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Problems that can occur when single implants are utilized to restore first molar teeth include the frequent loosening of screws, as well as screws and/or implant breakage. These may result from torquing and rotational movements of the prosthesis during masticatory and parafunctional mandibular movements. When sufficient bone and mesio-distal restorative space is present, the placement of two implants should be considered.  相似文献   
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Statement of problem. Controversy surrounds the use of hydrofluoric acid to prepare precementation surfaces of indirect composites.Purpose. This study was conducted to compare effects of combining hydrofluoric or orthophosphoric acid with microetching as precementation treatments.Material and methods. Nine specimens of three composite materials were prepared to simulate heat-cured indirect restorations. The specimen surfaces were prepared with one of three treatments. Adhesive Bond II and Twinlook cements were used to bond a phosphoric acid-etched disk of P50 to the treated surface. Analysis of variance and Scheffé tests were used to assess the bond strength data. Scanning electron microscopy and microscopic analysis of the fractured and treated surfaces were also performed.Results. Bond strengths for all surface treatments did not significantly differ. Hybrids had a higher bond strength with etching than microfills, and mechanical roughening produced the greatest bond strengths with microfills. Microetching with orthophosphoric acid produced higher bond strengths than microetching with hydrofluoric acid on hybrids.Conclusions. Acid etching alone is not sufficient to produce effective bond strengths, and hydrofluoric acid treatments are detrimental to the resin composite. (J Prosthet Dent 1997;77:568-72.)  相似文献   
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Aseptic peritonitis was induced in rabbits by intraperitoneal injection of irritating agents, mainly starch suspensions. The inflammatory response was followed in the peritoneal lavage fluid by cell counts (average increase about 800-fold the first day) and hyaluronan concentration (average increase about 200-fold on the second and third days). The turnover rate of hyaluronan was studied by injecting tritium-labeled hyaluronan intraperitoneally and by following the appearance of tritiated water in serum. In control animals given trace amounts of hyaluronan, half-lives of 1–14 h were recorded. When the labeled polysaccharide had been mixed with 10 mg/ml of unlabeled hyaluronan, the half-life was approximately one day. Rabbits with ongoing peritonitis exhibited half-lives between 1 and 16 h. It was concluded that there was a large individual variation in uptake kinetics, that the removal process could be receptor mediated, and that the increase in intraperitoneal hyaluronan in peritonitis mainly was due to an increased production of the polysaccharide rather than a decreased rate of removal.  相似文献   
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Prevention Science - The impact of evidence-based parenting health promotion programs is threatened by limited enrollment and attendance. We used a discrete choice experiment (DCE) to examine how...  相似文献   
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Statins are a class of lipid-lowering medications used worldwide by millions of people and are safe for frequent use in most patients. However, they cause necrotizing autoimmune myopathy in some patients. We reviewed case reports of 80 patients from 2010 to present diagnosed with statin-induced necrotizing autoimmune myopathy (SINAM), aiming to analyze the clinical, physiological, serologic characteristics and outcomes of SINAM. The mean age of these patients was 66 ±9.4, the majority being male (61.3%). All patients reported proximal muscle weakness, and a few had myalgias, extra muscular symptoms such as dysphagia, and pulmonary complications. Most of the patients were on atorvastatin, simvastatin, or rosuvastatin. The mean creatine kinase was 10,094.2 ±7,351.7 U/l, and anti-3-hydroxy-3-methylglutaryl-coenzyme A reductase enzyme was positive for 93.8% of patients. The majority of patients were started on steroids; other treatments were also used. Prompt cessation of statins and initiation of immunosuppressants reduced morbidity and mortality.  相似文献   
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RAD51 is an ATP-dependent recombinase, recruited by BRCA2 to mediate DNA double-strand breaks repair through homologous recombination and represents an attractive cancer drug target. Herein, we applied for the first-time protein-templated dynamic combinatorial chemistry on RAD51 as a hit identification strategy. Upon design of N-acylhydrazone-based dynamic combinatorial libraries, RAD51 showed a clear templating effect, amplifying 19 N-acylhydrazones. Screening against the RAD51–BRCA2 protein–protein interaction via ELISA assay afforded 10 inhibitors in the micromolar range. Further 19F NMR experiments revealed that 7 could bind RAD51 and be displaced by BRC4, suggesting an interaction in the same binding pocket of BRCA2. These results proved not only that ptDCC could be successfully applied on full-length oligomeric RAD51, but also that it could address the need of alternative strategies toward the identification of small-molecule PPI inhibitors.  相似文献   
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