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《Zoologica scripta》2009,38(S1):33-40
From the time of Linnaeus forward, it has been appreciated that collections, not least marine biological collections, are fundamental to the understanding of the biodiversity of life on earth, especially when they contain type specimens which define individual species. Historical collections are particularly rich in types and also represent a model of the biodiversity of marine life at the time of the collection, often centuries ago. The taxonomic and systematic importance of collections is well appreciated, as is the significance of time series of data in this period of anthropogenic environmental change. The application of new techniques increases the value of collected material even further, for example, molecular biology techniques allowing the recognition of new (often cryptic) taxa and their distributions, and stable isotope analyses releasing information on past and present ontogenies, geographical distributions and diets. Moreover the new era of information technology with associated digitization enables the release of the information stored in the collections to the scientists of the world. 相似文献
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Jeffrey A. McNeely 《Biodiversity and Conservation》1994,3(5):390-405
Since the first national park was created at Yellowstone in the USA in 1872, over 8500 protected areas have been established worldwide. Virtually all countries have seen the wisdom of protecting areas of outstanding importance to society, and such sites now cover over 5% of Earth's land surface. However, many of these protected areas exist only on paper, not on the ground. Most are suffering from a combination of threats, including pollution, over-exploitation, encroachment, poaching, and many others. In a period of growing demands on resources and shrinking government budgets, new approaches are required to ensure that protected areas can continue to make their contributions to society. First and foremost, protected areas must be designed and managed in order to provide tangible and intangible benefits to society. This will involve integrating protected areas into larger planning and management frameworks, linking protected areas to biodiversity and climate change, promoting greater financial support for protected areas, and expanding international cooperation in the finance, development and management of protected areas. 相似文献
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The specialty of tropical medicine originated from the needs of the colonial era and is removed from many of the health care requirements of tropical countries today. Tropical medicine concentrates on parasitic diseases of warm climates, although other infections and diseases related to poverty rather than climate dominate medicine in developing countries challenged by population pressure, civil strife, and migration. In the new century, tropical medicine would best be absorbed into the specialty of infectious diseases, which should incorporate parasitic diseases, travel medicine, and sexually transmitted diseases. Pressing questions for health care and research in developing countries concern the provision of appropriate services for problems such as HIV/AIDS, tuberculosis, sexually transmitted diseases, and injuries. The question of how to provide appropriate clinical care in resource poor settings for the major causes of morbidity and premature mortality has been neglected by donors, academic institutions, and traditional tropical medicine. 相似文献
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Traditionally, studies of scientific productivity are biased in two ways: they are based on Current Contents, an index centered in British and American journals, and they seldom correct for population size, ignoring the relative effort that each society places in research. We studied national productivity for biology using a more representative index, the Biological Abstracts, and analyzed both total and relative productivity. English dominates biological publications with 87% (no other individual language reaches 2%). If the USA is considered a region by itself, it occupies the first place in per capita production of biology papers, with at least twice the productivity of either Asia or Europe. Canada, Oceania and Latin America occupy an intermediate position. The global output of scientific papers is dominated by Europe, USA. Japan, Canada, China and India. When corrected for population size, the countries with the greatest productivity of biology papers are the Nordic nations, Israel, Switzerland, Netherlands, Australia, Saint Lucia and Montserrat. The predominance of English as the language of biological research found in this study shows a continuation of the trend initiated around the year 1900. The large relative productivity of the USA reflects the importance that American society gives to science as the basis for technological and economic development, but the USA's share of total scientific output has decreased from 44% in 1983 to 34% in 2002, while there is a greater growth of science in India, Japan and Latin America, among others. The increasing share obtained by China and India may reflect a recent change in attitude towards funding science. The leadership of Nordic nations, Israel, Switzerland, Netherlands and Australia can be explained by cultural attitude. Apparently, a positive trend is emerging in Latin America, where Chile improved its ranking in per capita productivity but Argentina, Costa Rica, Uruguay, Brazil and Cuba fell. Nevertheless, the most productive countries in total number of papers are Brazil, Mexico and Argentina: large countries with a long tradition of funding scientific research. 相似文献
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Maize selection passes the century mark: a unique resource for 21st century genomics 总被引:5,自引:0,他引:5
The Illinois Long-Term Selection Experiment for grain protein and oil concentration in maize (Zea mays) is the longest continuous genetics experiment in higher plants. A total of 103 cycles of selection have produced nine related populations that exhibit phenotypic extremes for grain composition and a host of correlated traits. The use of functional genomics tools in this unique genetic resource provides exciting opportunities not only to discover the genes that contribute to phenotypic differences but also to investigate issues such as the response of plant genomes to artificial selection, the genetic architecture of quantitative traits and the source of continued genetic variation within domesticated crop genomes. 相似文献
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Haldane's Rule (HR), which states that 'when in the offspring of two different animal races one sex is absent, rare, or sterile, that sex is the heterozygous (heterogametic) sex', is one of the most general patterns in speciation biology. We review the literature of the past 15 years and find that among the ~85 new studies, many consider taxa that traditionally have not been the focus for HR investigations. The new studies increased to nine, the number of 'phylogenetically independent' groups that comply with HR. They continue to support the dominance and faster-male theories as explanations for HR, although due to increased reliance on indirect data (from, for example, differential introgression of cytoplasmic versus chromosomal loci in natural hybrid zones) unambiguous novel results are rare. We further highlight how research on organisms with sex determination systems different from those traditionally considered may lead to more insight in the underlying causes of HR. In particular, haplodiploid organisms provide opportunities for testing specific predictions of the dominance and faster X chromosome theory, and we present new data that show that the faster-male component of HR is supported in hermaphrodites, suggesting that genes involved in male function may evolve faster than those expressed in the female function. 相似文献
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J. D. Wolfensohn 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》1999,354(1392):1943-1948
By many people, the 20th century will be remembered as an era of great achievement in human endeavour, and of enormous economic growth and prosperity. Achievements in medical research, from eradicating infectious diseases to laser surgery; in engineering, from the transistor to space exploration; and in economic development have all contributed to greater well being in the world at the end of the 20th century. Among the challenges to development identified by the World Bank in the coming decades will be managing the twin processes of globalization and localization, as well as post-conflict reconstruction. These will form the backdrop of the Bank''s main focus of creating a world free of poverty. 相似文献
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Javitt NB 《Steroids》2008,73(2):149-157
A major focus for the 21st century are the sterol intermediates in cholesterol synthesis and their metabolites. No longer considered inactive way stations in their transformation to cholesterol, both physiologic and pathophysiologic studies, though early in their development, indicate novel biologic roles for these sterols, and their oxysterol metabolites that bypass cholesterol, the expected end product. A major impetus for further inquiry is the recognition that in genetically determined errors in cholesterol synthesis such as Smith-Lemil-Opitz syndrome, the phenotypic effects on the developing fetus are not solely attributable to the lack of cholesterol but the accumulation of 7-dehydrocholesterol and its 27-hydroxy metabolite. This view is now supported by a new mouse model, the double knockout Insig1 & 2 (insulin-induced genes 1 & 2) in which lack of the protein product results in a greater production of lanosterol compared to cholesterol during fetal life with severe dysmorphic consequences. Further support can be derived from in vitro studies of the Sonic hedgehog signaling pathway, essential for normal morphogenesis in the central nervous system and perhaps other organs, which may require the local presence of oxysterols for full expression. Future studies that can delineate the specific role of a sterol intermediate or its metabolite require a paradigm shift away from the generic use of oxysterols as a class of compounds to a focus on specific sterols that can be expected in tissues and techniques for mimicking the local environment. Another class of oxysterols are those arising by photoxidation, now considered to be an expected event generated by the photons of visible blue light and therefore pari passu with normal vision. The sequence of events from peroxides of cholesterol to hydroxy and keto derivatives is the signature of singlet oxygen as opposed to free radicals and other mechanisms for generating reactive oxygen species. Perhaps surprisingly, the retina expresses CYP 27A1 and CYP 46A1, enzymes with broad substrate specificity for ring-modified sterols, implying that, in addition to a rich blood supply for disposing of potentially toxic oxysterols, they can be detoxified locally. Recognition that the retina has nuclear receptors similar to those found in other tissues raises the possibility that the sterols that are generated may function in their traditional role as ligands for modulating gene expression but other, nonligand, activities can be expected since other proteins such as the oxysterol-binding proteins exist and are considered to have biologic activities. To critically evaluate these potentially new biologic roles for oxysterols a need exists for the synthesis and utilization of the expected naturally occurring metabolites rather than available surrogates that may not be truly representative of their tissue effects and to utilize analytical techniques that can identify their existence at the expected concentrations in tissues. 相似文献
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Hillman H 《Physiological chemistry and physics and medical NMR》2002,34(2):145-7; discussion 148-50
The aim of biology is the study of the properties of cells in living intact animals. Many steps of research procedures in biochemistry change the entropy, and therefore, the free energy of the chemical reactions from those in vivo. Sections prepared for histology, histochemistry, electron microscopy and immunocytochemistry, yield limited information about the original cells in life, although their problems have been documented. Approaches to the biological and histological difficulties are suggested. 相似文献