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471.
TV Perneger JF Etter MA Raetzo P Schaller H Stalder 《Canadian Metallurgical Quarterly》1996,50(4):463-468
OBJECTIVES: To measure satisfaction with medical visits in various health care settings and to assess the extent to which differences in satisfaction scores between health care settings can be attributed to patients' characteristics. DESIGN: This was a cross sectional survey to measure seven dimensions of patient satisfaction. SETTINGS: Ambulatory visits to 'gatekeepers' or specialists in a newly established managed care organisation, a private group practice, or a university hospital outpatient clinic in Geneva, Switzerland. PATIENTS: There were altogether 1027 adult patients (81% participation rate). RESULTS: Patients who consulted physicians in the private group practice reported higher levels of satisfaction (overall mean 83.2 on a scale between 0 and 100) than university clinic patients (79.7), patients of independent specialists within the managed plan (78.5), and patients of managed plan gatekeepers (69.8, intergroup differences p < 0.001). Differences between settings were reduced after adjustment for sex, age, country of origin, general practitioner versus specialist visit, and scheduled versus urgent visit (adjusted scores: 80.8, 78.8, 77.6, and 72.7 in the four settings, p < 0.001). Intergroup differences were largest for general satisfaction, but small and non-significant for satisfaction with explanations given by the physician and for time spent with the patient. CONCLUSIONS: Patient satisfaction varied widely between health care settings. Differences in satisfaction ratings could be ascribed only partly to disparities in patient populations. Patients of managed plan gatekeepers were least satisfied, presumably because they could not choose their physician freely. Comparison of patient satisfaction across health care settings can provide a basis for targeted quality improvement initiatives. 相似文献
472.
We present psychological experiments that reveal two motion systems, a specific and an unspecific one. The specific system prevails at medium to high temporal frequencies. It comprises at least two separate motion pathways that are selective for color and for luminance and that do not interact until after the motion signal is extracted separately in each. By contrast, the unspecific system prevails at low temporal frequencies and it combines color and luminance signals at an earlier stage, before motion extraction. The successful implementation of an efficient and accurate technique for assessing equiluminance corroborates further the main findings. These results offer a general framework for understanding the nature of interactions between color and luminance signals in motion perception and suggest that previously proposed dichotomies in motion processing may be encompassed by the specific/unspecific dichotomy proposed here. 相似文献
473.
474.
EE Maksimova LIu Popova TV Kargatova VV Shpagina 《Canadian Metallurgical Quarterly》1997,66(2):223-227
Authors compare two methods of hearing assessment using ABR recordings in children at the age of 1 to 6 years. Following are the applied methods: 1) ABR recording in natural sleep at night and 2) ABR recording in pharmacologically induced sleep. Advantages and disadvantages of the methods are presented and parameters such as: time of examination, number of averages, number of artefacts and percentage of successful recordings have been evaluated. 相似文献
475.
本文介绍一种既能起表面活性剂作用,又具有抗磨、抗蚀、润滑性能的新型水溶性有机金属防锈添加剂12-丁酰基蓖麻油酸的合成方法及性能的测试. 相似文献
476.
477.
SJ Lin RA Pufahl A Dancis TV O'Halloran VC Culotta 《Canadian Metallurgical Quarterly》1997,272(14):9215-9220
The ATX1 gene of Saccharomyces cerevisiae was originally identified as a multi-copy suppressor of oxidative damage in yeast lacking superoxide dismutase. We now provide evidence that Atx1p helps deliver copper to the copper requiring oxidase Fet3p involved in iron uptake. atx1Delta null mutants are iron-deficient and are defective in the high affinity uptake of iron. These defects due to ATX1 inactivation are rescued by copper treatment, and the same has been reported for strains lacking either the cell surface copper transporter, Ctr1p, or the putative copper transporter in the secretory pathway, Ccc2p. Atx1p localizes to the cytosol, and our studies indicate that it functions as a carrier for copper that delivers the metal from the cell surface Ctr1p to Ccc2p and then to Fet3p within the secretory pathway. The iron deficiency of atx1 mutants is augmented by mutations in END3 blocking endocytosis, suggesting that a parallel pathway for intracellular copper trafficking is mediated by endocytosis. As additional evidence for the role of Atx1p in iron metabolism, we find that the gene is induced by the same iron-sensing trans-activator, Aft1p, that regulates CCC2 and FET3. 相似文献
478.
Malignant hyperthermia (MH) and central core disease (CCD) mutations were introduced into full-length rabbit Ca2+ release channel (RYR1) cDNA, which was then expressed transiently in HEK-293 cells. Resting Ca2+ concentrations were higher in HEK-293 cells expressing homotetrameric CCD mutant RyR1 than in cells expressing homotetrameric MH mutant RyR1. Cells expressing homotetrameric CCD or MH mutant RyR1 exhibited lower maximal peak amplitudes of caffeine-induced Ca2+ release than cells expressing wild type RyR1, suggesting that MH and CCD mutants might be "leaky." In cells expressing homotetrameric wild type or mutant RyR1, the amplitude of 10 mM caffeine-induced Ca2+ release was correlated significantly with the amplitude of carbachol- or thapsigargin-induced Ca2+ release, indicating that maximal drug-induced Ca2+ release depends on the size of the endoplasmic reticulum Ca2+ store. The content of endogenous sarco(endo)plasmic reticulum Ca2+-ATPase isoform 2b (SERCA2b), measured by enzyme-linked immunosorbent assay, 45Ca2+ uptake, and confocal microscopy, was increased in HEK-293 cells expressing wild type or mutant RyR1, supporting the view that endoplasmic reticulum Ca2+ storage capacity is increased as a compensatory response to an enhanced Ca2+ leak. When heterotetrameric (1:1) combinations of MH/CCD mutant and wild type RyR1 were expressed together with SERCA1 to enhance Ca2+ reuptake, the amplitude of Ca2+ release in response to low concentrations of caffeine and halothane was higher than that observed in cells expressing wild type RyR1 and SERCA1. In Ca2+-free medium, MH/CCD mutants were more sensitive to caffeine than wild type RyR1, indicating that caffeine hypersensitivity observed with a variety of MH/CCD mutant RyR1 proteins is not dependent on extracellular Ca2+ concentration. 相似文献
479.
TV Roshini Ranjith V Ravi A Reema Mathew Anoop Balakrishnan Kadan Perumal Sankar Subbian 《International journal of imaging systems and technology》2020,30(4):1173-1193
The most effective treatment for diabetic retinopathy (DR) is the early detection through regular screening, which is critical for a better prognosis. Automatic screening of the images would assist the physicians in diagnosing the condition of patients easily and accurately. This condition searches out for special importance of image processing technology in the way of processing the retinal fundus images. Accordingly, this article plans to develop an automatic DR detection model with the aid of three main stages like (a) image preprocessing, (b) blood vessel segmentation, and (c) classification. The preprocessing phase includes two steps: conversion of RGB to Lab, and contrast enhancement. The Histogram equalization process is done using the contrast enhancement of an image. To the next of preprocessing, the segmentation phase starts with a valuable procedure. It includes (a), thresholding the contrast-enhanced and filtered images, (b) thresholding the keypoints of contrast-enhanced and filtered images, and (c) adding both thresholded binary images. Here, the filtering process is performed by proposed adaptive average filtering, where the filter coefficients are tuned or optimized by an improved meta-heuristic algorithm called fitness probability-based CSO (FP-CSO). Finally, the classification part uses Deep CNN, where the improvement is exploited on the convolutional layer, which is optimized by the same improved FP-CSO. Since the conventional CSO depends on a fitness probability in the improved algorithm, the proposed algorithm termed as FP-CSO. Finally, valuable comparative and performance analysis has confirmed the effectiveness of the proposed model. 相似文献
480.
Aram Galstyan 《Autonomous Agents and Multi-Agent Systems》2013,26(1):37-53
The problem of multi-agent learning and adaptation has attracted a great deal of attention in recent years. It has been suggested that the dynamics of multi agent learning can be studied using replicator equations from population biology. Most existing studies so far have been limited to discrete strategy spaces with a small number of available actions. In many cases, however, the choices available to agents are better characterized by continuous spectra. This paper suggests a generalization of the replicator framework that allows to study the adaptive dynamics of Q-learning agents with continuous strategy spaces. Instead of probability vectors, agents’ strategies are now characterized by probability measures over continuous variables. As a result, the ordinary differential equations for the discrete case are replaced by a system of coupled integral-differential replicator equations that describe the mutual evolution of individual agent strategies. We derive a set of functional equations describing the steady state of the replicator dynamics, examine their solutions for several two-player games, and confirm our analytical results using simulations. 相似文献