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841.
842.
Falcone DC Wood EM Xie SX Siderowf A Van Deerlin VM 《Journal of genetic counseling》2011,20(4):384-395
The most common genetic contributor to late-onset Parkinson disease (PD) is the LRRK2 gene. In order to effectively integrate LRRK2 genetic testing into clinical practice, a strategy tailored to the PD population must be developed. We assessed 168 individuals
with PD for baseline knowledge of genetics, perceived risk, and interest and opinions regarding genetic counseling and testing.
Most participants felt that they were familiar with general genetics terms but overall knowledge levels were low, with an
average score of 55%. The majority of participants thought it was likely they inherited a PD gene (72%), believed genetic
testing for PD would be useful (86%), and were interested in genetic testing (59%) and genetic counseling (56%). However,
only a few participants had heard of any genetic tests for PD (29%) or LRRK2 (10%). There appears to be a significant level of interest in genetics and genetic testing within the PD population, but
a considerable deficit in genetics knowledge and an over-estimation of risk. Genetic education and counseling tools to address
these needs were developed to provide patients with the ability to make informed and knowledgeable genetic testing decisions. 相似文献
843.
Receiver operating characteristics (ROCs) have been used extensively to study the processes underlying human recognition memory, and this method has recently been applied in studies of rats. However, the extent to which the results from human and animal studies converge is neither entirely clear, nor is it known how the different methods used to obtain ROCs in different species impact the results. A recent study used a response bias ROC manipulation with rats and demonstrated that speeding memory responses reduced the contribution of recollection, not familiarity. The current study confirms this finding in humans using a comparable response bias method. Moreover, a comparison of the response bias methods commonly used in animal studies and the confidence rating method typically employed in human studies produced similar ROC functions. The present results suggest that the analysis of recognition memory ROCs provides a fruitful method to bridge the human and animal memory literatures. 相似文献
844.
This article uses a general latent variable framework to study a series of models for nonignorable missingness due to dropout. Nonignorable missing data modeling acknowledges that missingness may depend not only on covariates and observed outcomes at previous time points as with the standard missing at random assumption, but also on latent variables such as values that would have been observed (missing outcomes), developmental trends (growth factors), and qualitatively different types of development (latent trajectory classes). These alternative predictors of missing data can be explored in a general latent variable framework with the Mplus program. A flexible new model uses an extended pattern-mixture approach where missingness is a function of latent dropout classes in combination with growth mixture modeling. A new selection model not only allows an influence of the outcomes on missingness but allows this influence to vary across classes. Model selection is discussed. The missing data models are applied to longitudinal data from the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study, the largest antidepressant clinical trial in the United States to date. Despite the importance of this trial, STAR*D growth model analyses using nonignorable missing data techniques have not been explored until now. The STAR*D data are shown to feature distinct trajectory classes, including a low class corresponding to substantial improvement in depression, a minority class with a U-shaped curve corresponding to transient improvement, and a high class corresponding to no improvement. The analyses provide a new way to assess drug efficiency in the presence of dropout. 相似文献
845.
Using a quantitative–qualitative mixed design, the current study investigated relationship violence within 35 gay male couples
living in Santiago, Cuba. Informants narrated how violence was enacted within their relationship. Qualitative analyses revealed
men’s construction of masculinity and the sequelae of economic hardships—which led to economic emasculinization—were primary
contributors to relationship abuse. Gendered interpretations to the display of heightened masculinity contributed to intimate
partner violence. Enacted interpersonal violence was not meaningfully associated with alcohol consumption or to personality
measures. We suggest the economic constraints that are perceived by couples to precipitate relational stress may be similar
across heterosexual and gay/lesbian couples, and that the relational power accorded to economic privilege cannot be aligned
fully by gender. 相似文献
846.
Neurogenesis continues to occur throughout life in the dentate gyrus of the hippocampus and may be related to hippocampus-dependent learning. We have recently reported that there is an enhancement of neurogenesis in the hippocampus only when BrdU is administered 6 days prior to starting spatial training but not when training started either 1 day or 11 days following BrdU administration. In that study, all rats were perfused on day 16 after BrdU injection in order to compare cells of the same age (i.e. 16 day old cells) and thus the survival time after learning was different between groups. This study was designed to address whether the amount of time that passed following training could also contribute to the effects of spatial learning on hippocampal neurogenesis and whether there was differential new neuron activation in response to spatial learning that depended on the age of new cells at the time of spatial learning. Here we tested whether a survival period of 5 days following spatial learning at either 1-5, 6-10 or 11-15 days following BrdU administration would alter cell survival and/or activation of new neurons. Our results indicate that 5 days after training in the Morris water task cell survival is unaltered by training on days 1-5, increased by training at days 6-10 and decreased when training occurs on days 11-15. Furthermore spatial learners trained on days 6-10 or 11-15 show greater activation of new neurons compared to cue-trained rats during a probe trial 5 days after training. In addition, rats trained on the spatial task on days 11-15 had a greater number of activated new neurons compared to rats trained on the spatial task on days 6-10. These results suggest there is a gradual removal of older BrdU-labeled new neurons following spatial learning perhaps due to a competitive interaction with a population of younger BrdU-labeled new neurons. 相似文献
847.
Trogrlic L Wilson YM Newman AG Murphy M 《Learning & memory (Cold Spring Harbor, N.Y.)》2011,18(10):678-687
The identity and distribution of neurons that are involved in any learning or memory event is not known. In previous studies, we identified a discrete population of neurons in the lateral amygdala that show learning-specific activation of a c-fos-regulated transgene following context fear conditioning. Here, we have extended these studies to look throughout the amygdala for learning-specific activation. We identified two further neuronal populations, in the amygdalo-striatal transition area and medial amygdala, that show learning-specific activation. We also identified a population of hypothalamic neurons that show strong learning-specific activation. In addition, we asked whether these neurons are activated following recall of fear-conditioning memory. None of the populations of neurons we identified showed significant memory-recall-related activation. These findings suggest that a series of discrete populations of neurons are involved in fear learning in amygdala and hypothalamus. The lack of reactivation during memory recall suggests that these neurons either do not undergo substantial change following recall, or that c-fos is not involved in any such activation and change. 相似文献
848.
849.
Basen-Engquist K Carmack CL Perkins H Hughes D Serice S Scruggs S Pinto B Waters A 《Psychology of sport and exercise》2011,12(1):27-35
Physical activity has been shown to benefit cancer survivors' physical functioning, emotional well-being, and symptoms. Physical activity may be of particular benefit to survivors of endometrial cancer because they are more likely to be obese and sedentary than the general population, as these are risk factors for the disease, and thus experience a number of related co-morbid health problems. However, there is little research systematically studying mechanisms of physical activity adherence in cancer survivor populations. This paper describes the design of the Steps to Health study, which applies a Social Cognitive Theory-based model of endometrial cancer survivors' adoption and maintenance of exercise in the context of an intervention to increase walking or other moderate intensity cardiovascular activity. In Steps to Health we will test the influence of self-efficacy and outcome expectations on adherence to exercise recommendations, as well as studying the determinants of self-efficacy. Endometrial cancer survivors who are at least 6 months post-treatment are provided with an intervention involving print materials and telephone counseling, and complete assessments of fitness, activity, self-efficacy and outcome expectations, and determinants of self-efficacy every two months for a six month period. In addition to testing an innovative model, the Steps to Health study employs multiple assessment methods, including ecological momentary assessment, implicit tests of cognitive variables, and ambulatory monitoring of physical activity. The study results can be used to develop more effective interventions for increasing physical activity in sedentary cancer survivors by taking into account the full complement of sources of self-efficacy information and outcome expectations. 相似文献
850.