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991.
A simple method was designed to evaluate visual abilities such as disance visual acuity, binocular horizontal visual field, simple and choice visual reaction times, and stereoscopic vision in skilled 11- to 13-yr.-old basketball players participating in a 15-day summer training camp. On a test battery, visual abilities were monitored in 473 players of the Spanish Basketball Federation over a 5-yr. period. The players showed outstanding scores on distance visual acuity and stereoscopic vision, and good visual reaction times and horizontal visual fields. When scores were compared by sex and age, significant differences on certain visual measures were observed. Many layers showed crossed eye-hand dominance. Visual screening programs may help promote visual health among junior basketball players and could be used for performance training.  相似文献   
992.
A long-standing debate on assessment has troubled research on field dependence-independence. The main arguments and a recent measurement proposal by Riding, et al., are revised to illustrate the futility of this debate and to defend the strength of the cognitive style dimension.  相似文献   
993.
This study examined the effect of different types of feedback on goal orientation, perception of motivational climate, satisfaction, and boredom in physical education (PE) classes, pupils' preferences for challenging versus easy tasks, pupils' attitudes towards PE lessons, and perception of gymnastic ability. 95 subjects in three treatment conditions (positive feedback, negative feedback, and both feedback types) participated in 14 lessons and completed pre- and postintervention measures. Results showed that subjects in the positive feedback group had significantly higher scores on learning-oriented motivational climate and enjoyment than the subjects of the negative feedback group. The negative feedback group reported higher scores on performance-oriented motivational climate than the positive feedback group. Results also showed that subjects in the group receiving both types of feedback had lower scores on learning-oriented motivational climate, higher scores on enjoyment than the negative feedback group, and lower scores on boredom than the positive feedback group. The effects of feedback on physical education students' motivation are discussed.  相似文献   
994.
995.
This study deals with decision and execution behavior of tennis players during competition. The study is based on the expert-novice paradigm and aims to identify differences between both groups in the decision-making and execution variables in serve and shot actions in tennis. Six expert players (elite Spanish tennis players) and six novice players (grade school tennis players) took part in this study. To carry out this study, the observation protocol defined by McPherson and Thomas in 1989, in which control, decision-making and execution variables were included, was used, where it was applied to the performance of the tennis player in a real match situation. In the analysis, significant differences between experts and novices in decision-making and execution variables are found wherein it can be observed that experts display a greater ability to make the appropriate decisions, selecting the most tactical responses to put pressure on the opponent. Expert tennis players were also able to carry out forceful executions to their opponent with greater efficiency, making the opponent's response to a large extent more difficult. These findings are in accordance with those of McPherson and colleagues.  相似文献   
996.
Executive functions include abilities of goal formation, planning, carrying out goal-directed plans, and effective performance. This article aims at reviewing some of the current knowledge surrounding executive functioning and presenting the contrasting views regarding this concept. The neural substrates of the executive system are examined as well as the evolution of executive functioning, from development to decline. There is clear evidence of the vulnerability of executive functions to the effects of age over lifespan. The first executive function to emerge in children is the ability to inhibit overlearned behavior and the last to appear is verbal fluency. Inhibition of irrelevant information seems to decline earlier than set shifting and verbal fluency during senescence. The sequential progression and decline of these functions has been paralleled with the anatomical changes of the frontal lobe and its connections with other brain areas. Generalization of the results presented here are limited due to methodological differences across studies. Analysis of these differences is presented and suggestions for future research are offered.  相似文献   
997.
Hereditary breast cancer (HBC) accounts for 5–10% of breast cancer cases and it significantly increases the lifetime risk of cancer. Our objective was to evaluate the sociodemographic variables, family history of cancer, breast cancer (BC) screening practices and the risk profile of cancer affected or asymptomatic at-risk women that undergo genetic counseling for hereditary breast cancer in public Brazilian cancer genetics services. Estimated lifetime risk of BC was calculated for asymptomatic women using the Gail and Claus models. The majority of women showed a moderate lifetime risk of developing BC, with an average risk of 19.7% and 19.9% by the Gail and Claus models, respectively. The average prior probability of carrying a BRCA1/2 gene mutation was 16.7% and overall only 32% fulfilled criteria for a hereditary breast cancer syndrome as assessed by family history. We conclude that a significant number of individuals at high-risk for HBC syndromes may not have access to the benefits of cancer genetic counseling in these centers. Contributing factors may include insufficient training of healthcare professionals, disinformation of cancer patients; difficult access to genetic testing and/or resistance in seeking such services. The identification and understanding of these barriers is essential to develop specific strategies to effectively achieve cancer risk reduction in this and other countries were clinical cancer genetics is not yet fully established.  相似文献   
998.
We reviewed the Spanish translation of the Youth Quality of Life Instrument-Research Version (YQOL-R) and culturally adapted the measure with Puerto Rican and Mexican American children and adolescents. The YQOL-R is a self-reported measure that includes four domains: Sense of Self, Social Relationships, Environment, and General Quality of Life. A total of 10 focus groups were conducted with children aged 9 to 11, adolescents aged 12 to 17, their parents, and mental health providers. Five focus groups were conducted in San Diego, California and five in San Juan, Puerto Rico. Eligible participants were recruited from children’s outpatient psychiatry clinics. We followed an iterative and recursive process in reviewing changes and modifications to the instrument using a bilingual committee and a Multi National Bilingual Committee. Greater semantic, content, and technical equivalence of the Spanish and English versions for the YQOL-R was achieved for the two largest U.S. Latino subgroups: Mexican Americans and Puerto Ricans. The cultural adaptation process revealed several important issues regarding the measurement of quality of life in different age groups. Additional items for school, relationships (both family and friends) and spare time suggested the need for a future children’s version of the instrument. For the adolescents, additional items were suggested in the areas of sexuality, intergenerational conflict and acculturative stress.  相似文献   
999.
The goal of this study was to develop a simple, easy, and quick self-report measure, the Lupus Symptom Inventory (LSI), designed to evaluate subjective symptoms of Systemic Lupus Erythematosus (SLE). The internal consistency of the LSI was tested, as well as its concordance with physician reports and serological indicators of disease activity by evaluating the self-reports of 46 patients with SLE who completed the LSI daily for a one-month period. Throughout this one-month period, parameters of serological activity and routine medical check-up were obtained. The results showed a high internal consistency of the LSI, with a Cronbach alpha of .86. Additionally, a contingency analysis showed agreement between medical report and patient self-report on the same day for six of seven lupus symptoms (difficulty breathing (p < .004), joint pain (p < .001), loss of appetite (p < .003), general malaise (p < .005), fatigue (p < .005), and skin rash (p < .018)) but not for abdominal symptoms. Finally, differences were found between LSI scores of patients with high versus low serological activity (χ2(1) = 5.302; p < .021), with the former presenting higher LSI scores than the latter. These results show that the LSI may be a reliable and valid instrument for evaluating the subjective symptoms of the disease as well as its fluctuations.  相似文献   
1000.
Reconsolidation of declarative memory in humans   总被引:1,自引:0,他引:1       下载免费PDF全文
The reconsolidation hypothesis states that a consolidated memory could again become unstable and susceptible to facilitation or impairment for a discrete period of time after a reminder presentation. The phenomenon has been demonstrated in very diverse species and types of memory, including the human procedural memory of a motor skill task but not the human declarative one. Here we provide evidence for both consolidation and reconsolidation in a paired-associate learning (i.e., learning an association between a cue syllable and the respective response syllable). Subjects were given two training sessions with a 24-h interval on distinct verbal material, and afterward, they received at testing two successive retrievals corresponding to the first and second learning, respectively. Two main results are noted. First, the first acquired memory was impaired when a reminder was presented 5 min before the second training (reconsolidation), and also when the second training was given 5 min instead of 24 h after the first one (consolidation). Second, the first retrieval proved to influence negatively on the later one (the retrieval-induced forgetting [RIF] effect), and we used the absence of this RIF effect as a very indicator of the target memory impairment. We consider the demonstration of reconsolidation in human declarative memory as backing the universality of this phenomenon and having potential clinical relevance. On the other hand, we discuss the possibility of using the human declarative memory as a model to address several key topics of the reconsolidation hypothesis.  相似文献   
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