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61.
The polyadenylation code: a unified model for the regulation of mRNA alternative polyadenylation 总被引:3,自引:2,他引:1
The majority of eukaryotic genes produce multiple mRNA isoforms with distinct 3′ ends through a process called mRNA alternative polyadenylation (APA). Recent studies have demonstrated that APA is dynamically regulated during development and in response to environmental stimuli. A number of mechanisms have been described for APA regulation. In this review, we attempt to integrate all the known mechanisms into a unified model. This model not only explains most of previous results, but also provides testable predictions that will improve our understanding of the mechanistic details of APA regulation. Finally, we briefly discuss the known and putative functions of APA regulation. 相似文献
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Judith Owens Darrel Drobnich Allison Baylor Daniel Lewin 《Mind, Brain, and Education》2014,8(4):182-213
In response to the scientific evidence documenting both profound developmental changes in sleep and circadian biology during adolescence and the myriad of negative health, performance, and safety outcomes risks associated with chronic sleep loss, at least 70 public school districts in the United States, representing approximately 1,000 schools, have successfully implemented a delay in high school start times. However, despite the compelling evidence supporting school start time change as a key strategy in addressing the epidemic of adolescent sleep loss, many school districts across the country with early high school start times have not considered the option to implement later bell schedules for adolescents. Moreover, while the current scientific literature has clearly documented the positive outcomes associated with delayed high school start times, these studies contain limited information regarding the process by which school districts consider, approve and implement bell schedule changes. Thus, this in‐depth examination of those school districts that have been successful in changing their bell schedules is intended to support the efforts of other districts in various stages of contemplating this measure. We utilized a multi‐pronged approach (literature review, case studies, telephone interviews, online survey) to summarize the experiences of school districts across the United States in regard to challenges faced, strategies employed, and lessons learned in the hope that this information will be a useful tool for other school districts looking to chart a course forward to promote the health, safety, and academic opportunities of their students. 相似文献
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The international perceptions of Japanese young adults were explored in 172 professional education students in two Tokyo colleges. They classified 30 nations according to their “current” and “future” affinity to Japan. Little difference was detected in the Q-sorts between institutions arid sexes, while the “current” and “future” sorts correlated .96 with each other. In cluster analyses, many two-nation units (e.g., Czechoslovakia-Yugoslavia) were found to be the building blocks for the overall pattern. The total configuration consisted of three broad groups: mostly Western European nations, problematical nations (China, Russia, Israel, Egypt, etc.), and remote and neutral nations. Structurally, the results were similar to those for American young adults, but the contents were different. The notion of cultural metastereotypes thus received tentative support. 相似文献
69.
Davis KS Burgeson CR Brener ND McManus T Wechsler H 《Research quarterly for exercise and sport》2005,76(2):202-211
The authors analyzed data from the School Health Policies and Programs Study 2000 to assess the associations between the presence of a district physical education coordinator and district-level physical education policies and practices recommended by federal government agencies and national organizations. The authors also examined the relationship between teacher qualifications and staff development related to physical education and self-reported implementation of recommended teachingpractices. District-level data were collected by self-administered mail questionnaires from a nationally representative sample of school districts. Classroom-level data were collected by computer-assisted personal interviews with teachers of randomly selected classes in elementary schools and randomly selected required physical education courses in middle/junior high and senior high schools. Nearly two thirds (62.2%) of districts had a physical education coordinator, and those were generally more likely than other districts to report having policies and practices that corresponded with national recommendations for high-quality physical education programs. More than two thirds of teachers (66.9%) met the criteria for teacher qualifications based on their education and certification. These teachers were more likely than others to report use of certain recommended physical education teaching practices. Teachers who participated in staff development also were more likely to use recommended teaching practices in their classrooms. Using a district physical education coordinator and teachers with appropriate qualifications as well as offering staff development opportunities on physical education may enhance school physical education programs. 相似文献
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