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The process of ageing and the relevant scientific disciplines are influenced by societal values und priorities. Values are the object of scientific and public reflection mainly in times of strong changes and obvious conflicts. The article discusses fundamental social and cultural changes from collective integration to personal freedom and autonomy. The focus of this paper is directed towards the impact of the consequences and contradictions of such cultural changes on the process of ageing and of ageing research.  相似文献   

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Ohne Zusammenfassung  相似文献   

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There is a lot of evidence that age-associated alterations of the mitochondrial genome occur, especially in postmitotic tissues such as brain, heart and skeletal muscle. These alterations are supposed to be a result of an attack of free radicals generated as normal byproducts of oxidative phosphorylation and lead to damage of proteins, lipids, and DNA. The alterations of mtDNA include oxidative damage of base pairs, point mutations, large-scale deletions or duplications. The 4977 bp deletion or "common deletion" reveals an age-dependent accumulation in postmitotic tissues, but not in fast-dividing tissues such as blood cells. In addition, it is observed that a tissue-specific accumulation occurs with the highest abundance in the basal ganglia, followed by skeletal muscle, heart, and lowest in cerebellar tissue. Third, pathological alterations of specific tissue, like ischemia/reperfusion events, display a pronounced accumulation of the deletion compared to age-matched controls. Because there are many mtDNA mutations, further analysis of all alterations of mtDNA will elucidate its role in the phenomenon of aging. Despite some criticisms of this free radical theory of aging, there is a lot of experimental evidence to support the important role of mitochondria in organismal aging.  相似文献   

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The focus is on the basic biological-genetic and social-cultural architecture of human development across the life span. The starting point is the frame provided by past evolutionary forces. A first conclusion is that for modern times and the relative brevity of the time windows involved in modernity, further change in human functioning is primarily dependent on the evolution of new cultural forms of knowledge rather than evolution-based changes in the human genome. A second conclusion concerns the general architecture of the life course. Three governing lifespan developmental principles coexist. First, because long-term evolutionary selection evince a negative age correlation, genome-based plasticity and biological potential decrease with age. Second, for growth aspects of human development to extend further into the life span, culture-based resources are required at ever increasing levels. Third, because of age-related losses in biological plasticity and negative effects associated with some principles of learning (e.g., negative transfer), the efficiency of culture is reduced as lifespan development unfolds. Joint application of these principles suggests that the lifespan architecture becomes more and more incomplete with age. Three examples are given to illustrate the implications of the lifespan architecture outlined. The first is a general theory of development involving the orchestration of three component processes and their age-related dynamics: Selection, optimization, and compensation. The second example is theory and research on lifespan intelligence that distinguishes between the biology-based mechanics and culture-based pragmatics of intelligence and specifies distinct age gradients for the two categories of intellectual functioning. The third example considers the goal of evolving a positive biological and cultural scenario for the last phase of life (fourth age). Because of the general lifespan architecture outlined, this objective becomes increasingly difficult to achieve. In fact, for other reasons (such as the obsolescence created by rapid technological change) the 21st century can be considered as the century of the permanently incomplete mind. The advent of intervention genetics creates a new scenario with promise and despair. Promise because of the possibility to complete the biological-genetic architecture of the life course through a priori and a posteriori genetic engineering, despair because of a new schism created by the risk of dissociation of the time course of genetic intervention and cultural evolution. For the first time in history, humankind is truly in charge of it's biocultural "natural" destiny.  相似文献   

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The results of the determination of 24 basic blood chemistry variables from 262 men and 239 women, half of each group 44.4 +/- 0.9 and 63.0 +/- 0.9 (men) and 44.4 +/- 0.9 and 62.8 +/- 0.8 years old (women), resp., are compared. In men, only 6 analytes show significant differences between the age groups: Alanine aminotransferase decreases, aspartate aminotransferase decreases, iron decreases with p < 0.05; sodium increases, calcium decreases, protein (serum) decreases with p < 0.001. In women, 16 analytes, compared between both groups, are significantly different: Urea, uric acid, creatinine, triglycerides, total cholesterol, LDL cholesterol, LDL-C/HDL-C ratio, alanine aminotransferase, alkaline phosphatase, gamma-glutamyltransferase, sodium and ferritin are increased in the older group, whereas HDL cholesterol, iron, transferrin, and total protein are decreased. The sex differences are more distinct in the group of 44 years old persons than in the 63 years old one. These results will be completed by the comparison with the evaluation of the stored laboratory values of 9923 patients between 20 and 89 years old.  相似文献   

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