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951.
952.
Ricker C Lagos V Feldman N Hiyama S Fuentes S Kumar V Gonzalez K Palomares M Blazer K Lowstuter K MacDonald D Weitzel J 《Journal of genetic counseling》2006,15(6):505-514
Background: Cancer genetic counseling and testing is a standard of care option for appropriate families and can identify individuals at increased risk prior to diagnosis, when prevention or detection strategies are most effective. Despite documented efficacy of cancer risk reduction in high-risk individuals, underserved and minority individuals have a disproportionate cancer burden and limited access to genetic counseling. Methods: A needs assessment survey documented gaps in knowledge and interest in prevention. Satellite clinics were established at two indigent healthcare systems. Cancer genetics CME lectures were conducted and referral guidelines disseminated to clinicians who referred patients for counseling. Results: An increase in clinician knowledge was demonstrated post-CME and reflected by quality referrals. Eighty-eight percent of patients kept their appointments. In the predominantly Latina6 (n=77) clinic population, 71.4% were affected with cancer, and 17 mutation positive families were identified. Preliminary data shows a positive impact on patients' motivation and behavior. The majority has expressed satisfaction and reduction in anxiety. Conclusions: This study demonstrates feasibility and acceptability of cancer genetics services in this population, suggesting the potential to reduce cancer morbidity in underserved, high-risk families.“Latino” is the most common census term for individuals of Spanish, Mexican, Central and South American, Cuban, or Puerto Rican descent, referring to ethnicity, and is generally considered a more ethnically/culturally based term for individuals of the aforementioned groups. As this cohort is female the feminine noun “Latina” is used 相似文献
953.
Is memory temporally organized? According to temporal distinctiveness models of memory, temporally isolated items should be better remembered than temporally crowded items in free recall tasks. Here, we tested this class of model by varying the temporal isolation of items either predictably (Experiment 1) or unpredictably (Experiment 2) in a free recall task. In both experiments, item recall probability increased as a function of the temporal gaps both before and after the item. The results are taken as support for temporal distinctiveness models of memory, in which items are represented and recalled in terms of their positions along a temporal dimension. 相似文献
954.
It is well established that rote rehearsal plays a key role in serial memory for lists of verbal items. Although a great deal
of research has informed us about the nature of verbal rehearsal, much less attention has been devoted to rehearsal in serial
memory for visual-spatial information. By using the dot task—a visual-spatial analogue of the classical verbal serial recall
task—with delayed recall, performance and eyetracking data were recorded in order to establish whether visual-spatial rehearsal
could be evidenced by eye movement. The use of eye movement as a form of rehearsal is detectable (Experiment 1), and it seems
to contribute to serial memory performance over and above rehearsal based on shifts of spatial attention (Experiments 1 and
2). 相似文献
955.
Frankland PW Ding HK Takahashi E Suzuki A Kida S Silva AJ 《Learning & memory (Cold Spring Harbor, N.Y.)》2006,13(4):451-457
Following initial encoding, memories undergo a prolonged period of reorganization. While such reorganization may occur in many different memory systems, its purpose is not clear. Previously, we have shown that recall of recent contextual fear memories engages the dorsal hippocampus (dHPC). In contrast, recall of remote contextual fear memories engages a number of different cortical regions, including the anterior cingulate cortex (ACC). To examine whether this reorganization leads to greater memory stability, we examined reconsolidation of 1 d-old (recent) and 36 d-old (remote) contextual fear memory in mice. We infused the protein synthesis inhibitor, anisomycin (ANI), into either the dHPC or ACC immediately following retrieval of either a recent or remote contextual fear memory. In the dHPC, ANI infusions disrupted subsequent expression of recent, but not remote, contextual fear memory. Similar infusions into the ACC had no effect on either recent or remote contextual fear memories, whereas systemically applied ANI blocked subsequent remote memory expression when long re-exposure durations were used. Together, these data suggest that as memories mature they become increasingly stable. Furthermore, the dissociation between the effects of systemically and centrally administered ANI on remote memory suggests that stability is due, in part, to the distributed nature of remote contextual fear memories. 相似文献
956.
While there is evidence that feedback projections from cortical and neuromodulatory structures to the olfactory bulb are crucial for maintaining the oscillatory dynamics of olfactory bulb processing, it is not clear how changes in dynamics are related to odor perception. Using electrical lesions of the olfactory peduncle, sparing output from the olfactory bulb while decreasing feedback inputs to the olfactory bulb, we demonstrate here a role for feedback inputs to the olfactory bulb in the formation of odor-reward associations, but not for maintaining primary bulbar odor representations, as reflected by spontaneous odor discrimination. 相似文献
957.
Hippocampal train stimulation modulates recall of fear extinction independently of prefrontal cortex synaptic plasticity and lesions
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Farinelli M Deschaux O Hugues S Thevenet A Garcia R 《Learning & memory (Cold Spring Harbor, N.Y.)》2006,13(3):329-334
It has been shown that long-term potentiation (LTP) develops in the connection between the mediodorsal thalamus (MD) and the medial prefrontal cortex (mPFC) and between the hippocampus (HPC) and the mPFC following fear extinction, and correlates with extinction retention. However, recent lesion studies have shown that combined lesions of the MD and mPFC do not interfere with extinction learning and retention, while inactivation of the dorsal HPC disrupts fear extinction memory. Here we found in rats that immediate post-training HPC low-frequency stimulation (LFS) suppressed extinction-related LTP in the HPC-mPFC pathway and induced difficulties in extinction recall. HPC tetanus, applied several hours later, failed to re-establish mPFC LTP but facilitated recall of extinction. Delayed post-training HPC LFS also provoked mPFC depotentiation and difficulties with extinction recall. HPC tetanus abolished these two effects. We also found that damage to the mPFC induced fear return only in rats that received HPC LFS following extinction training. HPC tetanus also reversed this behavioral effect of HPC LFS in lesioned rats. These data suggest that the HPC interacts with the mPFC during fear extinction, but can modulate fear extinction independently of this interaction. 相似文献
958.
Kinoshita S 《Psychonomic bulletin & review》2006,13(4):668-673
In previous studies, additive effects of masked repetition and word frequency on lexical decision latency have been reported.
This additive pattern was replicated in Experiment 1 with the use of lowfrequency words (range, 1–7 per million) selected
at random. In contrast, in Experiment 2, in which low-frequency words known to be familiar to the subjects were used, the
masked repetition priming effect was greater for low-frequency than for high-frequency words. It is suggested that the absence
of an interaction between masked repetition and frequency observed in previous studies and in the present Experiment 1 was
due to the fact that very-low-frequency words often have an unstable representation in the subjects’ lexicon and, consequently,
sometimes fail to produce repetition priming effects in full. 相似文献
959.
Our reduced ability to correctly report two sequentially presented targets is seen in the robust effect known as the attentional
blink (AB; Raymond, Shapiro, & Arnell, 1992). One recent report (Olivers & Nieuwenhuis, 2005) strikingly reveals the AB to
be virtually abolished when non-task-demanding music occurs in the background. The authors suggest that a diffuse attentional
state is the mediating factor. Here, we seek to broaden the finding’s generality by determining if task-irrelevant visual
motion and flicker also attenuate the AB. In our experiments, the AB task was presented together with a background field of
moving dots that could moveaway from ortoward the central AB task, or flicker. In the control condition, the dots remained static. The AB was attenuated—though to different
degrees—in all experimental conditions, but not in the static condition. Our findings add to the generality of the previous
conclusions, and we emphasize an account based on the overallocation of attention. 相似文献
960.
Electrolytic lesions of the medial prefrontal cortex do not interfere with long-term memory of extinction of conditioned fear
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Lesion studies indicate that rats without the medial prefrontal cortex (mPFC) have difficulty recalling fear extinction acquired the previous day. Several electrophysiological studies have also supported this observation by demonstrating that extinction-related increases in neuronal activity in the mPFC participate in expression of fear extinction. However, a more recent study has shown that fear extinction can be recalled, in certain circumstances, without mPFC potentiation, suggesting contribution of other circuits. Here, we examined this possibility in rats that were subjected to auditory fear conditioning, extinction training, and extinction retention test 7 d later. Electrolytic lesions were made in the mPFC, the motor cortex (MO), the dorsal septum (SEP), or the mediodorsal thalamus (MD), because of their potential participation in conditioned fear inhibition; combined lesions including the mPFC with the MO, SEP, or MD were also made. The lesions were made either 1 wk before conditioning or 1 d after extinction training. All rats normally extinguished their conditioned freezing behavior during extinction training and did not display any return of this behavior during the retention test. These data reveal that the mPFC is not required for the acquisition, the expression, or the retrieval of extinction memories but do not exclude the possibility that the mPFC normally participates in these processes. 相似文献