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The enormous growth of the Internet and the World Wide Web has made these two technologies an important potential adjunct to cost-effective health care research and delivery. This article surveys some recent developments in telecommunications, networking and artificial intelligence that are likely to have a significant impact on improving the efficiency and quality of future health care. Issues discussed include: clinical record keeping on the Internet, Internet-assisted medical diagnosis, privacy and security matters, financial transactions, digital money, bandwidth concerns, multimedia (music, audio and video) information delivery via the Internet, intellectual property, and the concept of Information Philanthropy.  相似文献   

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For many years the primary source of information about biological macromolecules was the Protein Data Bank, which is a repository of files containing coordinates of biological macromolecules. Now a variety of databases has been developed in which structures are organized in different ways. Currently available are databases that classify molecules according to their overall structural characteristics or particular features of structures, as well as databases that focus on particular protein families in depth.  相似文献   

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Since the first cell therapeutic study to repair articular cartilage defects in the knee in 1994, several clinical studies have been reported. An overview of the results of clinical studies did not conclusively show improvement over conventional methods, mainly because few studies reach level I of evidence for effects on middle or long term. However, these explorative trials have provided valuable information about study design, mechanisms of repair and clinical outcome and have revealed that much is still unknown and further improvements are required. Furthermore, cellular and molecular studies using new technologies such as cell tracking, gene arrays and proteomics have provided more insight in the cell biology and mechanisms of joint surface regeneration. Besides articular cartilage, cartilage of other anatomical locations as well as progenitor cells are now considered as alternative cell sources. Growth Factor research has revealed some information on optimal conditions to support cartilage repair. Thus, there is hope for improvement. In order to obtain more robust and reproducible results, more detailed information is needed on many aspects including the fate of the cells, choice of cell type and culture parameters. As for the clinical aspects, it becomes clear that careful selection of patient groups is an important input parameter that should be optimized for each application. In addition, the study outcome parameters should be improved. Although reduced pain and improved function are, from the patient's perspective, the most important outcomes, there is a need for more structure/tissue-related outcome measures. Ideally, criteria and/or markers to identify patients at risk and responders to treatment are the ultimate goal for these more sophisticated regenerative approaches in joint surface repair in particular, and regenerative medicine in general.  相似文献   

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Major macroevolutionary events in the history of the oceans are linked to changes in oceanographic conditions and environments on regional to global scales. Even small changes in climate and productivity, such as those that occurred after the rise of the Isthmus of Panama, caused major changes in Caribbean coastal ecosystems and mass extinctions of major taxa. In contrast, massive influxes of carbon at the end of the Palaeocene caused intense global warming, ocean acidification, mass extinction throughout the deep sea and the worldwide disappearance of coral reefs. Today, overfishing, pollution and increases in greenhouse gases are causing comparably great changes to ocean environments and ecosystems. Some of these changes are potentially reversible on very short time scales, but warming and ocean acidification will intensify before they decline even with immediate reduction in emissions. There is an urgent need for immediate and decisive conservation action. Otherwise, another great mass extinction affecting all ocean ecosystems and comparable to the upheavals of the geological past appears inevitable.  相似文献   

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Capsule Populations of birds on farmland are larger and more stable in Hungary than in the UK and may provide baseline targets when planning population restoration programmes in more intensively farmed regions of Europe.

Aims To review the available evidence on farmland bird populations and their changes over the past century in Hungary, and to compare this with similar data for the UK.

Methods Published papers and grey literature were searched to determine long-term bird population trends for birds on farmland in Hungary, and for research evidence on the relationship between farmland management and bird diversity in Hungary.

Results Population density of common farmland birds is higher and trends are more positive in Hungary compared to the UK. These findings correlate with the recent change to generally less intensive agriculture in Hungary. However, while the birdlife associated with farmland in Hungary can be considered to have high diversity and density, it is still lower than it was in the first half of the 20th century and earlier. The few studies available showed that low-intensity traditional management promotes a rich biodiversity in both grasslands and arable systems in Hungary. Agri-environment schemes were introduced when Hungary joined the EU in 2004; however, their influence on biodiversity has not been systematically monitored.

Conclusions Insights emerging from farmland bird research in those European countries which still practice extensive agricultural techniques could be used to set general baseline targets for restoring biodiversity in regions where farmlands are now intensively managed. At the European scale urgent tasks are to: (1) investigate the relationships between management and bird diversity and density on a much wider geographical scale, (2) evaluate the geographical generality of the existing evidence base (which is mainly based on studies conducted in more intensively farmed regions), and (3) enhance the policy impact of conservation research.  相似文献   

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The erythroblastic island: past and future   总被引:5,自引:0,他引:5  
J Bernard 《Blood cells》1991,17(1):5-10; discussion 10-4
The erythroblastic island consists of a macrophage surrounded by erythroblasts of different maturation stages. The cohesion of cells is lost during spreading, so that the islands can no longer be seen in smears. However, in undisturbed preparations, either living or fixed, the islands can be visualized, isolated, cultured, and their function studied. Many questions remain, such as the production of growth factors by the macrophage, the causation of the adhesion of cells forming the islands, the role of calcium in the adhesion, and others. New technical advances, including flow cytometry, immunolabeling, and in situ hybridization will assist in answering these questions.  相似文献   

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J E Boone 《CMAJ》1980,123(12):1201-1202
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