the model to gain a fuller understanding of the phenomenon under study.  相似文献   
174.
Most psychosocial research on attention-deficit/hyperactivity disorder (ADHD) has focused on deficits in school, family, or behavioral functioning without incorporating perceived quality of life (QoL) or the adolescents' perspective. The Youth Quality of Life Instrument--Research Version (YQOL-R), was used to assess self-perceived QoL in a community sample of adolescents aged 11-18 years. Fifty-five adolescent males with a clinical diagnosis of ADHD were compared to a group of 107 adolescents with no chronic conditions (NCC) and a group of 52 adolescents with mobility impairments (MI). The adolescents with ADHD reported significantly lower perceived QoL scores, particularly in the Self and Relationship domains, than the NCC group. Their scores were similar to those from the group with MI, a group previously shown to have a substandard QoL. Interventions to improve self-esteem and social interactions might use QoL outcomes in evaluating effectiveness.  相似文献   
175.
Kwan P  Brodie MJ 《CNS spectrums》2004,9(2):110-119
Although modern community-based studies have shown that a majority of people with newly diagnosed epilepsy will enter long-term remission, seizures remain refractory to treatment in a substantial proportion of this population--perhaps as much as 40%. A consensus is being reached that, for operational purposes, pharmacoresistance can be suspected when two appropriately chosen, well-tolerated, first-line antiepileptic drugs (AEDs) or one monotherapy and one combination regimen have failed due to lack of efficacy. Poor prognostic factors include lack of response to the first AED, specific syndromes, symptomatic etiology, family history of epilepsy, psychiatric comorbidity, and high frequency of seizures. These observations suggest that prognosis can often be determined early in the course of the disorder. We propose a management paradigm that aims to maximize the chance of successful AED therapy, including the early use of "rational polytherapy" for patients not responding to monotherapy, and to identify efficiently patients suitable for "curative" resective surgery, in particular those with mesial temporal lobe epilepsy. An orderly approach to each epilepsy syndrome will optimize the chance of perfect seizure control and help more patients achieve a fulfilling life.  相似文献   
176.
Children are nearly as sensitive as adults to some cues to facial identity (e.g., differences in the shape of internal features and the external contour), but children are much less sensitive to small differences in the spacing of facial features. To identify factors that contribute to this pattern, we compared 8-year-olds' sensitivity to spacing cues with that of adults under a variety of conditions. In the first two experiments, participants made same/different judgments about faces differing only in the spacing of facial features, with the variations being kept within natural limits. To measure the effect of attention, we reduced the salience of featural information by blurring faces and occluding features (Experiment 1). To measure the role of encoding speed and memory limitations, we presented pairs of faces simultaneously and for an unlimited time (Experiment 2). To determine whether participants' sensitivity would increase when spacing distortions were so extreme as to make the faces grotesque, we manipulated the spacing of features beyond normal limits and asked participants to rate each face on a "bizarreness" scale (Experiment 3). The results from the three experiments indicate that low salience, poor encoding efficiency, and limited memory can partially account for 8-year-olds' poor performance on face processing tasks that require sensitivity to the spacing of features, a kind of configural processing that underlies adults' expertise. However, even when the task is modified to compensate for these problems, children remain less sensitive than adults to the spacing of features.  相似文献   
177.
Three experiments revealed that memory for verbs is more dependent on semantic context than is memory for nouns. The participants in Experiment 1 were asked to remember either nouns or verbs from intransitive sentences. A recognition test included verbatim sentences, sentences with an old noun and a new verb, sentences with an old verb and a new noun, and entirely new sentences. Memory for verbs was significantly better when the verb was presented with the same noun at encoding and at retrieval. This contextual effect was much smaller for nouns. Experiments 2 and 3 replicated this effect and provided evidence that context effects reflect facilitation from bringing to mind the same meaning of a verb at encoding and at retrieval. Memory for verbs may be more dependent on semantic context because the meanings of verbs are more variable across semantic contexts than are the meanings of nouns.  相似文献   
178.
A meta-analytic review of prospective memory and aging   总被引:16,自引:0,他引:16  
A meta-analysis of prospective memory (PM) studies revealed that in laboratory settings younger participants outperform older participants on tests of both time- and event-based PM (rs=-.39 and -.34, respectively). Event-based PM tasks that impose higher levels of controlled strategic demand are associated with significantly larger age effects than event-based PM tasks that are supported by relatively more automatic processes (rs=-.40 vs. -.14, respectively). However, contrary to the prevailing view in the literature, retrospective memory as measured by free recall is associated with significantly greater age-related decline (r=-.52) than PM, and older participants perform substantially better than their younger counterparts in naturalistic PM studies (rs=.35 and.52 for event- and time-based PM, respectively).  相似文献   
179.
Despite considerable evidence that psychopathic criminals are deviant in their emotional reactions, few studies have examined responses to both pleasurable and aversive stimuli or assessed the role of different facets of psychopathy in affective deviations. This study investigated physiological reactions to emotional sounds in prisoners selected according to scores on the 2 factors of Hare's Psychopathy Checklist--Revised (PCL-R; R. D. Hare, 1991). Offenders high on the PCL-R emotional-interpersonal factor, regardless of scores on the social deviance factor, showed diminished skin conductance responses to both pleasant and unpleasant sounds, suggesting a deficit in the action mobilization component of emotional response. Offenders who scored high only on the social deviance factor showed a delay in heart rate differentiation between affective and neutral sounds. These findings indicate abnormal reactivity to both positive and negative emotional stimuli in psychopathic individuals, and suggest differing roles for the 2 facets of psychopathy in affective processing deviations.  相似文献   
180.
We studied simulated MMPI-2 (Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989) code type stability and change expected with measurement error for 12 MMPI-2 well-defined mean code type profiles. Profile scores for the 2 scales defining the code type were systematically varied to represent target code type profiles at 9 different levels of T-score profile definition. We randomly generated samples of 50 simulated, estimated true score profiles at each level of profile definition for each code type around the estimated true scores for each scale at each level of profile definition. Two sets of simulated profiles were developed. The first simulation was based on the reported means, test-retest reliabilities, and the standard errors of measurement for the MMPI-2 normative group. The second simulation was based on the means, standard deviations, and estimated retest stability for a clinical group of psychiatric patients. We calculated frequencies and percentages of simulated profiles with the highest estimated true scores on the same 2 scales as the original code type profile. Percentages of simulated profiles with the same 2 highest scales as the original code type profiles increased from 27% to 37% for the 3-point level of definition, 37% to 49% for the 5-point definition, 46% to 61% for 7-point definition, 63% to 78% for 10-point definition, 78% to 89% for 13-point definition, 83% to 93% for 15-point definition, and greater than 90% for profile definition greater than 15 points.  相似文献   
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