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排序方式: 共有8021条查询结果,搜索用时 15 毫秒
991.
JP Smith 《Canadian Metallurgical Quarterly》1994,34(4):491-496
Aging and health care are the emerging policy issues in the Third World. However, we currently do not have the data to address these issues because economic status and health have not been integrated into a single survey design. This article discusses the rationale for the principal features of an emerging new international survey design which includes integration of younger and older families; reliance on retrospective data; intensive measurement of economic status, health outcomes and utilization and intergenerational transfers; and the combination of a household and community survey. 相似文献
992.
JL Imbs A Castot B Begaud C Larousse JP Blayac JM Alexandre 《Canadian Metallurgical Quarterly》1998,182(7):1383-91; discussion 1392-3
The French drug surveillance system is characterized by: a network of thirty one regional drug surveillance centres, located to provide convenient proximity to health care professionals; a causality assessment method, compulsory for all persons involved in drug surveillance, to assess the causal relationship between an adverse effect and one or more drugs; if necessary, an additional evaluation of the causal relationship will be performed using pharmaco-epidemiology methods; a Technical committee and a National Commission of Drug Surveillance which centralize and assess all the data in order to provide a consensual advice to the relevant authorities on necessary measures, to prevent, or reduce a drug related adverse effect; in the case of an inquiry, the drug surveillance department of the pharmaceutical company and the network of regional drug surveillance centers will pool their data with the aim to exchange information and ideas. 相似文献
993.
Y Kroviarski S Cochet P Martineau JP Cartron O Bertrand 《Canadian Metallurgical Quarterly》1993,633(1-2):273-280
To obtain affinity adsorbents with good mechanical resistance, suitable for the purification of maltose-binding protein (MBP) from Escherichia coli and genetically engineered proteins fused to MBP, a series of supports were prepared by grafting amylose on to agarose by different chemistries. Their capacities for MBP and their abilities to be used at relatively high flow-rates were examined. Efficient supports were most conveniently prepared by coupling amylose to epoxy-activated agarose in an aqueous-organic mixture. 相似文献
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995.
S Launois JL Bizec WA Whitelaw J Cabane JP Derenne 《Canadian Metallurgical Quarterly》1993,6(4):563-575
Hiccup is a forceful, involuntary inspiration commonly experienced by fetuses, children and adults. Its purpose is unknown and its pathophysiology still poorly understood. Short hiccup bouts are mostly associated with gastric distention or alcohol intake, resolve spontaneously or with simple folk remedies and do not require medical attention. In contrast, prolonged hiccup is a rare but disabling condition which can induce depression, weight loss and sleep deprivation. A wide variety of pathological conditions can cause chronic hiccup: myocardial infarction, brain tumour, renal failure, prostate cancer, abdominal surgery etc. Detailed medical history and physical examinations will often guide diagnostic investigations (abdominal ultrasound, chest or brain CT scan...). Gastric and duodenal ulcers, gastritis, oesophageal reflux and oesophagitis are commonly observed in chronic hiccup patients and upper gastrointestinal investigations (endoscopy, pH monitoring and manometry) should be included in the diagnostic evaluation systematically. Etiological treatment is not always available and chronic hiccup treatment has classically relied on metoclopramide and chlorpromazine. Recently, baclofen (LIORESAL) has emerged as a safe and often effective treatment. 相似文献
996.
997.
Dewulf J Van Langenhove H Muys B Bruers S Bakshi BR Grubb GF Paulus DM Sciubba E 《Environmental science & technology》2008,42(7):2221-2232
New technologies, either renewables-based or not, are confronted with both economic and technical constraints. Their development takes advantage of considering the basic laws of economics and thermodynamics. With respect to the latter, the exergy concept pops up. Although its fundamentals, that is, the Second Law of Thermodynamics, were already established in the 1800s, it is only in the last years that the exergy concept has gained a more widespread interest in process analysis, typically employed to identify inefficiencies. However, exergy analysis today is implemented far beyond technical analysis; it is also employed in environmental, (thermo)economic, and even sustainability analysis of industrial systems. Because natural ecosystems are also subjected to the basic laws of thermodynamics, it is another subject of exergy analysis. After an introduction on the concept itself, this review focuses on the potential and limitations of the exergy conceptin (1) ecosystem analysis, utilized to describe maximum storage and maximum dissipation of energy flows (2); industrial system analysis: from single process analysis to complete process chain analysis (3); (thermo)economic analysis, with extended exergy accounting; and (4) environmental impact assessment throughout the whole life cycle with quantification of the resource intake and emission effects. Apart from technical system analysis, it proves that exergy as a tool in environmental impact analysis may be the most mature field of application, particularly with respect to resource and efficiency accounting, one of the major challenges in the development of sustainable technology. Far less mature is the exergy analysis of natural ecosystems and the coupling with economic analysis, where a lively debate is presently going on about the actual merits of an exergy-based approach. 相似文献
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前脂质体技术在食品原料包埋的应用 总被引:2,自引:0,他引:2
Jean Pierre Arnaud 《中国食品工业》1997,(12):36-37
<正> 长期以来,脂质体大都应用于化妆品和医药领域中,直至近年才在农业和食品工业上,显示出巨大的应用潜力。借助于前脂质体技术(Pro-Liposome Approach)的应用,生产商可以采用脂质体包埋许多不同种类的化合物,如酶、香精、矿物质和维生素等,有助提高产率和产品的质量。 前脂质体技术包埋原理 前脂质体技术的开发,为脂质体的形 相似文献