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1.
Bergmann R  Pietzsch J 《Amino acids》2005,29(4):355-376
Summary. Positron emission tomography (PET) is a 3-dimensional imaging technique that has undergone tremendous developments during the last decade. Non-invasive tracing of molecular pathways in vivo is the key capability of PET. It has become an important tool in the diagnosis of human diseases as well as in biomedical and pharmaceutical research. In contrast to other imaging modalities, radiotracer concentrations can be determined quantitatively. By application of appropriate tracer kinetic models, the rate constants of numerous different biological processes can be determined. Rapid progress in PET radiochemistry has significantly increased the number of biologically important molecules labelled with PET nuclides to target a broader range of physiologic, metabolic, and molecular pathways. Progress in PET physics and technology strongly contributed to better scanners and image processing. In this context, dedicated high resolution scanners for dynamic PET studies in small laboratory animals are now available. These developments represent the driving force for the expansion of PET methodology into new areas of life sciences including food sciences. Small animal PET has a high potential to depict physiologic processes like absorption, distribution, metabolism, elimination and interactions of biologically significant substances, including nutrients, ‘nutriceuticals’, functional food ingredients, and foodborne toxicants. Based on present data, potential applications of small animal PET in food sciences are discussed.  相似文献   

2.
从科研论文量看世界生命科学的发展   总被引:2,自引:0,他引:2  
高柳滨  陈桦  江晓波 《生命科学》2003,15(4):251-254
应用美国ESI基本科学指标数据库,对1993年至2003年世界科研产出成果进行统计分析,反映国内外生命科学重点研究领域和学科分布特点,揭示我国与国外相比存在的差距。从文献计量学角度,对我国生命科学的发展提出了建设性意见。  相似文献   

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This brief article outlines some difficulties as well as benefits in conducting randomized controlled trials in social science settings especially in developing countries. Some of the historical developments are summarized and certain applications in health sciences are discussed from methodological and policy standpoints.  相似文献   

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The World Health Organization (WHO) has recently published a new research agenda for radiofrequency fields. The document lists high priority and other research needs for health effects research, subdivided into epidemiology, human studies, animal studies, cellular studies and mechanisms, and for social science research.  相似文献   

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We describe nutritional peptidomics for discovery and validation of bioactive food peptide and their health effects. Understanding nature and bioactivity of nutritional peptides means comprehending an important level of environmental regulation of the human genome, because diet is the environmental factor with the most profound life-long influence on health. We approach the theme from three angles, namely the analysis, the discovery and the biology perspective. Food peptides derive from parent food proteins via in vitro hydrolysis (processing) or in vivo digestion by various unspecific and specific proteases, as opposed to the tryptic peptides typically generated in biomarker proteomics. A food bioactive peptide may be rare or unique in terms of sequence and modification, and many food genomes are less well annotated than e.g. the human genome. Bioactive peptides can be discovered either empirically or by prediction: we explain both the classical hydrolysis strategy and the bioinformatics-driven reversed genome engineering. In order to exert bioactivity, food peptides must be either ingested and then reach the intestine in their intact form or be liberated in situ from their parent proteins to act locally, that is in the gut, or even systemically, i.e. through the blood stream. This article is part of a Special Section entitled: Understanding genome regulation and genetic diversity by mass spectrometry.  相似文献   

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基因组研究与生命科学工业的崛起   总被引:7,自引:0,他引:7  
人类基因组的全序列测定预计可提前两年于2003年完成,特别是基因组内的蛋白质编码序列将更早测定。私人财团斥巨资进入这个领域,并望抢得先手,这意味着基因组研究可创造巨大财富。在过去几年里,国际上一批知名的大型制药集团和化学工业公司已在基因组研究领域内投入大量资金,并形成了一个新的产业部门,即生命科学工业。制药工业是生命科学工业的主要支柱之一,与基因组研究的关系特别密切。药物基因组学研究表明,药物的疗效与患者的基因型相关,因此,今后的药物生产要考虑到药物投放地区人群中有关的等位基因的频率,医疗处方也将因人而异而趋向个人化。比较基因组学研究则有助于从模式生物的资料指出与疾病可能相关的基因,可以此作为靶标来设计药物。  相似文献   

8.
Random matching between individuals, or the complete-mixing model, is often assumed in analyzing evolutionary or population dynamics in ecology and game theory or other models in social sciences. Making and analyzing a model is not difficult under this simple assumption. However spatial- or network-structured populations, including the lattice model and the power-law network, are more realistic for many ecological and social phenomena than the complete-mixing model. In this review, I will show first that a lattice model can be useful in investigating the effect of neighborhood interactions on the dynamics, not only of plants and forests, but also of animal and human societies. Second, the lattice model promotes the evolution of spiteful behavior, even though it is well-known that the lattice model promotes the evolution of cooperation. Finally, different social networks result in traits, such as social norms, spreading at different speeds.  相似文献   

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Social stress can cause physical and mental harm. It is therefore not surprising that public health policy makers have sought to identify and implement policies aimed at tackling this social ill. A frequently prescribed remedy is to reduce social stress by reducing income inequality, which is typically measured by the Gini coefficient. Decomposing the coefficient into a measure of a population’s social stress and a population’s income makes it possible to show that steps taken to lower the coefficient can actually exacerbate social stress. We formulate conditions under which lowering the Gini coefficient coincides with increasing social stress. If the aim of public policy is to improve public health and increase social welfare, and if social welfare is reduced by social stress, then lowering the Gini coefficient may not be the right course of action.  相似文献   

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The paired source and sink concepts are used increasingly in ecology and Earth sciences, but they have evolved in divergent directions, hampering communication across disciplines. We propose a conceptual framework that unifies existing definitions, and review their most significant consequences for the various disciplines. A general definition of the source and sink concepts that transcends disciplines is based on net flows between the components of a system: a source is a subsystem that is a net exporter of some living or non‐living entities of interest, and a sink is a net importer of these entities. Sources and sinks can further be classified as conditional and unconditional, depending on the intrinsic propensity of subsystems to either produce (source) or absorb (sink) a surplus of these entities under some (conditional) or all (unconditional) conditions. The distinction between conditional and unconditional sources and sinks, however, is strongly context dependent. Sources can turn into sinks, and vice versa, when the context is changed, when systems are subject to temporal fluctuations or evolution, or when they are considered at different spatial and temporal scales. The conservation of ecosystem services requires careful consideration of the source?sink dynamics of multiple ecosystem components. Our synthesis shows that source?sink dynamics has profound consequences for our ability to understand, predict, and manage species and ecosystems in heterogeneous landscapes.  相似文献   

14.
Anthropologists and sociologists offer numerous critiques of bioethics. Social scientists criticize bioethicists for their arm-chair philosophizing and socially ungrounded pontificating, offering philosophical abstractions in response to particular instances of suffering, making all-encompassing universalistic claims that fail to acknowledge cultural differences, fostering individualism and neglecting the importance of families and communities, and insinuating themselves within the “belly” of biomedicine. Although numerous aspects of bioethics warrant critique and reform, all too frequently social scientists offer ungrounded, exaggerated criticisms of bioethics. Anthropological and sociological critiques of bioethics are hampered by the tendency to equate bioethics with clinical ethics and moral theory in bioethics with principlist bioethics. Also, social scientists neglect the role of bioethicists in addressing organizational ethics and other “macro-social” concerns. If anthropologists and sociologists want to provide informed critiques of bioethics they need to draw upon research methods from their own fields and develop richer, more informed analyses of what bioethicists say and do in particular social settings.  相似文献   

15.
随着经济全球化和科技的迅速发展,国家对高层次复合型人才的需求日益增长,因此对生命科学专业硕士研究生有了更高的要求。在大力推进素质教育的背景下,通过分析生命科学专业课程体系的现状及存在的问题和本专业硕士课程改革的必要性,结合安徽师范大学生科院的生命科学专业一级硕士点实际情况,对硕士课程设置的改革与实践进行了探讨,以期为生命科学一级学科硕士授权点专业课程的改革提供基础资料。  相似文献   

16.
Detection and analysis of genetic variation can help us to understand the molecular basis of various biological phenomena in plants. Since the entire plant kingdom cannot be covered under sequencing projects, molecular markers and their correlation to phenotypes provide us with requisite landmarks for elucidation of genetic variation. Genetic or DNA based marker techniques such as RFLP (restriction fragment length polymorphism), RAPD (random amplified polymorphic DNA), SSR (simple sequence repeats) and AFLP (amplified fragment length polymorphism) are routinely being used in ecological, evolutionary, taxonomical, phylogenic and genetic studies of plant sciences. These techniques are well established and their advantages as well as limitations have been realized. In recent years, a new class of advanced techniques has emerged, primarily derived from combination of earlier basic techniques. Advanced marker techniques tend to amalgamate advantageous features of several basic techniques. The newer methods also incorporate modifications in the methodology of basic techniques to increase the sensitivity and resolution to detect genetic discontinuity and distinctiveness. The advanced marker techniques also utilize newer class of DNA elements such as retrotransposons, mitochondrial and chloroplast based microsatellites, thereby revealing genetic variation through increased genome coverage. Techniques such as RAPD and AFLP are also being applied to cDNA-based templates to study patterns of gene expression and uncover the genetic basis of biological responses. The review details account of techniques used in identification of markers and their applicability in plant sciences.  相似文献   

17.
Several Vietnamese seaweed species have economic importance as food for humans, as industrial materials, as ingredients in traditional medicine, and as biofertilizers. The nutritional values of nine representative Vietnamese seaweed species were analyzed. In this report, all of the species studied are rich in proteins, lipids (especially polyunsaturated fatty acids), vitamins, pigments, and macro- and micro-elements. The effect of the physiological activities of the green alga, Ulva reticulata, on hepatic fatty acid metabolism were examined in mice. The results indicate that Vietnamese seaweeds are abundant and have high quality materials for industrial and agricultural purposes. Presented at the 6th Meeting of the Asian Pacific Society of Applied Phycology, Manila, Philippines.  相似文献   

18.
BackgroundBlack pericarp rice has recently become popular among rice consumers for its diverse health benefits specially anti-cancer effect. Cyanidin-3-Glucosides (C3G), an prominant bioactive component of anthocyanins which is abundantly present in black pericarp rice.ObjectivesWe investigated, how effectively it can be used to fortify Cyanidin-3-Glucosides (C3G) content in red and white pericarp polished rice or rice based bakery products for more nutritional value.MethodIn the present study, we have characterized several black pericarp rice cultivars along with some red pericarp and white pericarp rice cultivars by physicochemical including mineral profiling, and quantified the C3G by UFLC and LCMS.ResultsC3G content was significantly reduced from raw rice to cooked rice condition. All the black pericarp rice cultivars synthesized C3G, while this content was not detected in red and white pericarp rice cultivars. However, when 25% of black pericarp rice were mixed with 75% red or white pericarp polished rice, C3G content was significantly retained in cooked rice conditions. Formulation of rice-based bakery food product using black pericarp rice powder was also remarkably retained the C3G content as compared to that of cooking. Black rice is harder in texture, difficult to digest and needs higher energy for cooking. Therefore, we tried to circumvent these challenges by fortifying 25% of black pericarp rice with white or red pericarp rice.ConclusionFortification of C3G enriched black rice (25%) with red or white pericarp rice (75%) might bring a better nutritional quality in both cooking and baking condition. This may lead a way to the effective management of the non-communicable disease such as cancer for common rice consuming population.  相似文献   

19.
Selection pressure from health risk is hypothesized to have shaped adaptations motivating individuals to attempt to become valued by other individuals by generously and recurrently providing beneficial goods and/or services to them because this strategy encouraged beneficiaries to provide costly health care to their benefactors when the latter were sick or injured. Additionally, adaptations are hypothesized to have co-evolved that motivate individuals to attend to and value those who recurrently provide them with important benefits so they are willing in turn to provide costly care when a valued person is disabled or in dire need. Individuals in egalitarian foraging bands can provide a number of valuable benefits, such as defense, diplomacy, food, healing, information, technical skill, or trading savvy. We therefore expect that humans have evolved psychological mechanisms motivating the pursuit and cultivation of a difficult-to-replace social role based on the provisioning of a benefit that confers a fitness advantage on its recipients. We call this phenomenon social niche specialization. One such niche that has been well-documented is meat-sharing. Here we present cross-cultural evidence that individuals cultivate two other niches, information and tool production, that serve (among other things) to buffer health risk. Michelle Scalise Sugiyama studied at the Center for Evolutionary Psychology at the University of California, Santa Barbara, where she received her Ph.D. in literature in 1997. She is currently an affiliate of the English Department and the Institute for Cognitive and Decision Sciences at the University of Oregon, Eugene, and also directs the Cognitive Cultural Studies branch of the Human Universals Project at the Center for Evolutionary Psychology. Her work attempts to understand narrative and other art behaviors in terms of the cognitive architecture that underlies them and the ancestral conditions under which they emerged; published results can be found in Human Nature, Evolution and Human Behavior, Philosophy and Literature, and Mosaic. Lawrence Sugiyama holds a joint appointment in the Anthropology Department and the Institute for Cognitive and Decision Sciences at the University of Oregon, Eugene. He did his graduate work at the Center for Evolutionary Psychology at the University of California, Santa Barbara, where he cofounded the Human Universals Project and the Ecuadorian Oriente Research Station, which he now directs. His research among the Shiwiar, Yora, and Yanomamo examines health risk, cooperation, reciprocity, subsistence, and life history patterns among contemporary forager-horticulturalists, with the ultimate goal of furthering our understanding of pat selection pressures and the psychology evolved to surmount them. Published results can be found in Proceedings of the National Academy of Science, American Journal of Physical Anthropology, and Adaptation and Human Behavior: An Anthropological Perspective.  相似文献   

20.
Major economic transitions typically entail changes in the availability of and purchasing power for different types of foods leading to long-term changes in the composition of the diet. Bulgaria, a former Eastern Bloc country, underwent a difficult and protracted transition from a centralized to market economy with acute economic crises and a much slower recovery of income levels than in Poland, the Czech Republic, and Hungary. Using annual data from the Bulgarian National Household Survey, we study changes in the reported consumption of major foods (excluding alcoholic drinks) and their constituent macronutrients from 1985 to 2002, examining also the differences in dietary patterns between the period prior to and following the transition. The consumption of most major food items decreased, resulting in a fall in per capita energy consumption of 429 kcal/day (1.80 MJ/d), following the economic transition of 1991. As expected, the consumption of foods that were more expensive per unit of energy decreased greater than cheaper foods, -34% for animal products and -19% for visible fats, but only -10% for carbohydrates. These changes are related to the changes in income and market prices as well as the general negative trend in economic growth and hyperinflation in the mid-1990s. Thus, Bulgaria experienced a decrease in food consumption without significant changes in the dietary pattern following the economic transition of 1991. The fact that part of this decline may be attributed to continued economic challenges suggests that future transitions in the diet may be expected as economic development proceeds.  相似文献   

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