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991.
The purpose of this pilot study was to refine and evaluate methods of measuring costs of an innovative home-health nursing intervention designed to support frail, older persons and their family caregivers. We evaluated a multifaceted strategy to collect a detailed utilization profile from 22 caregiver/care receiver dyads for hospital, ambulatory, home health, nursing home, and community services. The strategy was feasible for most participants, maximized accuracy of cost data, and minimized research burden on study participants. Lower overall costs were found in the intervention group, but the difference was not significant. Approaches to the measurement of costs in this study can serve as models for evaluating other innovations in nursing, home care, and long-term care.  相似文献   
992.
993.
The glycoxidation products Nepsilon-(carboxymethyl)lysine and pentosidine increase in skin collagen with age and at an accelerated rate in diabetes. Their age-adjusted concentrations in skin collagen are correlated with the severity of diabetic complications. To determine the relative roles of increased glycation and/or oxidation in the accelerated formation of glycoxidation products in diabetes, we measured levels of amino acid oxidation products, distinct from glycoxidative modifications of amino acids, as independent indicators of oxidative stress and damage to collagen in aging and diabetes. We show that ortho-tyrosine and methionine sulfoxide are formed in concert with Nepsilon-(carboxymethyl)lysine and pentosidine during glycoxidation of collagen in vitro, and that they also increase with age in human skin collagen. The age-adjusted levels of these oxidized amino acids in collagen was the same in diabetic and nondiabetic subjects, arguing that diabetes per se does not cause an increase in oxidative stress or damage to extracellular matrix proteins. These results provide evidence for an age-dependent increase in oxidative damage to collagen and support previous conclusions that the increase in glycoxidation products in skin collagen in diabetes can be explained by the increase in glycemia alone, without invoking a generalized, diabetes-dependent increase in oxidative stress.  相似文献   
994.
Human papillomavirus (HPV) infection with potentially oncogenic types 16 or 18 is common in genital lesions especially in uterine carcinomas. In such lesions, in situ hybridization with non-radioactive probes is a powerful tool for the histopathologist to detect and type HPV DNA either on cell deposits or on tissue sections. The use of an immunohistochemical method involving alkaline phosphatase and Fast Red TR salt/naphthol AS-MX phosphate is proposed for use with conventional bright-field or fluorescence microscopy as well as by laser scanning confocal microscopy. The alkaline phosphatase-Fast Red reaction has the advantage of producing a red precipitate that permits the detection of in situ hybridization signals by bright-field microscopy, and of obtaining a strong red fluorescence characterized by a lack of bleaching when excited by a green light. Therefore, the alkaline phosphatase-Fast Red reaction is well adapted for observations by fluorescence and confocal microscopy, the latter method allowing the detection, in tissue sections of cervical intraepithelial lesions, of small punctate and large diffuse hybridization signals, considered as integrated and episomal states of HPV DNA respectively. The combination of in situ hybridization with the alkaline phosphatase-Fast Red reaction and confocal microscopy is particularly convincing when hybridization signals are of small size and/or of low fluorescence intensity, especially if they are present in various focal planes; in such conditions, infected cells are easily detected by three-dimensional reconstruction. Therefore, this combination is a suitable method for identifying and characterizing HPV DNA in cells and tissue sections.  相似文献   
995.
Endothelin-1 (ET-1) is the most potent vasoconstrictor known to date, and it was proposed that this peptide plays a major role in myocardial ischemia/reperfusion injury. ET-1 could increase myocardial susceptibility to ischemia by two mechanisms: via coronary flow reduction and/or via direct, metabolic effects on the heart. In isolated, buffer-perfused rat hearts, function was measured with a left ventricular balloon, and energy metabolism (ATP, phosphocreatine, inorganic phosphate, intracellular pH) was estimated by 31NMR-spectroscopy. Under constant pressure perfusion, hearts were subjected to 15 min of control perfusion, 15 ("moderate injury") or 30 ("severe injury") min of global ischemia, followed by 30 min of reperfusion. Hearts were pre-treated with ET-1 (boluses of 0.04, 4, 40 of 400 pmol) 5 min prior to ischemia. In the control period, ET-1 reduced coronary flow, ventricular function, phosphocreatine and intracellular pH dose-dependently: during ischemia/reperfusion, coronary flow, functional recovery and high-energy phosphate metabolism were adversely affected by ET-1 in a dose-related manner. To study effects of ET-1 not related to coronary flow reduction, additional hearts were perfused under constant flow conditions (ET-1 0 or 400 pmol) during 15 min of control, 15 min of ischemia and 30 min of reperfusion. When coronary flow was held constant, functional and energetic parameters were similar for untreated and ET-1 treated hearts during the entire protocol, i.e. the adverse effects of ET-1 on function and energy metabolism during ischemia/reperfusion were completely abolished. In both constant pressure and constant flow protocols, 400 pmol ET-1 reduced the extent of ischemic intracellular acidosis. The authors conclude that ET-1 increases the susceptibility of isolated hearts to ischemia/reperfusion injury via reduction of coronary flow.  相似文献   
996.
MC Ryan 《Canadian Metallurgical Quarterly》1998,24(3):19-27; quiz 50-1
To determine the effects of preexisting levels of loneliness and social support on cognitive decline during hospitalization, 145 elderly subjects 65 to 92 years old without impaired cognition were tested for levels of loneliness, social support, and cognitive status on admission to an acute care hospital. Five days later, cognitive status was again measured in the remaining 86 patients. Loneliness was found to be inversely related to cognitive status on admission. In those with high loneliness scores on admission, cognitive status had improved significantly 5 days later. High social support was correlated with high cognitive status on admission and significant cognitive decline during hospitalization.  相似文献   
997.
UV-irradiated human fibroblasts in tissue culture were exposed to photoreactivating light in an attempt to demonstrate a light-dependent loss of thymine dimers from the acid-insoluble fraction of the DNA. The only experimental conditions in which this phenomenon was observed was if the cells were grown for at least 10 days in Dulbecco's modified Eagle's minimum essential medium. Such cells lost a maximum of between 10-30% of the thymine dimers from their DNA during illumination for 1 h. When cells were grown in a variety of other media the phenomenon was not observed. The present experiments do not discriminate between true enzymatic photoreactivation and a medium dependent photosensitization phenomenon that is not enzymatic in nature.  相似文献   
998.
An overview on the literature on primary open angle glaucoma that has appeared in the optometric and ophthalmological journals during the past ten years indicates a continuing reevaluation, and perhaps at times a seeming disagreement, regarding the parameters of this disease. Opinions have varied, and still do, on such matters as to whether or not the diagnosis of glaucoma is contingent upon a field defect, the existence of low tension glaucoma, the ramifications of ocular hypertension, what constitutes a glaucomatous appearance of the disc, field defects versus the appearance of the disc, field defects versus the appearance of the disc, and what constitutes an early glaucomatous field defect. Voices have been raised in some quarters that claim that waiting for a field defect to develop may not be in the best interest of the patient, and that the glaucoma suspect should be identified as early as possible. Treatment before the development of a field defect is enjoying support from some glaucoma authorities. Good clinical practice will permit the conscientious optometrist to identify those patients who have very early signs of this disease.  相似文献   
999.
The present study demonstrates that a 2 hr period of sustained hypoxia results in a focally destructive process, a process which resolves by 5 days. That the changes described in earlier work are not overwhelming to the animal suggest that an early, focal, and reversible stage of the development of acute enterocolitis in the puppy can be described with the aid of electron microsocpy.  相似文献   
1000.
This report describes several methods of degrading imagery through the central portion of a spectacle lens to provide a cosmetically acceptable means of obtaining single vision in the central field of patients with intractable diplopia. For 2 strabismic patients with annoying diplopia, we applied to 1 spectacle lens a centrally placed disc (about 1 inch diameter) consisting of (1) translucent tap,a (2) a +7 D Fresnel lens,b or (3) stippled, clear lacquer. For 1 patient, the lacquer was the most acceptable; for the other, the tape was best. We present here the case reports for these 2 patients, showing why they preferred different image-degrading methods and how these and other methods of central-field image degrading can be advantageous even when diplopia is present across most of the visual field.  相似文献   
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