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151.
The self-reporting of cancer history is becoming increasingly important, as it frequently guides medical decision-making. We studied the accuracy of personal cancer history using a self-administered questionnaire, comparing the results with the Tumor Registry at our institution. Among 39,662 records, we identified 3614 women with a single cancer in the Tumor Registry who reported none or one cancer on their questionnaire. The sensitivity in self-reporting cancers was 85.7%, ranging from 92.1% for breast cancer to 42.9% for leukemia. The accuracy for breast cancer and Hodgkin's Lymphoma was significantly better than other cancers (p=0.00027, CI: 1.4–3.88). Analysis of patient's characteristics showed that Caucasians reported breast cancer more accurately than Asian/Pacific Islanders (p=0.008), and those with Jewish ancestry more accurately than non-Jewish (p=0.0435). These results will help us to improve data collection and thus improve medical decision-making.  相似文献   
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The basolateral complex of the amygdala (BLA) is critical for the acquisition and expression of Pavlovian fear conditioning in rats. Nonetheless, rats with neurotoxic BLA lesions can acquire conditional fear after overtraining (75 trials). The capacity of rats with BLA lesions to acquire fear memory may be mediated by the central nucleus of the amygdala (CEA). To examine this issue, we examined the influence of neurotoxic CEA lesions or reversible inactivation of the CEA on the acquisition and expression of conditional freezing after overtraining in rats. Rats with pretraining CEA lesions (whether alone or in combination with BLA lesions) did not acquire conditional freezing to either the conditioning context or an auditory conditional stimulus after extensive overtraining. Similarly, post-training lesions of the CEA or BLA prevented the expression of overtrained fear. Lastly, muscimol infusions into the CEA prevented both the acquisition and the expression of overtrained fear, demonstrating that the effects of CEA lesions are not likely due to the destruction of en passant axons. These results suggest that the CEA is essential for conditional freezing after Pavlovian fear conditioning. Moreover, overtraining may engage a compensatory fear conditioning circuit involving the CEA in animals with damage to the BLA.  相似文献   
154.
Testosterone (T) may enhance cognitive performance. However, its mechanisms are not well understood. First, we hypothesized that if T's effects are mediated in part through actions of its 5alpha-reduced metabolites, dihydrotestosterone (DHT) and/or 3alpha-androstanediol (3alpha-diol) in the hippocampus, then T, DHT, and 3alpha-diol-administration directly to the hippocampus should enhance learning and memory in the inhibitory avoidance task. In order to test this hypothesis, gonadectomized (GDX) male rats were administered T, DHT, or 3alpha-diol via intrahippocampal inserts immediately following training in the inhibitory avoidance task. We found that T tended to increase, and DHT and 3alpha-diol significantly increased, performance in the inhibitory avoidance task compared to vehicle-administered GDX rats. Second, we hypothesized that, if androgens' effects are due in part to actions of 3alpha-diol in the hippocampus, then systemic or intrahippocampal administration of 3alpha-diol should significantly enhance cognitive performance of GDX male rats. Third, we hypothesized that, if androgen metabolites can have actions at estrogen receptors (ERs) in the hippocampus, then administration of ER antisense oligonucleotides (AS-ODNs) directly to the hippocampus of GDX, 3alpha-diol replaced, rats would decrease learning in the inhibitory avoidance task. We found that intrahippocampal administration of AS-ODNs for ERbeta, but not ERalpha, significantly decreased learning and memory of 3alpha-diol replaced rats. Together, these findings suggest that T's effects to enhance learning and memory may take place, in part, through actions of its metabolite, 3alpha-diol, at ERbeta in the dorsal hippocampus.  相似文献   
155.
The present study examined expression of the immediate-early gene, c-Fos, following acquisition, 48-h (recent) recall, and 1-week (remote) recall of a socially transmitted food preference (STFP) in multiple brain regions implicated in learning and memory. In comparisons with controls, trained Long-Evans rats had increased Fos immunoreactivity in the ventral hippocampus following acquisition and recent recall. In the parahippocampal cortices, Fos was increased in the lateral entorhinal cortex after acquisition. In the orbitofrontal cortex, increased Fos immunoreactivity was observed in the lateral orbital cortex following both recent and remote recall and in the ventral orbital cortex following remote recall, indicating a role for the orbitofrontal cortex in the remote recall of STFP memory. In contrast, in the medial prefrontal cortex, increased Fos-ir was found following acquisition in the prelimbic cortex and following recent recall in the prelimbic and infralimbic cortices. No differences in Fos expression were found between trained rats and controls in the dorsal hippocampus, posterior parietal cortex, or amygdala. The present findings support a time-limited role of the hippocampus in the acquisition and recall of STFP memory and implicate neocortical regions involved in STFP acquisition, recent, and remote recall.  相似文献   
156.
To test a theoretical approach to disclosure of human immunovirus (HIV) status, 301 HIV-positive Latino gay men were interviewed using Audio-CASI (Computer Assisted Self-Interview technology with Audio enhancement). Consequence theory and social influence theory were combined to create a model of antecedents of disclosure. Results provided support for both theories. Perceived positive consequences were associated with greater disclosure to casual partners, families, and friends, whereas perceived negative consequences were associated with less disclosure to friends and family members. Social influence of peer behavioral norms was predictive of disclosure to all three target groups. Gay community social influence produced different effects on disclosure of HIV-positive status: a negative association for casual partners, a positive association for close friends, and no relationship for family members. Time since diagnosis was also predictive of disclosure.  相似文献   
157.
Growing research has examined parental accommodation among the families of children with obsessive-compulsive disorder (OCD). However, these studies have utilized a parent-report (PR) version of a measure, the Family Accommodation Scale (FAS) that has never received proper psychometric validation. In turn, previously derived subscales have been developed via clinical rather than empirical evidence. This study aims to conduct a comprehensive psychometric analysis of the FAS-PR utilizing data collected from 96 youths with OCD. Exploratory factors analysis was conducted and revealed a 12-item scale yielding two separate, yet related subscales, Avoidance of Triggers (AT) and Involvement in Compulsions (IC). Subsequent analyses revealed good internal consistency and convergent and discriminant validity. These findings suggest that future research should seek to examine factors that may impact various facets to accommodation as well as the role these facets plays in predicting treatment outcome. Limitations are discussed.  相似文献   
158.
本文是以记者鲍·阿·科萨列夫与作者对话的形式揭露伪科学家格拉博沃触目惊心的骗局以及俄罗斯高官和媒体对伪科学的支持和推波助澜。通灵术骗子,利用恐怖分子在别斯兰市制造几百名学生死亡的悲惨事件,格拉博沃之流,大行欺骗之能事,提出可以让死去的儿童复活,去骗取国家发给这些不幸父母的赔偿款。  相似文献   
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160.
Studies of ignorance-driven decision making have been employed to analyse when ignorance should prove advantageous on theoretical grounds or else they have been employed to examine whether human behaviour is consistent with an ignorance-driven inference strategy (e.g., the recognition heuristic). In the current study we examine whether - under conditions where such inferences might be expected - the advantages that theoretical analyses predict are evident in human performance data. A single experiment shows that, when asked to make relative wealth judgements, participants reliably use recognition as a basis for their judgements. Their wealth judgements under these conditions are reliably more accurate when some of the target names are unknown than when participants recognize all of the names (a "less-is-more effect"). These results are consistent across a number of variations: the number of options given to participants and the nature of the wealth judgement. A basic model of recognition-based inference predicts these effects.  相似文献   
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