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171.
Expansion of newborn screening (NBS) has been driven primarily by a combination of advances in technology and medical treatment, and the sustained advocacy efforts of consumers and voluntary health organizations. The longstanding leadership of the March of Dimes has been credited by many as a critical factor in the expansion and improvement of state NBS programs. From the historic vantage point of four decades of March of Dimes involvement with newborn screening, this report reviews the unique origin of the first newborn screening test, and identifies from this point of origin several of the elements which still define the evolution of advocacy for NBS today. It also documents activities at the federal level and in seven states that have lead to expanded screening for newborns. Advances in NBS technology and medical treatment have informed policy development. Mobilization of volunteers and focused advocacy activities have brought about expansion of screening opportunities for newborns across the United States. But more work is needed. Continued application of the effective strategies identified in this report will help assure that all families have the best possible chance of assuring that their newborns do not have to suffer the complications of conditions that we know can be treated effectively.  相似文献   
172.
This study examined the relation between the amount of mathematical input in the speech of preschool or day-care teachers and the growth of children's conventional mathematical knowledge over the school year. Three main findings emerged. First, there were marked individual differences in children's conventional mathematical knowledge by 4 years of age that were associated with socioeconomic status. Second, there were dramatic differences in the amount of math-related talk teachers provided. Third, and most important, the amount of teachers' math-related talk was significantly related to the growth of preschoolers' conventional mathematical knowledge over the school year but was unrelated to their math knowledge at the start of the school year.  相似文献   
173.
Attachment and motivational strategies in adolescence: exploring links   总被引:2,自引:0,他引:2  
Soares I  Lemos MS  Almeida C 《Adolescence》2005,40(157):129-154
Within the framework of attachment theory and of motivation goal theory, this study explored the relation between quality of attachment strategies and quality of motivational strategies in a sample of young adolescents. Specifically, this study examined patterns of thoughts, behaviors, and emotions as they related to representations of attachment and motivational functioning in situations that challenge or threaten three psychological needs (emotional security, competence, and autonomy). Forty-four students, aged 11 to 14 years, responded to imagined stressful situations in order to: (a) assess attachment strategies; (b) identify and assess students' motivational strategies in stressful classroom circumstances; (c) assess motivational strategies of students with high and low control and agency beliefs; and (d) examine the relations between attachment and motivational strategies. Four distinct action patterns were identified: flexible action, rigid action, passive behavior, and disorganized behavior. Significant relations were found between control beliefs and motivational strategies, as well as a trend toward relations between attachment and motivational strategies, suggesting that secure adolescents show more constructive motivational strategies and less disorganized strategies when compared to insecure adolescents.  相似文献   
174.
OBJECTIVE: Several studies have identified that adjuvant chemotherapy for breast cancer is associated with cognitive impairment; however, the magnitude of this impairment is unclear. This study assessed the severity and nature of cognitive impairment associated with adjuvant chemotherapy by conducting a meta-analysis of the published literature to date. METHOD: Six studies (five cross-sectional and one prospective) meeting the inclusion criteria provided a total of 208 breast cancer patients who had undergone adjuvant chemotherapy, 122 control participants and 122 effect sizes (Cohen's d) falling into six cognitive domains. First, the mean of all the effect sizes within each cognitive domain was calculated (separately for cross-sectional and prospective studies); second, a mean effect size was calculated for all of the effect sizes in each cross-sectional study; and third, regression analyses were conducted to determine any relationships between effect size for each study and four different variables. RESULTS: For the cross-sectional studies, each of the cognitive domains assessed (besides attention) showed small to moderate effect sizes (-0.18 to -0.51). The effect sizes for each study were small to moderate (-0.07 to -0.50) and regression analysis detected a significant negative logarithmic relationship (R2 = .63) between study effect size and the time since last receiving chemotherapy. For the prospective study, effect sizes ranged from small to large (0.11-1.09) and indicated improvements in cognitive function from the beginning of chemotherapy treatment to 3 weeks and even 1 year following treatment. CONCLUSION: This meta-analysis suggests that cognitive impairment occurs reliably in women who have undergone adjuvant chemotherapy for breast cancer but that the magnitude of this impairment depends on the type of design that was used (i.e., cross-sectional or prospective). Thus, more prospective studies are required before definite conclusions about the effects of adjuvant chemotherapy on cognition can be made.  相似文献   
175.
Parkinson's disease is predominantly a dopamine deficiency syndrome, which is produced in the brain by the loss of cells located in a small area in the ventral midbrain called the substantia nigra. Complete unilateral dopamine lesions, based on the administration of toxic substances (ie, 6-hydroxy-dopamine in rats and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine in mice and primates) have been extremely useful in testing strategies of replacement. For example, the functional and biochemical impact of the transplanted ventral mesencephalic dopaminergic progenitors has been characterized to a large extent, using the complete lesion model in rats. Over the last decade, however, studies addressing the ability of neurotrophic factors to protect injured dopamine cells prompted researchers to make available partial and progressive lesion models to allow a window of opportunity to interfere the disease progression. Recent findings relating alpha-synuclein with Parkinson's disease pathology have opened new possibilities to develop alternative models based on the overexpression of this protein using recombinant adeno-associated viral vectors, which is valuable not only for helping to better understand its involvement in the disease process, but also to more closely resemble the neurodegeneration found in Parkinson's disease.  相似文献   
176.
Many behaviors are performed automatically in response to contextual cues rather than conscious intentions, which can make behavior change challenging. The combined discontinuity and self-activation hypotheses predict that disruption to a context that cues behaviors can provide opportunity for behavior change guided by intentions rather than contextual cues. In this study, we asked an online sample of participants (N = 452) to report on desired change in the frequency of new, unwanted, or potentially habitual behaviors following a contextual disruption due to the COVID-19 pandemic. We find a distinction between new ‘start’ behaviors and unwanted ‘stop’ behaviors where new behaviors appear more personally meaningful (i.e. higher in autonomous motivation and positive affective attitude) than unwanted or potentially habitual behaviors. Our results suggest that behavior change theory and interventions that acknowledge differential processes between starting new behaviors and stopping old unwanted behaviors would provide greater insights for behavior science.  相似文献   
177.
178.
This paper presents two studies, conducted in two different countries, investigating perceptions of ingroups as enduring, temporally persistent entities, and introduces a new instrument measuring ‘perceived collective continuity’ (PCC). In Study 1 we show that perceptions of ingroup continuity are based on two main dimensions: perceived cultural continuity (perceived continuity of norms and traditions) and perceived historical continuity (perceived interconnection between different historical ages and events). This study also allows the construction of an internally consistent PCC scale including two subscales tapping on these two dimensions. Study 2 replicates findings from the first study; it also reveals that PCC is positively correlated to a set of social identity-related measures (e.g., group identification and collective self-esteem), and that its effects on these measures are mediated by perceived group entitativity. Overall, these two studies confirm that PCC is an important theoretical construct, and that the PCC scale may become an important instrument in future research on group processes and social identity. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
179.
Identifying the point at which individuals become at risk for academic failure (grade point average [GPA] < 2.0) involves an understanding of which and how many factors contribute to poor outcomes. School-related factors appear to be among the many factors that significantly impact academic success or failure. This study focused on 12 school-related factors. Using a thorough 5-step process, we identified which unique risk factors place one at risk for academic failure. Academic engagement, academic expectations, academic self-efficacy, homework completion, school relevance, school safety, teacher relationships (positive relationship), grade retention, school mobility, and school misbehaviors (negative relationship) were uniquely related to GPA even after controlling for all relevant covariates. Next, a receiver operating characteristic curve was used to determine a cutoff point for determining how many risk factors predict academic failure (GPA < 2.0). Results yielded a cutoff point of 2 risk factors for predicting academic failure, which provides a way for early identification of individuals who are at risk. Further implications of these findings are discussed.  相似文献   
180.
Children build up knowledge about the world and also remember individual episodes. How individual episodes during which children learn new things become integrated with one another to form general knowledge is only beginning to be explored. Integration between separate episodes is called on in educational contexts and in everyday life as a major means of extending knowledge and organizing information. Bauer and San Souci (2010) provided an initial demonstration that 6-year-olds extend their knowledge by integrating between separate but related episodes; the episodes shared a high level of surface similarity. Experiments 1A and 1B of the current research were tests of integration under low and high levels of surface similarity, respectively. In Experiment 1A, when surface similarity of the episodes was low, 6-year-olds integrated between passages of text, yet their performance was not as robust as observed previously. In Experiment 1B, when surface similarity of the episodes was high, a replication of Bauer and San Souci's results was observed. In Experiment 2, we tested whether a "hint" to consult the information learned in the passages improved performance even when surface level similarity was low. The hint had a strong facilitating effect. Possible mechanisms of integration between separate yet related episodes are discussed.  相似文献   
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