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Gonadotropin-releasing hormone (GnRH) molecular variants in the brain and pituitary gland of pejerrey, Odontesthes bonariensis (Atheriniformes), were characterized by gradient reverse phase high performance liquid chromatography (RP-HPLC). Eluted fractions were tested in radioimmunoassays with different antisera. The results show that the brain extract contains three forms of GnRH: one is immunologically and chromatographically similar to cIIGnRH (chicken II), and another is similar to sGnRH (salmon). A third GnRH appears to be chromatographic and immunologically different from the nine other known forms of the vertebrate hormone. This is the only variant present in the pituitary gland.  相似文献   
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PURPOSE: To use a controlled, randomized design to assess the effect on patient satisfaction of an intensive psychosocial training program for residents. METHOD: Twenty-six first-year residents, in two internal medicine and family practice community-based programs affiliated with the Michigan State University College of Human Medicine, were randomly assigned during 1991 and 1992 to a control group or a one-month intensive training program. Experiential teaching focused on many psychosocial skills required in primary care. A 29-item questionnaire administered before and after the residents' training evaluated their patients' satisfaction regarding patient disclosure, physician empathy, confidence in physician, general satisfaction, and comparison of the physician with other physicians. Analyses of covariance with groups and gender as factors and pre-training patient satisfaction scores as the covariate evaluated the effect of the training. RESULTS: The patients of the trained residents expressed more confidence in their physicians (p = .01) and more general satisfaction (p = .02) than did the patients of controls. The effect of training on patient satisfaction with patient disclosure (p < .01) and physician empathy (p < .05) was greater for female than for male residents. CONCLUSION: The intensive psychosocial training program for residents improved their patients' satisfaction.  相似文献   
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Time-dependent thrombolytic resistance is a critical problem in thrombolytic therapy for acute myocardial infarction. Platelets have been regarded as the main source of plasminogen activator inhibitor-1 (PAI-1) found in occlusive platelet-rich clots. However, endothelial cells are also known to influence the fibrinolytic capacity of blood vessels, but their ability to actively mediate time-dependent thrombolytic resistance has not been fully established. We will show that, in vitro, tumor necrosis factor-alpha-stimulated endothelial cells secrete large amounts of PAI-1 over a period of hours, which then binds to fibrin and protects the clot from tissue plasminogen activator-induced fibrinolysis. In vivo, endothelial cells covering atherosclerotic plaques are influenced by cytokines synthesized by plaque cells. Therefore, we propose that continuous activation of endothelial cells in atherosclerotic blood vessels, followed by elevated PAI-1 secretion and storage of active PAI-1 in the fibrin matrix, leads to clot stabilization. This scenario makes endothelial cells a major factor in time-dependent thrombolytic resistance.  相似文献   
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We analyze a model of navigational map formation based on correlation-based, temporally asymmetric potentiation and depression of synapses between hippocampal place cells. We show that synaptic modification during random exploration of an environment shifts the location encoded by place cell activity in such a way that it indicates the direction from any location to a fixed target avoiding walls and other obstacles. Multiple maps to different targets can be simultaneously stored if we introduce target-dependent modulation of place cell activity. Once maps to a number of target locations in a given environment have been stored, novel maps to previously unknown target locations are automatically constructed by interpolation between existing maps.  相似文献   
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LF Cooper 《Canadian Metallurgical Quarterly》1997,18(3):271-6, 278, 280-1; quiz 282
Modern restorative dentistry is confronted with many challenges related to implant use in the craniofacial region, such as attempting to place implants in esthetically critical sites or anatomically limiting regions of the jaw. To assure a successful implant placement that is satisfactory to both the patient and the dentist, four key areas need to be improved: diagnostic procedures, surgical procedures and outcomes, esthetic results, and prosthetic complications. This article discusses how an integrated approach to these areas can improve clinical practice.  相似文献   
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