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《Current medical research and opinion》2013,29(7):462-468
SummaryAcute water diuresis and hydropenic studies were carried out in 7 healthy volunteers to investigate the site of action of a new non-sulphonamide diuretic, Bay g 2821. The effects of the drug on the concentrating and diluting mechanism, and on the renal handling of sodium, potassium, calcium, phosphorus and uric acid were studied. The results suggest sites of actions of Bay g 2821 at the proximal tubule and the medullary portion of the ascending limb of the loop ofHenle. 相似文献
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《Drug and chemical toxicology》2013,36(4):349-374
ABSTRACTEcosystems provide a wide range of services that improve human welfare. Changes in ecosystems imply potential changes in the generation of these ecosystem services and thus changes in welfare. In the lingo of economists, these welfare changes are measured as changes in economic values—increases in welfare being benefits and decreases in welfare being costs. For instance, individuals may benefit from, and thus value, reductions in risks to endangered species. Yet values for many changes in ecosystem services are not captured in market transactions, and thus measuring these values requires nonmarket valuation methods. This paper discusses ecosystem services and values from the viewpoint of an economist, explains what is meant by the valuation of ecosystems, and provides an overview of methods for valuation of ecosystem services. An example is presented from a recent natural resource damage assessment—the Green Bay total value equivalency study. Resources in the Lower Fox River and Green Bay in Wisconsin have been injured by polychlorinated biphenyl contamination from numerous paper mills along the river over several decades. The Green Bay study examines individuals' preferences and values for reducing ecosystem risks and improving ecosystem services and how these values are related to individuals' awareness of and use of ecosystem services in the area. The study uses methods from nonmarket valuation to scale potential restoration projects. 相似文献
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Blood volume following diuresis induced by furosemide 总被引:1,自引:0,他引:1
C J Schuster M H Weil J Besso M Carpio R J Henning 《The American journal of medicine》1984,76(4):585-592
Changes in blood volume were investigated following intravenous injection of a single dose of furosemide in 21 patients with pulmonary edema. In a subset of 10 patients in whom the blood urea nitrogen level was 11.4 +/- 2.2 mg/dl and the serum creatinine level was 1.3 +/- 0.1 mg/dl and in whom total urine output exceeded 1 liter over a four- to six-hour interval ("diuretic" group), no significant change in plasma or total blood volume was observed, nor were there any significant changes in hematocrit. In a "nondiuretic" group of 11 patients who had moderately decreased renal function (blood urea nitrogen level 59.3 +/- 13.0 mg/dl and serum creatinine level 2.3 +/- 0.3 mg/dl) and in whom total urine output was less than 1 liter over the four- to six-hour interval, there was a significant increase in blood volume with a concomitant decrease in hematocrit and hemoglobin levels. Furosemide-induced diuresis therefore did not deplete intravascular volume. To the contrary, actions of furosemide that were independent of its diuretic action were associated with an expansion of plasma volume in the absence of diuresis. This may be related to the venous capacitance effects of furosemide with lowering of venous resistance and, therefore, lowering of the capillary hydrostatic pressure. In addition, there was an increase in colloid osmotic pressure. Both mechanisms increase the effective oncotic pressure gradient, which favors reabsorption of extravascular (edema) fluid. It is concluded that intravascular volume was therefore replenished at a rate equal to or in excess of the volume removed by diuresis. 相似文献
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《JACC: Cardiovascular Interventions》2022,15(2):123-134
ObjectivesThe aim of this study was to assess cusp symmetry and coronary ostial eccentricity and its impact on coronary access following transcatheter aortic valve replacement (TAVR) using a patient-specific commissural alignment implantation technique.BackgroundTAVR implantation techniques to obtain neocommissural alignment have been introduced. The impact of cusp symmetry and coronary ostial eccentricity on coronary access after TAVR remains unknown.MethodsCardiac computed tomographic scans from 200 tricuspid aortic valves (TAVs) and 200 type 1 bicuspid aortic valves (BAVs) were studied. Cusp symmetry and coronary ostial eccentricity were assessed. In addition, the right coronary cusp/left coronary cusp and right coronary artery (RCA)/left coronary artery (LCA) ostia overlap views were calculated and compared.ResultsSevere cusp asymmetry (>135°) was more frequent in BAVs (52.5%) than in TAVs (2.5%) (P < 0.001), with the noncoronary cusp being the most common dominant cusp. The RCA ostium was found to be more often eccentric (>20°) than the LCA ostium (28% vs 6%, respectively; P < 0.001). Considering the right/left cusp overlap view, there was <20° deviation between the right coronary cusp–left coronary cusp centered line and the RCA-LCA centered line in 95% of all patients (TAV, 97%; BAV, 93%). The right/left cusp and coronary ostia overlap view differed by <10° and <20° fluoroscopic angulation in 75% and 98% of all cases, respectively.ConclusionsUsing the right/left cusp overlap view to obtain commissural alignment in TAVR is also an effective approach to implant one of the transcatheter heart valve commissures in the near center between both coronary ostia in most TAVs and type 1 BAVs. Preprocedural CT assessment remains crucial to assess cusp symmetry and coronary ostial eccentricity. 相似文献
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本研究观察NF-κB抑制剂Bay 11-7082对HL-60细胞Fas/FasL系统的作用及对Fas介导的HL-60细胞凋亡的影响。用RT-PCR和流式细胞术检测Bay 11-7082干预后HL-60细胞Fas、FasL和XIAP的mRNA和蛋白表达水平的变化;用ELISA方法检测Bay 11-7082干预前后sFasL水平的变化;流式细胞术检测Bay 11-7082干预前后CH-11(活性Fas抗体)诱导HL-60细胞凋亡的变化。结果表明:用Bay 11-7082干预后,HL-60细胞FasL和XIAP的mRNA和蛋白水平较对照组明显下降,差异具有显著性(p<0.05),Fas的mRNA、蛋白水平的变化和sFasL水平的变化无显著的差异(p>0.05);Bay 11-7082干预后HL-60细胞对CH-11诱导细胞凋亡敏感性显著增强。结论:Bay 11-7082可能通过下调FasL和XIAP水平增强HL-60细胞Fas介导的凋亡。 相似文献