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The development and long-term fate of the inner cellular lining in 72 small caliber (3 mm inner diameter) fibrous polyurethane vascular prostheses explanted from dog carotid and/or femoral arteries at times ranging from 1.5 weeks up to 53 months after implantation were studied by scanning electron and light microscopy. A continuous cellular ingrowth from the vascular stumps into the 3 cm long prostheses was observed, which eventually resulted in a complete cellular lining 6 months after implantation. No other ways of endothelialization were noted. In fully endothelialized prostheses, the cellular ingrowth extended approximately 8 mm into the prostheses and consisted of several layers of fibroblasts and smooth muscle cells, covered by a very thin endothelioid cell layer. The newly developed lining was firmly anchored onto the inner prosthetic surface by means of cellular protrusions extended into the fibrous texture of the prosthetic wall. It was concluded that under experimental conditions in the dog complete endothelialization can be obtained in fibrous polyurethane vascular prostheses and that the lining remained thin and stable throughout the observation period of 53 months after implantation.  相似文献   
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An interactive course in drug information skills developed for pharmacists at a not-for-profit, tertiary-care hospital is described. Faculty members from the area school of pharmacy developed, taught, and evaluated the program. Before the course was developed, pharmacy staff members were asked to rate their drug information skills; the pharmacists' responses indicated their belief that they were not proficient enough in the skills needed in daily practice. The course content and format were refined after 11 pharmacists completed a pilot program. A handbook was developed that contained objectives, session outlines, and literature for each of the six topics chosen for the course. Although the handbook was the primary teaching aid, wall charts and computer demonstrations were also used. Sessions were structured for the needs of adult students by using a small-group discussion format that emphasized the practical relevance of the information and encouraged participants to share personal experiences. Each session was offered on two separate days to facilitate attendance. Those who completed the course received credit for 12 contact hours of continuing education. Of 16 pharmacists enrolled in the course, 11 completed it. An interactive course in drug information skills, developed to meet the needs of hospital pharmacists, was well accepted because it incorporated personal experiences, small-group activities, and flexible scheduling.  相似文献   
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采用间接ELISA检测23名肾移植受者血清巨细胞病毒(CMV)抗体,共检出18名(78%)活动性CMV感染,其中10名(44%)为原发性感染。结果证实CMV-IgE和-IgA具有较好的血清学诊断价值,优于CMV-IgM。  相似文献   
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The beta-amyloid (Abeta) precursor protein (APP) is cleaved sequentially by beta-site of APP-cleaving enzyme (BACE) and gamma-secretase to release the Abeta peptides that accumulate in plaques in Alzheimer's disease (AD). GGA1, a member of the Golgi-localized gamma-ear-containing ARF-binding (GGA) protein family, interacts with BACE and influences its subcellular distribution. We now report that overexpression of GGA1 in cells increased the APP C-terminal fragment resulting from beta-cleavage but surprisingly reduced Abeta. GGA1 confined APP to the Golgi, in which fluorescence resonance energy transfer analyses suggest that the proteins come into close proximity. GGA1 blunted only APP but not notch intracellular domain release. These results suggest that GGA1 prevented APP beta-cleavage products from becoming substrates for gamma-secretase. Direct binding of GGA1 to BACE was not required for these effects, but the integrity of the GAT (GGA1 and TOM) domain of GGA1 was. GGA1 may act as a specific spatial switch influencing APP trafficking and processing, so that APP-GGA1 interactions may have pathophysiological relevance in AD.  相似文献   
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Prospective study of the evolution of Raynaud's phenomenon   总被引:2,自引:0,他引:2  
Seventy-four patients with Raynaud's phenomenon and no associated illness were followed prospectively to determine whether a secondary disease would develop, and clinical and laboratory assessments were performed at study entry to determine their association with the subsequent development of disease. After an average of 2.7 years of follow-up (range 0.5 to 5.7 years), outcome information was available on 58 persons (78.4 percent). A connective tissue disease developed in 11 (19.0 percent): three systemic sclerosis and eight CREST syndrome. The two variables at entry most strongly associated with the subsequent development of a connective tissue disease were an abnormal nailfold capillary pattern (adjusted odds ratio = 26.82, 95 percent confidence interval = 4.69, 153.2) and an abnormal pulmonary function test result (odds ratio = 4.78, 95 percent confidence interval = 1.02, 22.41). The positive association of an abnormal barium esophagram, presence of antinuclear antibodies, and cutaneous abnormalities did not reach statistical significance. The development of connective tissue diseases in this group of patients is not rare. An abnormal nailfold capillary pattern is strongly associated with the subsequent development of systemic sclerosis or CREST syndrome in patients with Raynaud's phenomenon.  相似文献   
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