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911.
Genetic testing for BRCA1/2 mutations associated with hereditary breast and ovarian cancer reveals significant risk information about one's chances of developing cancer. It is important to study communication processes in families where members are undergoing genetic testing because the information received is crucial not just to the individual concerned but also to other members of the biological family. This study investigates family communication of BRCA1/2 test results from both the informants' and recipients' perspectives. A total of 10 female patients and 22 of their relatives were interviewed. Patients' and their relatives described feelings of responsibility for sharing genetic information within the family to enable others to reduce their risks of developing cancer. However, there were limits to an individuals' responsibility once key family members had been informed, who then had to take responsibility for continuing dissemination of information. Whilst there was an implicit responsibility to inform the family of a mutation, information was edited or withheld in the best interest of relatives, dependent upon their perceived emotional readiness, resilience and current life stage and circumstances. The pre-existing family culture and the impact previous cancer diagnoses had upon the family also influenced the process of communication. Findings are discussed in relation to extant literature and implications for clinical practice are considered. 相似文献
912.
913.
Source monitoring refers to mental processes leading to attributions regarding the origin of information. We tested Johnson, Hashtroudi, and Lindsay's (1993) assumption that prior source-relevant knowledge is used in some source-monitoring tasks. In two experiments using different domains of schematic knowledge, two sources presented information that was expected for one source and somewhat unexpected for the other. In a later source-monitoring test, participants decided whether items had been presented by Source A, by Source B, or were new. The results of both experiments show that source identification is better for expected items than for somewhat unexpected items. Multinomial modeling analyses revealed that when participants do not remember the source of information, they guess that it was presented by the expected source. These results provide evidence for the claim that source monitoring can be based on prior knowledge and support a guessing hypothesis. 相似文献
914.
Bourtchouladze R Patterson SL Kelly MP Kreibich A Kandel ER Abel T 《Learning & memory (Cold Spring Harbor, N.Y.)》2006,13(6):745-752
The cAMP/PKA pathway plays a critical role in learning and memory systems in animals ranging from mice to Drosophila to Aplysia. Studies of olfactory learning in Drosophila suggest that altered expression of either positive or negative regulators of the cAMP/PKA signaling pathway beyond a certain optimum range may be deleterious. Here we provide genetic evidence of the behavioral and physiological effects of increased signaling through the cAMP/PKA pathway in mice. We have generated transgenic mice in which the expression of a constitutively active form of Gsalpha (Gsalpha* Q227L), the G protein that stimulates adenylyl cyclase activity, is driven in neurons within the forebrain by the promoter from the CaMKIIalpha gene. Despite significantly increased adenylyl cyclase activity, Gsalpha* transgenic mice exhibit PKA-dependent decreases in levels of cAMP due to a compensatory up-regulation in phosphodiesterase activity. Interestingly, Gsalpha* transgenic mice also exhibit enhanced basal synaptic transmission. Consistent with a role for the cAMP/PKA pathway in learning and memory, Gsalpha* transgenic mice show impairments in spatial learning in the Morris water maze and in contextual and cued fear conditioning tasks. The learning deficits observed in these transgenic mice suggest that associative and spatial learning requires regulated Gsalpha protein signaling, much as does olfactory learning in Drosophila. 相似文献
915.
916.
Bowen DJ Burke W Culver JO Press N Crystal S 《Cultural diversity & ethnic minority psychology》2006,12(1):45-56
The goal of this study was to determine whether genetic counseling or psychosocial group counseling provided to Ashkenazi women can reduce breast cancer worry, cancer risk perception, and interest in having genetic testing. Women (N=211) were randomized to receive individual genetic risk counseling, to receive a group psychosocial group counseling, or to serve as a control group. The authors found that both counseling methods reduced cancer worry, lowered perceptions of breast cancer risk, and decreased interest in having genetic testing. Counseling can help women gain a more accurate perception of their risk, expose them to the benefits and limitations of genetic testing, and reduce their worry about cancer. 相似文献
917.
918.
There is increasing evidence that animals can learn abstract spatial relationships, and successfully transfer this knowledge to novel situations. In this study, rufous hummingbirds (Selasphorus rufus) were trained to feed from either the lower or the higher of two flowers. When presented with a test pair of flowers, one of which was at a novel height, they chose the flower in the appropriate spatial position rather than the flower at the correct height. This response may also have been influenced by a preference for taller flowers as acquisition of the task during experimental training occurred more readily when the reward flower was the taller of the pair. Thus, it appears that although learning abstract relationships may be a general phenomenon across contexts, and perhaps across species, the ease with which they are learned and the context in which they are subsequently used may not be the same. 相似文献
919.
920.
Differentiating between additive (quantitative) and interactive (qualitative) effects of comorbidity has important treatment implications. This study illustrates the heuristic superiority of a multifactorial approach over simple group comparisons in testing quantitative versus qualitative models of comorbidity. Analysis of variance was used to compare 266 adolescent inpatients identified as depressed, externalizing, both, or neither on self-report measures of personality, school problems, and substance abuse. The results support quantitative rather than qualitative models of comorbidity. Depressed status related most strongly to group differences in interpersonal and self-critical concerns. Externalizing status related most strongly to group differences in school problems and drug use. Main effects for the two statuses together explained especially elevated levels of reactance and alcohol abuse among the comorbid adolescents. 相似文献