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朝藿素D的分离和结构   总被引:6,自引:0,他引:6  
从朝鲜淫羊藿(Epimedium koreanum)地上部分分离得到一新黄酮成分(I)和一已知化合物(II)。经光谱解析,证明I的结构为5,7,3',4'-tetrahydroxy-5'-prenylflavone,命名为朝藿素D(epimedokoreanin D);II为2-hydroxy-3,4,6,7-tetramethoxy-9,10-dihydrophenanthren。  相似文献   
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There is a need for occupational therapists to become competent managers in a diverse range of health care settings. In this paper, the author's continuing education course on management which they have conducted at the West Australian Institute of Technology (now Curtin University of Technology) over the past four years. Details of participants, their reasons for attending and their comments on the course are included. The authors emphasise the need for more continuing education in management and the provision of skills for coping with organisational life, in particular in a female dominated profession such as occupational therapy.  相似文献   
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Although the fact that, in general, the US population is living longer is said to be the public health success story of the 20th century, the boom in the population aged 65 years and older is having and will continue to have major implications for all age groups as well as for the nation's health, social, and economic institutions. The concept of productive aging can provide guidance in addressing these implications. The assumptions of productive aging reflect today's reality that older people are repositories of wisdom and experience and important assets for society; relatively healthy, with the potential for maintaining that condition until late in life; capable of making economic and social contributions that benefit themselves, their families, and their communities; and in need of purposeful and meaningful roles and activities in life. A productive aging activity model emphasizes involvement in paid work, volunteerism, education, fitness and exercise, leisure and travel, advocacy and political action, and consumerism. This article discusses the concept of productive aging, a related activity model, and qualitative focus group research undertaken in conjunction with the 1995 White House Conference on Aging. J Am Diet Assoc. 1998;98:1445–1448.  相似文献   
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Ultrastructural studies of cerebral biopsy specimens from patients with various forms of psychomotor retardation and dementia have disclosed pathologic changes in axons and presynaptic or postsynaptic processes. The clinical disorders with lesions in axons and presynaptic terminals are reviewed. Three basic abnormalities have been detected: proliferation of tubulovesicular structures which probably originate from the smooth endoplasmic reticulum, "abnormal" mitochondria, and proliferation of 80 to 100 A filaments. Understanding of the pathogenesis of human disorders associated with axonic or "synaptic" lesions will probably depend on progress in areas of basic biomedical research concerned with the synthesis and turnover of biological membranes and the packaging and secretion of neurotransmitters, elucidation of mechanisms of cytoplasmic streaming and axoplasmic flow, and biophysical and biochemical characteristics and functions of "fibrous" proteins (neurotubules, neurofilaments, pathologic fibrous proteins). In several cases of mental retardation of unknown etiology, abnormal dendritic spines of cortical neurons have been observed with the use of the Golgi method. These dendritic (postsynaptic) disorders have been attributed to defective development ("dysgenesis"). The knowledge provided by ultrastructural analysis of brain tissue from the human disorders of mental retardation or dementia is "still formless, incomplete, lacking the essential threads of connection," and only future developments in lacking neurobiology will make possible the dissection of the primary phenomena from the secretory and probably irrelevant findings.  相似文献   
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