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991.
We discuss gigabit network applications enabled by “Mission to Planet Earth”, an international effort to monitor the Earth as a system. We describe the design of a network architecture to support applications developed as part of this program; introduce a new component, public access resource centers (PARCs); and discuss how PARCs would facilitate access by users outside the traditional research community. We also describe how a particular class of users, agriculture users, might benefit from access to data collected as part of the Mission to Planet Earth program and delivered in a value-added form to them by a so-called AgPARC. The suggested architecture requires the deployment of high-bandwidth networks  相似文献   
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A sensitive sandwich enzyme-linked immunoadsorbent assay (ELISA) for determination of exogenous glucagon-like peptide-1(7-36)amide (GLP-1(7-36)amide) in plasma samples from pharmacokinetic studies is described. The assay employs an N-terminally directed antibody and a C-terminally directed antibody. The ELISA has a working range from 10 to 500 pmol l-1, and can be applied to plasma samples from humans, dogs, pigs, minipigs, cats, rabbits, and rats. The assay was compared to a validated radioimmunoassay (RIA), employing an antibody directed against the mid-region of GLP-1. After s.c. administration of GLP-1(7-36)amide, the plasma immunoreactivity of GLP-1 (P-GLP-1-IR) measured by ELISA was markedly lower than P-GLP-1-IR measured by RIA. After HPLC fractionation of plasma samples with subsequent RIA and ELISA analyses of the fractions, this difference was shown to be due to cross reaction with biologically inactive fragments of GLP-1(7-36)amide in the RIA but not in the ELISA.  相似文献   
996.
Inhalants, a chemically heterogeneous group of psychoactive substances found in adhesives, lighter fluids, spray paints, cleaning fluids and typewriter correction fluid, may be used by up to 10% of young people. This article reviews the health effects, epidemiology, risk of other substance use and addiction and psychiatric co-morbidity associated with the practice of inhalant use.  相似文献   
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The aim of the present work was to study the possible association of some class I, II MHC gene products with variations in the clinico-pathological outcome of human schistosomiasis mansoni as well as with the variability in immune responsiveness. The study was carried out on 47 patients with schistosomiasis mansoni and 20 healthy volunteers served as control group for the immunological parameters and 200 subjects for the genetic studies. The following were determined: class I, II HLA typing, serum IgG, IgM, C3c, immediate intradermal test and passive haemagglutination using S mansoni worm antigen, T lymphocyte subsets, delayed intradermal test and leukocyte migration inhibition using phytohaemagglutinin (PHA) and soluble egg antigen (SEA) of S mansoni. A statistically significant association was found between HLA-B5 and DR3 and with the occurrence of hepatosplenic disease; this phenotype also correlated with changes in T lymphocyte subsets and high immune reactivity, both humoral and cell mediated. HLA-DQI was also associated with failure to develop hepatosplenic disease. The present study consolidates also the view of the important role of host immune reactivity in the clinical outcome of schistosomiasis mansoni and demonstrates the contribution of the genetic impact on both clinical and immunological heterogeneity of the disease.  相似文献   
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Congenital infections of pigs were induced with two ruminant-type pestiviruses isolated from pigs. One of the viruses was bovine viral diarrhoea virus-like and the other border disease virus-like. Both produced symptoms similar to those observed with low virulence strains of classical swine fever virus. A striking effect of persistent virus infection in post-natal life was stunting in viraemic animals. It was also shown that a congenitally infected pig shed virus for 2.5 years and in sufficient quantity to infect other pigs, even by indirect contact. Unlike ruminants, congenitally infected pigs sometimes had persistent viraemia but eventually eliminated the virus. Clearance of virus from the blood was related to the appearance of neutralizing antibodies. However, clearance from the tissues sometimes took as much as 5 months longer than from the blood.  相似文献   
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