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991.
The authors examine the role and nature of the market for voluntary health insurance in the European Union and review the impact of public policy, at both the national and E.U. levels, on the development of this market in recent years. The conceptual framework, based on a model of industrial analysis, allows a wide range of policy questions regarding market structure, conduct, and performance. By analyzing these three aspects of the market for voluntary health insurance, the authors are also able to raise questions about the equity and efficiency of voluntary health insurance as a means of funding health care in the European Union. The analysis suggests that the market for voluntary health insurance in the European Union suffers from significant information failures that seriously limit its potential for competition or efficiency and also reduce equity. Substantial deregulation of the E.U. market for voluntary health insurance has stripped regulatory bodies of their power to protect consumers and poses interesting challenges for national regulators, particularly if the market is to expand in the future. In a deregulated environment, it is questionable whether this method of funding health care will encourage a more efficient and equitable allocation of resources.  相似文献   
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Background: Glucagon‐like peptide–2 (GLP‐2) enhances intestinal absorption in adult animals. Glucocorticosteroids accelerate the ontogeny of the intestine and increase sugar uptake in adult animals. Modifying the maternal diet during lactation alters nutrient uptake in the offspring. The authors hypothesized that GLP‐2 and dexamethasone, when administrated to lactating rat dams, enhance sugar uptake in the suckling and postweanling offspring. Methods: Rat dams were treated during lactation with GLP‐2 (0.1 μg/g/day subcutaneously [SC], twice daily), dexamethasone (0.128 μg/g/day SC, once daily), GLP‐2 + dexamethasone (same doses), or placebo. The suckling offspring were sacrificed at 19–21 days of age, and the postweanlings were sacrificed 4 weeks later. Intestinal glucose and fructose uptake was assessed using an in vitro ring technique. Results: GLP‐2 and dexamethasone resulted in lower body weights, and dexamethasone caused intestinal atrophy in sucklings. The jejunal atrophy in sucklings given dexamethasone was prevented by GLP‐2 + dexamethasone. In sucklings, the maximal transport rate and the Michaelis affinity constant for ileal glucose uptake were both increased by GLP‐2 and GLP‐2 + dexamethasone. In contrast, in postweanlings, the maximal transport rate for jejunal glucose uptake was reduced by dexamethasone and GLP‐2, as was ileal fructose uptake. Conclusions: Treating lactating rat dams with GLP‐2 or dexamethasone enhances glucose uptake in sucklings, but the late effect is a reduction in glucose and fructose absorption in postweanlings. The nutritional significance of these findings remains to be established.  相似文献   
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Advances in imaging technology and engineering have now permitted functional integration of a confocal endomicroscope into the distal tip of a conventional video colonoscope enabling imaging of the surface epithelium and the underlying lamina propria during ongoing video endoscopy. For the first time, the endoscopist is now able to resolve the surface and subsurface mucosa at cellular resolution in vivo and in real time. A new era in endoscopic imaging has therefore begun – histoendoscopy. In addition to providing a high-accuracy in vivo optical biopsy tool for the differentiation between benign hyperplasia, intra-epithelial neoplasia and carcinoma in sporadic cohorts, endomicroscopy with targeted biopsies has now been shown to increase the yield of intra-epithelial neoplasia complicating ulcerative colitis. Furthermore, recent data examining endomicroscopic molecular ex vivo imaging using anti-CD44v6 antibody has identified aberrant crypt foci based on their surface molecular expression. Receptor overexpression in vivo in humans may, in the near future, be exploited for the diagnosis of inflammation, neoplasia and in predicting targeted molecular therapy. Endomicroscopy will be key to this immuno-imaging interface. Within the present review, we discuss the current clinical evidence in support of confocal endomicroscopy and explore the new diagnostic possibilities for this technology.  相似文献   
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Specific immunofluorescent (IF) conjugates were prepared for Streptococcus mutans serotypes d and g. Serotype specificity was obtained by blocking the cross-reacting antibodies with soluble antigen extracted from cells of the cross-reacting strains. Soluble antigen extracts are particularly useful in obtaining specificity with quantities of conjugates that are too small to be efficiently subjected to adsorption procedures. They also can be used advantageously to block traces of cross-reactivity that frequently remain with conjugates that have been subjected to conventional adsorption procedures. S. mutans isolates from dental plaque samples were identified as belonging to serotypes d or g on the basis of IF staining with conjugates that were made type-specific by blocking the cross-reacting antibodies with appropriate soluble antigen extracts.  相似文献   
996.
Endotoxin induced disseminated intravascular coagulation in cattle   总被引:3,自引:0,他引:3  
Endotoxin administered intravenously to a group of four calves resulted in disseminated intravascular coagulation. A sublethal dose of piromen, a commercially available Pseudomonas spp endotoxin, was used. Serial measurements of total plasma fibrinogen, soluble fibrin levels, ethanol gelation tests, protamine sulfate tests, fibrinogen-fibrin-related antigen (FR-antigen) and prothrombin and thrombin times were done.Initial depression of plasma fibrinogen with a nadir of about 40% of pre-endotoxin levels at eight to 11 hours post-endotoxin (+8 to +11 hours) followed by an overcompensation to 180% at +60 to +108 hours was shown. Soluble fibrin was demonstrated in plasma from +2 to +22 hours with a peak of 100-114 mg/100 ml at +4 to +9 hours. Positive plasma ethanol gelation and protamine sulfate tests, as well as the presence of serum FR-antigen, occurred consistently following endotoxin administration. Significant increases in prothrombin times (PT) from +4 to +40 hours and in thrombin times (TT) from +4 to +16 hours were demonstrated. The peak increase of PT at +8 to +10 hours was 180%. The peak increase of TT at +6 to +9 hours was 260-290%.  相似文献   
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