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41.
扬琴是一种有着广泛的世界性和民族性的击弦乐器,于明代自国外传至中国。四百多年采扬琴在中国传统音乐文化环境的影响下,不断和民间音乐融合,并在一代代的扬琴艺人的探索和创新中,发展成了具有中国特色的民族乐器,成为世界扬琴三大体系之一的中国扬琴体系,同时形成了中国传统扬琴的四大流派。  相似文献   
42.
In November 2021, a clonal outbreak of Pseudomonas aeruginosa of novel sequence type ST3875 was detected in three patients who died of bloodstream infections in one hospital. By 25 April 2022, the outbreak included 339 cases from 38 hospitals across Norway. Initial hospital reports indicate Pseudomonas infection as the main contributing cause in seven deaths. In March 2022, the outbreak strain was identified in non-sterile pre-moistened disposable washcloths, used to clean patients, from three lots from the same international manufacturer.  相似文献   
43.
Ecological studies often use supermarket location as a proxy measure of the food environment. In this study, we used data on sales at a leading mainstream supermarket chain to explore how area-level supermarket use is associated with overweight and obesity in English adults. Sales data were aggregated to local authority level and joined to a national dataset describing self-reported height and weight and fruit and vegetable consumption. Regression models showed a modest association between higher levels of unhealthy food sales relative to health food sales and increased odds of being overweight and obese. Although effect sizes were small, they persisted after adjustment for area-level deprivation. Supermarket sales data provide additional understanding in the study of food environments and their impact on increasing weight status. Future health policies should consider using ‘big data’ combined with other research methods to address the increasing consumption of unhealthy and highly processed foods.  相似文献   
44.
网络环境下教师指导性活动的设计   总被引:5,自引:1,他引:5  
网络教学为学生的学习提供了丰富的资源,拓延了教学时空的维度,对现有的教学内容、教学手段和教学方法提出了挑战。本文探讨了在此环境下教师指导活动的内容,设计原则及其设计方法等问题。  相似文献   
45.
46.
Magnesium is unique among biological cations. Its volume change from hydrated cation to atomic ion is over an order of magnitude larger than that of any other biological cation. This volume change presents particular problems for a magnesium transport system and suggests that these systems may be significantly different from other classes of ion transport systems. Detailed study of Mg2+ transport in complex organisms is limited by severe technical problems. However, molecular genetic techniques have enabled the isolation of three Mg2+ transport systems from the Gram-negative bacterium Salmonella typhimurium. The MgtA and MgtB transport systems are members of the P-type ATPase superfamily of transporters but possess unique characteristics among members of this family. The CorA transport protein is the first member of an entirely new class of transport proteins. In addition, another completely new family of Mg2+ transport proteins have been identified that is present in both Gram-negative and Gram-positive bacteria. Characterization of these transporters should provide substantial insight into Mg2+ transport and cellular Mg2+ homeostasis.  相似文献   
47.
ABSTRACT

The aim of this paper is to identify and synthesize evidence concerning the most widely used contemporary occupation-focused models including Ecology of human performance; Model of human occupation; Occupational adaptation; and Person–environment–occupational performance. The paper characterizes the amount and type of evidence. Evidence found includes illustrations of how the models can be applied to understand and address a particular problem or population, basic studies that test or expand theoretical concepts, psychometric studies, studies that document therapy outcomes, and studies that examine clinical reasoning and/or practice based on the models. The four models differed widely in the amount and type of evidence available.  相似文献   
48.
Objective: The prevalence of allergic diseases has reached epidemic proportions in the Western world. Although farm-living has been associated with a lower prevalence of asthma and atopy, a marked increase in atopy among rural populations after accession to the European Union has been recently reported in Poland. Here, we aimed to investigate the effect of living environment on the prevalence of atopy and allergic diseases in Polish children. Methods: 400 schoolchildren aged 10–14 years from the capital city (223) and from traditional rural part of the country (177) were recruited from June to November 2011. Data on allergic diseases and symptoms were collected by means of questionnaire and physical examination. Atopy was assessed based on skin prick tests (SPTs) reactivity to inhalant allergens in 350 children. Results: A high discrepancy between the prevalence of allergic symptoms (46.7%) and doctor-diagnosed allergic diseases (25%) was demonstrated (p < 0.0001). Urban children had a higher overall prevalence of allergic diseases and atopy than children living in rural areas, 29.3% versus 17.1% (p = 0.007) and 33.5% versus 20% (p = 0.0045), respectively. However, no significant differences in the rates of particular allergic diseases were noted (p > 0.05). There was higher SPT positivity to trees, grass, corn, weeds, animal dander, and molds in urban children (p < 0.05). Conclusions: Our data support the protective effect of farm-living on the prevalence of atopy and overall allergic diseases, albeit not on particular allergic diseases, in children in Poland. The underlying mechanisms are not identified, but current socioeconomic changes may be responsible.  相似文献   
49.
Our understanding of the genetics of hypertension is incomplete, A great deal has, however, been learned about the role of several »candidate« genes by altering their expression in transgenic and knockout models. Crosses of inbred strains, analyzed in F2 generations, have demonstrated consistent quantitative trait loci, particularly on chromosomes 1, 2 and 10, suggesting significant contributions of some genes in distinct models of rodent hypertension. The effect of these loci has been tested in congenic strains and their interaction underlined in double congenics. The weakness of testing individual animals from F2 crosses is overcome in recombinant inbred strains. In humans, Mendelian models of hypertension have contributed to progress in our understanding of this disease, but have not yet revealed any major gene of essential hypertension. Many association as well as linkage studies of humans have provided useful though somewhat contradictory data. Our renewed effort is oriented towards the discovery of genetic determinants of environmental interaction in hypertension as well as towards the future of pharmacogenomics. This progress will be the basis of future individualized treatment and prevention.  相似文献   
50.
The clinical failure of antimicrobial drugs that were previously effective in controlling infectious disease is a tragedy of increasing magnitude that gravely affects human health. This resistance by pathogens is often the endpoint of an evolutionary process that began billions of years ago in non–disease-causing microorganisms. This environmental resistome, its mobilization, and the conditions that facilitate its entry into human pathogens are at the heart of the current public health crisis in antibiotic resistance. Understanding the origins, evolution, and mechanisms of transfer of resistance elements is vital to our ability to adequately address this public health issue.  相似文献   
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