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91.
Persons with Down syndrome (DS) suffer from prefrontal cortex dysfunction and deficits in executive functions. The current study examined the effects assisted cycling therapy (ACT) on short-term (STM) and working memory (WM) in adolescents with DS. During ACT, the cadence of participants on a stationary bicycle was augmented with an electrical motor to 180% of the voluntary cadence. Participants completed eight weeks of ACT (n?=?17), eight weeks of voluntary cycling (VC) at their own preferred cadence (n?=?16), or eight weeks of no cycling (np?≥?.149) and working memory improved only in the ACT group (Hedge’s g?=?1.66; p?=?.003). The results indicate that assisted high-cadence cycling (i.e. ACT) produces superior neural benefits in the dorsolateral prefrontal cortex compared to VC.  相似文献   
92.
Presymptomatic identification of disease gene carriers is becoming an increasingly common part of the clinical management of hereditary cancer disorders. With an expected increase in the number of requests for DNA testing and the limited resources for counseling, the amount of time genetic counselors are able to spend with test candidates will decrease. It is therefore important for counselors to identify persons at risk for psychological distress. Based on a review of experiences with Huntington disease and cancer patients, we describe factors likely to evoke distress in genetic cancer candidates. We also discuss the sometimes widely different ways that test candidates and their partners respond to genetic testing. By exploring risk factors for distress in relevant domains of the research, we can offer counselors guidelines for determining who may need extra counseling.  相似文献   
93.
The recent explosion of studies aimed at determining the biological basis of intelligence has revealed that cognitive ability has a strong biological substrate. This study expands on this literature by examining the relation between cognitive ability and MRI-measured brain volume and head size in a sample of adult male siblings recruited from the London, Ontario community in Canada. It was found that brain volume correlated with IQ at 0.35 (P<0.01), thus replicating the results of past studies. Corrections for restriction of range and attenuation in both this and past studies suggest that the population value of the brain volume-IQ correlation is closer to 0.50. Head size variables, with one exception, also showed the expected positive correlations with IQ. The results of a vector analysis on factor scores indicated that the more highly g-loaded a test was the more highly it correlated with brain volume (r=0.59, P<0.01). The sum of the data suggested that although brain volume (and to a lesser extent, head size) is predictive of g, fluid ability, and memory, it does not predict crystallized ability. Unexpectedly, the higher the spatial imaging loading of a test, the less its correlation with brain volume (vector correlation=−0.84, P<0.001).  相似文献   
94.
白细胞介素-6和胎盘生长因子对子痫前期影响的研究   总被引:1,自引:0,他引:1  
为探讨影响子痫前期患者发病的因素,对照性检测了子痫前期患者羊水中白细胞介素-6和胎盘中胎盘生长因子的变化。结果显示:子痫前期患者白细胞介素-6和胎盘生长因子均明显下降,且二者下降水平呈高度正相关。故联合检测白细胞介素-6和胎盘生长因子将对评估子痫前期的病情及指导临床决策具有重要意义。  相似文献   
95.
We studied indirect victimization from an evolutionary perspective by examining links between this type of victimization and several indicators of attractiveness (past sexual behavior, dating frequency and physical appearance). Two thousand three hundred and nineteen (56% female) students (ages 13-18) from a region of southern Ontario, Canada, completed self-report measures of indirect victimization, physical appearance, dating frequency, recent sexual behavior (number of partners in previous month) and past sexual behavior (number of lifetime partners minus number of partners in previous month) as well as indexes of depression, aggression and attachment security, which were used to control for psychosocial maladjustment. Consistent with an evolutionary framework, physical appearance interacted significantly with gender, wherein attractive females were at greater risk for indirect victimization, whereas for males physical attractiveness was a protective factor, reducing risk of victimization. Physical appearance also interacted with grade, being inversely related to indirect victimization for younger adolescents and having a nonsignificant association with victimization for older youth. Finally, recent sexual behavior was associated with increased risk of indirect victimization for older adolescents only, which we discussed with regard to peer perceptions of promiscuity and short-term mating strategies. These findings have important implications for the development of interventions designed to reduce peer victimization, in that victims of indirect aggression may represent a rather broad, heterogeneous group, including attractive individuals with no obvious signs of maladjustment.  相似文献   
96.
Psychosocial factors have been shown to play an important role in the aetiology of coronary heart disease (CHD). A strong association between CHD and socioeconomic status (lower-level education, poor financial situation) has also been well established. Socioeconomic differences may thus also have an effect on psychosocial risk factors associated with CHD, and socioeconomic disadvantage may negatively affect the later prognosis and quality of life of cardiac patients. The aim of this study was to review the available evidence on socioeconomic differences in psychosocial factors which specifically contribute to CHD. A computer-aided search of the Medline and PsycINFO databases resulted in 301 articles in English published between 1994 and 2007. A comprehensive screening process identified 12 empirical studies which described the socioeconomic differences in CHD risk factors. A review of these studies showed that socioeconomic status (educational grade, occupation or income) was adversely associated with psychosocial factors linked to CHD. This association was evident in the case of hostility and depression. Available studies also showed a similar trend with respect to social support, perception of health and lack of optimism. Less consistent were the results related to anger and perceived stress levels. Socioeconomic disadvantage seems to be an important element influencing the psychosocial factors related to CHD, thus, a more comprehensive clarification of associations between these factors might be useful. More studies are needed, focused not only on well-known risk factors such as depression and hostility, but also on some lesser known psychosocial factors such as Type D and vital exhaustion and their role in CHD.  相似文献   
97.
This longitudinal study was conducted among 102 women with non-metastasic breast cancer to identify the time evolution and prevalence of distress at specific times through diagnosis and treatment of disease: preliminary diagnosis, surgery, definitive diagnosis and chemotherapy. Additionally, the study aimed to examine the role of demographic, medical and psychosocial factors on distress. The results indicated that prevalence of distress was higher at initial diagnosis (25%) than the following time points (approximately 17%). The differences inter-individuals in the levels of distress were observed over the four assessments. No relation between distress and demographic and medical factors was found. However, psychosocial aspects were significant risk factors. Patterns of emotional suppression and specific coping responses like helplessness/hopelessness, anxious preoccupation, cognitive avoidance and fatalism were positively related to distress, whereas fighting spirit and perceived social support showed a protective role. Moreover, helplessness/hopelessness and anxious preoccupation jointly predicted 75% of cases and 98% non-cases of distress. Finally, a mediational model between emotional suppression and distress through helplessness/hopelessness was tested. Results support the necessity of routine distress screening all through the illness. Implications of data for psychosocial interventions with breast cancer patients are highlighted.  相似文献   
98.
The driver of a conditionally automated vehicle equivalent to level 3 of the SAE is obligated to accept a takeover request (TOR) issued by the vehicle. Considerable research has been conducted on the TOR, especially in terms of the effectiveness of multimodal methods. Therefore, in this study, the effectiveness of various multimodalities was compared and analyzed. Thirty-six volunteers were recruited to compare the effects of the multimodalities, and vehicle and physiological data were obtained using a driving simulator. Eight combinations of TOR warnings, including those implemented through LED lights on the A-pillar, earcon, speech message, or vibrations in the back support and seat pan, were analyzed to clarify the corresponding effects. When the LED lights were implemented on the A-pillar, the driver reaction was faster (p = 0.022) and steering deviation was larger (p = 0.024) than those in the case in which no LED lights were implemented. The speech message resulted in a larger steering deviation than that in the case of the earcon (p = 0.044). When vibrations were provided through the haptic seat, the reaction time (p < 0.001) was faster, and the steering deviation (p = 0.001) was larger in the presence of vibrations in the haptic seat than no vibration. An interaction effect was noted between the visual and auditory modalities; notably, the earcon resulted in a small steering deviation and skin conductance response amplitude (SCR amplitude) when implemented with LED lights on the A-pillar, whereas the speech message led to a small steering deviation and SCR amplitude without the LED lights. In the design of a multimodal warning to be used to issue a TOR, the effects of each individual modality and corresponding interaction effects must be considered. These effects must be evaluated through application to various takeover situations.  相似文献   
99.
IntroductionThe continued progression of the digital age raises the question of Internet and social media abuse among adolescents and of the need for more specific assessment instruments to measure the phenomenon.ObjectiveThe purpose of the current study was to explore the role of intrapersonal and interpersonal factors influencing Internet addiction, as well as to evaluate the psychometric properties of the Internet Related Experiences Questionnaire (IREQ-I) in relation to a sample of Italian adolescents.MethodTwo studies were designed. In study 1, a school-based sample of 838 Italian adolescents was recruited to test the psychometric properties of the IREQ-I by using a robust Confirmatory Factor Analysis (CFA). In study 2, a total of 438 Italian adolescents were recruited to investigate the concurrent validity of the instrument.ResultsWe found that intrapersonal rather than interpersonal factors were associated with Internet abuse. The final version of the IREQ-I showed a good level of fit and the bi-factorial solution was consistent with the previous findings.ConclusionThe results of this study suggest that the IREQ-I is a valuable bifactorial instrument for measuring Internet abuse, including both intrapersonal and interpersonal factors as theoretically relevant constructs.  相似文献   
100.
Determinate solutions for the indeterminate common factor ofp variables satisfying the single common factor model are not unique. Therefore an infinite sequence of additional variables that conform jointly with the originalp variables to the original single common factor model does not determine a unique solution for the indeterminate factor of thep variables (although the solution is unique for the factor of the infinite sequence). Other infinite sequences may be found to determine different solutions for the factor of the originalp variables. The paper discusses a number of theorems about the effects of additional variables on factor indeterminacy in a model with a single common factor and draws conclusions from them for factor theory in general.  相似文献   
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