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141.
The focus of this article is on elderly patients' and nursing staff perceptions of informed consent in the care of elderly patients/residents in five European countries. The results suggest that patients and nurses differ in their views on how informed consent is implemented. Among elderly patients the highest frequency for securing informed consent was reported in Finland; the lowest was in Germany. In contrast, among nurses, the highest frequency was reported in the UK (Scotland) and the lowest in Finland. In a comparison of patients' and nurses' perceptions, nurses had more positive views than patients in all countries except Finland. Patients with less need for nursing interventions in Greece and Spain gave their consent less often. The German and Greek patients were older, and the results also point to an association between this and their lower frequency of giving consent. In Spain, patients who were married or who had a family member or friend to look after their personal affairs were more likely to be included in the group whose consent was sought less often. This is the fourth of a set of five articles published together in this issue of Nursing Ethics in which the results of this comparative research project are presented.  相似文献   
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Cells of the reticuloendothelial system (RES e.g. macrophages) play an important role in the immunopathogenesis of AIDS. The objective of the present study was to investigate the possibility of specifically targeting antiviral drugs such as azidothymidine (AZT) to macrophages using nanoparticles as colloidal drug carriers. In a first series of experiments the body distribution of –labelled AZT bound to nanoparticles and a similarly prepared control solution with unbound AZT were studied in rats after intravenous injection. In a second series of experiments polysorbate 80-coated nanoparticles and a solution of AZT in saline were tested. –labelled AZT was bound to nanoparticles using the surfactant bis(2-ethylhexyl) sulphosuccinate sodium (DOSS). The radioactivity in several organs, including those containing large numbers of macrophages, was measured after intravenous injection of the AZT-nanoparticles and the AZT-control solutions. AZT concentrations were up to 18 times higher in organs belonging to the RES if the drug was bound to nanoparticles compared with unbound AZT. These results demonstrate that nanoparticles are a potential drug targeting system for anti-AIDS drugs. The increase in drug concentration at the sites containing abundant macrophages may allow a reduction in dosage to reduce systemic toxicity.  相似文献   
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Flumazenil, a new and specific benzodiazepine antagonist that appears to be free of intrinsic pharmacologic action, is extensively metabolized by oxidative processes and represents a high-clearance drug. Consequently, it could be anticipated that hepatic disease affects the elimination and oral bioavailability of flumazenil. Therefore, the pharmacokinetics of flumazenil was evaluated in eight patients who had moderate cirrhosis and in eight age-matched healthy volunteers after a single oral dose (30 mg) and after an intravenous dose (2 mg). The mean half-life (t1/2) was 0.8 versus 1.4 hours (p = 0.003) and total plasma clearance was 1201 versus 705 ml per minute (p = 0.009) for control subjects versus patients with cirrhosis. Bioavailability increased from the normal 28% to 65% (p = 0.001) in patients with hepatic dysfunction. Routine liver tests did not correlate with the elimination of flumazenil in individual patients. It can be concluded that elimination of flumazenil is impaired in patients who have stable alcoholic cirrhosis. Despite the relative wide margin of safety of flumazenil, somewhat lower doses could be effective in such patients if long-term oral use is anticipated.  相似文献   
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In vivo instruction of suppressor commitment in naive T cells   总被引:31,自引:0,他引:31       下载免费PDF全文
The induction of antigen-specific tolerance in the mature immune system of the intact organism has met with limited success. Therefore, nonspecific immunosuppression has been the treatment of choice to prevent unwanted immunity. Here, it is shown that prolonged subcutaneous infusion of low doses of peptide by means of osmotic pumps transforms mature T cells into CD4+25+ suppressor cells that can persist for long periods of time in the absence of antigen and confer specific immunologic tolerance upon challenge with antigen. The described procedure resembles approaches of tolerance induction used decades ago, induces tolerance in the absence of immunity, and holds the promise to become an effective means of inducing antigen-specific tolerance prospectively, whereas its power to suppress already ongoing immune responses remains to be determined.  相似文献   
146.
The retina of the weakly electric fish Gnathonemus petersii is a so‐called grouped retina where photoreceptors are bundled. These bundles are regarded as functional units and this type of retinal specialization is uniquely found in teleosts. To understand how this anatomical organization influences visual information processing we investigated the morphology and distribution of retinal ganglion cells (GCs) and the response properties of retinal afferents terminating in the major retinorecipient area, the optic tectum. GCs were classified based on their dendritic morphology (dendritic field diameters <90–100 μm: narrow‐field GCs; 110–280 μm: widefield GCs; >280 μm: giant GCs). Within these classes subtypes were distinguished based on the ramification patterns of the dendrites in the sublaminae of the inner plexiform layer. Properties of presumed optic nerve terminals were investigated in the optic tectum using extracellular recordings. Physiological classes could be observed based on their response to visual stimuli (on; off; on‐off, and fast units). Receptive field sizes and spatiotemporal properties were classified and the topographical representation of the visual space was mapped in the tectum. Gratings of low spatial frequencies were best responded to and followed up to high temporal frequencies (>30 Hz). Most of the recorded units were directionally selective. No evidence of distorted topographies in the tectum was found, i.e., no overrepresentation of the retina was seen in the tectum opticum. The grouped retina of G. petersii seems to be optimized for the detection of large, fast objects in an environment of low optical quality. J. Comp. Neurol. 521:4075–4093, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
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Evaluation of the hemoglobin A1c-analyzer TOSOH HLC-723 G7   总被引:1,自引:0,他引:1  
The TOSOH HLC-723 G7 is a compact analyzer designed for the measurement of HbA1c under routine laboratory conditions. The analyzer has an automatic blood tube supply and positive sample identification. Samples are transported automatically via racks in a continuous-load mode, cap piercing is optional. Tests devoted to the assessment of reproducibility and accuracy of analytical results indicated that over a test period of 17 days, the intra-assay variation (CV) was 1.79%, and the inter-assay variation 2.60%, respectively. A comparison with the predecessor model G5 showed a very good correlation (r = 0.997, y = 1.0041x - 0.00172; n = 149). The presence of high triglyceride, bilirubin or urea concentrations in patient samples did not influence the analytical precision. The labile HbA1c fraction (L-A1c) is clearly separated during chromatography and thus does not compromise HbA1c analysis. With a protocol of 1.2 minutes, the TOSOH G7 is a very fast analyzer, designed for laboratories with a high throughput of samples.  相似文献   
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