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121.
Phonetics, esthetics, function, and comfort form the foundation of a successful dental prosthesis. A review of the mechanics of speech as well as common speech problems encountered with a removable maxillary prosthesis are presented. The use of a palatogram to aid the clinician in the assessment and resolution of speech problems associated with a maxillary denture is demonstrated.  相似文献   
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用液体闪烁计数法测定离体再灌注兔心肌线粒体内45Ca2+的放射性强度.观察三磷酸腺苷-氯化镁冷稀释血停搏液和冷稀释血停搏液对缺血再灌注兔心肌线粒体内45Ca2+的影响.结果表明,在30min以内使用冷稀释血停搏液组兔心肌线粒体内45Ca2+放射性强度高于三磷酸腺苷-氯化镁冷稀释血停搏液组(P<0.05),而60min时冷稀释血停搏液组的放射性强度稍高或接近于三磷酸腺苷-氯化镁冷稀释血停搏液组,差异无显著性(P>0.05).在27例心内直视手术中使用三磷酸腺苷-氯化镁冷稀释血停搏液均获良好效果.  相似文献   
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We investigated the importance of prostaglandin E2 (PGE2) release in interleukin-1 (IL-1)-induced inhibition of aggrecan synthesis by chondrocytes. Keratan sulfate (KS) production was measured in parallel with PGE2 release in chondrocytes. IL-1 inhibited KS production and stimulated PGE2 release. In the presence of PGE2, there was a dosedependent decrease in baseline KS production. Indomethacin and dexamethasone partially blocked the IL-1-induced PGE2 release while KS production recovered. Our results suggest that IL-1 inhibits KS production, in part, by stimulating the release of PGE2.  相似文献   
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Islet transplants for large numbers of patients with diabetes will require xenografts. Microencapsulation is an appealing method for islet xenografting. However, graft function has been limited by a cellular reaction, particularly intense in spontaneously diabetic, NOD mice. The purpose of this study was to elucidate the mechanism of this reaction. Poly-1-lysine-alginate microcapsules containing 4000-12,000 dog or 1800-2000 rat islets were xenografted intraperitoneally into streptozotocin (SZN)-diabetic C57BL/6J and NOD mice, with or without recipient treatment with GK 1.5 (anti-CD4 monoclonal antibody) (20-30 microliters i.p. every 5 days, begun on day -7. Grafts were considered technically successful if random blood glucose (BG) was normalized (less than 150 mg/dl) within 36 hr. Graft failure was defined as BG greater than 250 mg/dl. Dog and rat islets in microcapsules normalized BG in both SZN and NOD mice within 24 hr routinely. Empty microcapsules and GK 1.5 treatments alone did not affect BG. NODs destroyed both microencapsulated dog and rat islets more rapidly than did SZN-diabetic mice (P less than .01). Graft biopsies showed an intense cellular reaction, composed of lymphocytes, macrophages and giant cells, and no viable islets. GK 1.5 treatment significantly prolonged both dog-to-NOD and rat-to-NOD grafts (P less than 0.01). Biopsies of long-term functioning grafts (on days 65-85) demonstrated viable islets and no cellular reaction around microcapsules; 1/4 rat and 1/8 dog islet xenografts continued to function indefinitely in NOD recipients, even after cessation of GK 1.5 therapy. Prediabetic NODs receiving encapsulated dog or rat islets mounted a moderate cellular reaction to grafts. Empty microcapsules excited no cellular reaction in diabetic or prediabetic NODs. We conclude that the NOD reaction to microencapsulated xenogeneic islets is helper T cell-dependent, and that the target of this reaction is not the microcapsule itself, but the donor cells within.  相似文献   
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The Child and Adolescent Trial for Cardiovascular Health (CATCH) is a multisite intervention research study that builds on significant progress made in school health education research in the 1980s. The study has three phases: Phase I deals with study design, intervention, and measurement development, Phase II involves the main trial in 96 schools in four states, and Phase III focuses on analysis. The intervention program targets third-fifth grade students and focuses on multiple cardiovascular health behaviors, including eating habits, physical activity, and cigarette smoking. Classroom curricula, school environmental change, and family involvement programs are developed for each grade level and behavioral focus. This paper describes Phase II of CATCH with a rationale for cardiovascular health promotion with youth. The process of change that appears to be necessary for school-based health promotion and that will be tested in CATCH are presented as a framework to guide these efforts.  相似文献   
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