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151.
Rodrigues CS de Oliveira VZ Camargo G Osório CM de Castilhos RM Saraiva-Pereira ML Schuler-Faccini L Jardim LB 《Journal of genetic counseling》2012,21(1):101-112
Diagnostic tests are available to detect several mutations related to adult-onset, autosomal dominant, neurodegenerative diseases.
We aimed to describe our experience in a presymptomatic testing program run by the Brazilian Public Health System from 1999
to 2009. A total of 184 individuals were eligible for presymptomatic testing due to a risk for spinocerebellar ataxia (SCA)
- SCA3 (80%), Huntington’s disease (11.9%), familial amyloidotic neuropathy (4.3%), SCA1, SCA2, SCA6, or SCA7. Most were women
(70%), married (54%), and had children prior to presymptomatic testing (67%). Their mean age at entrance was 34 (SD = 11 years).
Educational level was above the average Brazilian standard. After receipt of genetic counseling, 100 individuals (54%) decided
to undergo testing; of these, 51 were carriers. Since no individual returned for post-test psychological evaluation, we conducted
a subsequent survey, unrelated to test disclosures. We contacted 57 individuals of whom 31 agreed to participate (24 had been
tested, 7 had not). Several ascertainment concerns relating to these numerous losses prevented us from generalizing our results
from this second survey. We concluded that: decision-making regarding presymptomatic testing seems to be genuinely autonomous,
since after genetic counseling half the individuals who asked for presymptomatic testing decided in favor and half decided
against it; general characteristics of Brazilians who sought presymptomatic testing were similar to many European samples
studied previously; and individuals at risk for SCA3 may be at greater risk of depression. Although no clear-cut reason emerged
for rejection of follow-up psychological sessions after presymptomatic testing, this finding suggests adjustments to our presymptomatic
testing program are necessary. 相似文献
152.
Tellez R Gómez-Viquez L Liy-Salmeron G Meneses A 《Neurobiology of learning and memory》2012,98(1):66-77
Notwithstanding several neurotransmission systems are frequently related to memory formation; forgetting process and neurotransmission systems or their transporters; the role of γ-aminobutyric acid (GAT1), glutamate (EACC1), dopamine (DAT) and serotonin (SERT) is poorly understood. Hence, in this paper western-blot analysis was used to evaluate expression of GAT1, EAAC1, DAT and SERT during forgetting in trained and untrained rats treated with the selective serotonin transporter inhibitor fluoxetine, the amnesic drug d-methamphetamine (METH) and fluoxetine plus METH. Transporters expression was determined in the hippocampus (HIP), prefrontal cortex (PFC) and striatum (STR). Results indicated that forgetting of Pavlovian/instrumental autoshaping was associated to up-regulation of GAT1 (PFC and HIP) and DAT (PFC) while SERT (HIP) was down-regulated; no-changes were observed in striatum. Methamphetamine administration did not affect forgetting at 216 h post-training but up-regulated hippocampal DAT and EACC, prefrontal cortex DAT and striatal GAT1 or EACC1. Fluoxetine alone prevented forgetting, which was associated to striatal GAT1 and hippocampal DAT up-regulation, but prefrontal cortex GAT1 down-regulation. Fluoxetine plus METH administration was also able to prevent forgetting, which was associated to hippocampal DAT, prefrontal cortex SERT and striatal GAT1, DAT or SERT up-regulation, but prefrontal cortex GAT1 down-regulation. Together these data show that forgetting provokes primarily hippocampal and prefrontal cortex transporters changes; forgetting represent a behavioral process hardly modifiable and its prevention could causes different transporters expression patterns. 相似文献
153.
Bayesian structural equation modeling: A more flexible representation of substantive theory 总被引:1,自引:0,他引:1
This article proposes a new approach to factor analysis and structural equation modeling using Bayesian analysis. The new approach replaces parameter specifications of exact zeros with approximate zeros based on informative, small-variance priors. It is argued that this produces an analysis that better reflects substantive theories. The proposed Bayesian approach is particularly beneficial in applications where parameters are added to a conventional model such that a nonidentified model is obtained if maximum-likelihood estimation is applied. This approach is useful for measurement aspects of latent variable modeling, such as with confirmatory factor analysis, and the measurement part of structural equation modeling. Two application areas are studied, cross-loadings and residual correlations in confirmatory factor analysis. An example using a full structural equation model is also presented, showing an efficient way to find model misspecification. The approach encompasses 3 elements: model testing using posterior predictive checking, model estimation, and model modification. Monte Carlo simulations and real data are analyzed using Mplus. The real-data analyses use data from Holzinger and Swineford's (1939) classic mental abilities study, Big Five personality factor data from a British survey, and science achievement data from the National Educational Longitudinal Study of 1988. (PsycINFO Database Record (c) 2012 APA, all rights reserved). 相似文献
154.
This rejoinder discusses the general comments on how to use Bayesian structural equation modeling (BSEM) wisely and how to get more people better trained in using Bayesian methods. Responses to specific comments cover how to handle sign switching, nonconvergence and nonidentification, and prior choices in latent variable models. Two new applications are included. The first one revisits the Kaplan (2009) science model by considering priors on primary parameters. The second one applies BSEM to the bifactor model that was hypothesized in the original Holzinger and Swineford (1939) study. (PsycINFO Database Record (c) 2012 APA, all rights reserved). 相似文献
155.
Meilán JJ Martínez-Sánchez F Carro J Sánchez JA Pérez E 《The Spanish journal of psychology》2012,15(2):487-494
This study broaches in a novel way the analysis of cognitive impairment characteristic of the early stages of Alzheimer's Disease (AD). Specifically, we attempt to determine the acoustic speech parameters that are sensitive to the onset of the disease, and their association with the language deficit characteristic of AD. Speech analysis was carried out on 21 elderly patients with AD using Praat software, which analyzes the acoustic components of speech. The data obtained were subjected to stepwise regression, using the overall scores obtained in the test as the criterion variable, and the scores on the frequency, amplitude and periodicity variables as predictors of performance. We found that the percentage of voiceless segments explains a significant portion of the variance in the overall scores obtained in the neuropsychological test. This component seems to be related mainly to the patient's ability in phonological fluency. This finding could permit the creation of a diagnostic test for AD through analysis of the acoustic speech parameters at very low cost in terms of both time and resources. 相似文献
156.
The aim of this study is to fill a gap in intelligence research by presenting data for the average IQ in Morocco and for a comparable sample in Spain. Adult samples were administered the Raven Standard Progressive Matrices (SPM) (Raven, Court, & Raven, 2001) and scored for the total test and for the three sub-factors of gestalt continuation, verbal-analytical reasoning and visuospatial ability identified by Lynn, Allik, and Irwing (2004). The total test and the three factors have shown satisfactory reliability. Our results for the Moroccan sample show significant relationship between general intelligence factor, gestalt continuation and visuospatial ability with education level and income. Conversely, these variables have been shown to be independent for the Spanish sample. This sample obtained significantly higher scores for the four factors assessed than the Moroccan one. These differences have been found also comparing samples with the same education levels. Finally, the errors percentage for Moroccans has been higher than for Spaniards in all the items, suggesting that the level of difficulty was higher for the Moroccan sample. 相似文献
157.
The purpose of this study was to investigate the moderating effect of having vs. not having a and quality of life. In-person interviews were conducted with 55 male and 64 female inmates from the Topas Penitentiary (Spain). Higher levels of social loneliness and lower levels of sexual satisfaction were associated with lower levels of quality of life. In addition, the interaction between sexual satisfaction and romantic partner status was significant. Higher levels of sexual satisfaction were associated with higher levels of quality of life only for the group without a partner. These findings support a "bad is stronger than good" principle and indicate the detrimental aspects that can be associated with not having a satisfactory sexual life while incarcerated. 相似文献
158.
As a result of studies examining factors involved in the learning process, various structural models have been developed to explain the direct and indirect effects that occur between the variables in these models. The objective was to evaluate a structural model of cognitive and motivational variables predicting academic achievement, including general intelligence, academic self-concept, goal orientations, effort and learning strategies. The sample comprised of 341 Spanish students in the first year of compulsory secondary education. Different tests and questionnaires were used to evaluate each variable, and Structural Equation Modelling (SEM) was applied to contrast the relationships of the initial model. The model proposed had a satisfactory fit, and all the hypothesised relationships were significant. General intelligence was the variable most able to explain academic achievement. Also important was the direct influence of academic self-concept on achievement, goal orientations and effort, as well as the mediating ability of effort and learning strategies between academic goals and final achievement. 相似文献
159.
Cantón Duarte J Cortés Arboleda MR Cantón-Cortés D 《The Spanish journal of psychology》2012,15(2):571-581
This study analyzes the prevalence and characteristics of childhood and adolescence sexual abuse suffered by a sample of university students, as well as the variables associated with the nature of abuse. Participants anonymously completed the Questionnaire on Child Sexual Abuse, in order to obtain information about experience of sexual abuse. Of a total of 2,375 students, 289 (12.2%) declared having suffered sexual abuse before the age of 18. The invasiveness, continuity, and severity of abuse was related to the location where the abuse took place (the more severe cases were committed in the homes of the victim and perpetrator) and to the circumstances of abuse (relationships with partners/at a party or while caring for a child predicted more severe abuse). The age of the victim (preschool) and an intrafamilial relationship between victim and perpetrator were also related to more invasive, continuous, and severe sexual abuse. The knowledge of characteristics of perpetrator and victim and the context in which sexual abuse occurs can help to better comprehend the nature and correlates of sexual abuse. The results of the present study may contribute to the design of programs for the prevention of sexual abuse to minors. 相似文献
160.
This study involved 219 women participants. The main aim of the present study is to examine the perceived consequences of a work-related promotion for the female partner in a heterosexual relationship. The impact of the promotion was manipulated - both partners share paid and domestic work, the male partner taking responsibility for all the domestic work - or female partner continuing to do all the domestic work, as well as the male partner's sexist ideology. Finally, the study examined gender ideology of participants. The results showed that participants felt that violence was more likely when the male partner was presented as sexist and that this was due to a perception of threat on the part of the male partner. 相似文献