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The ridge expansion technique using tapered osteotomes can be used anywhere in the maxilla when a change in external ridge morphology would be advantageous for both aesthetics and/or proper dental implant placement. Usually subsequent to tooth loss, the maxilla is generally somewhat undercut in form. This ridge expansion technique can be used to reduce the undercut by bulging out the base of the facial/buccal plate. This would recreate the illusion of root prominences (Figure 12) or permit implant fixtures to be inserted in a more upright position. The tapered osteotomes can therefore predictably be used to expand the buccal bone to simulate the presence of a root prominence for optimal aesthetics for placement of a fixed partial denture prosthesis (Figure 13).  相似文献   
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ObjectivesIn May 2012, United States Preventive Services Task Force (USPSTF) finalized its recommendation against prostate-specific antigen (PSA) screening in all men. We aimed to assess trends in PSA screening frequency amongst primary care physicians (PCPs) surrounding the May 2012 USPSTF recommendation.Methods and materialsThe electronic data warehouse was used to identify men aged between 40 and 79 years with no history of prostate cancer or urology visit who were evaluated by an internal medicine or family practice physician between 2007 and 2012. Analyses were directed toward PSA testing within 6-month time period from June to November, with particular focus on the 2011 (pre-USPSTF recommendation) and 2012 (post-USPSTF recommendation) cohorts. The primary outcome measure was proportion of men with at least 1 PSA test during the 6-month pre- and post-USPSTF recommendation periods.ResultsA total of 112,221 men met inclusion criteria. There was a significant decrease in screening frequency between the 2011 and 2012 cohorts (8.6% vs. 7.6%, P = 0.0001; adjusted odds ratio 0.89, 95% confidence interval 0.83–0.95). This decrease was most evident amongst patients aged 40 to 49 years (5.6% vs. 4.6%, P = 0.004) and 70 to 79 years (7.9% vs. 6.2%, P = 0.01). A significant decrease was also observed in patients with highest previous PSA value<1.0 (P<0.0001) and 1.0 to 2.49 ng/ml (P = 0.0074).ConclusionsSince the USPSTF recommendation was finalized, there is evidence of continuing decreases in PSA testing by PCPs. PCPs may be shifting toward more selective screening practices, as decreases in screening are most pronounced in the youngest and oldest patients and in those with history of PSA values<2.5 ng/ml.  相似文献   
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Islet cell antibodies (ICA) in the sera of nondiabetic relatives of patients with insulin-dependent diabetes (IDD) are predictive of the disease, a finding that permits the design of intervention strategies to prevent it. However, 85% or more of patients with new onset IDD have no affected relative. We therefore screened 9,696 schoolchildren between the ages of 5 and 18 yr (mean age 10.7 yr) in Pasco County, Florida for ICA in three surveys during 1984/5, 1987/8, and 1990/1 and have followed them prospectively. Approximately 4,000 of these children have been followed for nearly 8 yr. ICA titers > or = 10 Juvenile Diabetes Foundation units on replicate tests were detected in 57 of the children (0.59%). 10 children have developed diabetes so far, and all had ICA detected beforehand. The likelihood of developing IDD among the ICA-positive children was compared with 2,959 age-matched nondiabetic first degree relatives of IDD probands who were screened for ICA by our laboratory during the same time period and also followed prospectively. Of 103 (3.5%) ICA-positive relatives, 31 have developed IDD. Life table analysis reveals no statistically significant differences in the probability of developing IDD between the ICA-positive schoolchildren and ICA-positive first degree relatives (P = 0.3). The estimated risk of developing IDD by 7 yr in the ICA-positive schoolchildren was 45% (95% confidence interval 15-74%) compared with 43% (confidence interval 22-63%) in the relatives. We conclude that ICA appear to be as predictive of IDD in low-risk schoolchildren as they are in high-risk relatives. These data suggest that it is feasible to predict IDD by screening a general population of schoolchildren for ICA and that those found to be positive could be considered, in addition to relatives, for intervention protocols to prevent the disease.  相似文献   
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Infections with gram-positive bacteria are a major cause of morbidity and mortality in humans. Opsonin-dependent phagocytosis plays a major role in protection against and recovery from gram-positive infections. Inborn and acquired defects in opsonin generation and/or recognition by phagocytes are associated with an increased susceptibility to bacterial infections. In contrast, the physiological significance of opsonin-independent phagocytosis is unknown. Type I and II class A scavenger receptors (SR-AI/II) recognize a variety of polyanions including bacterial cell wall products such as lipopolysaccharide (LPS) and lipoteichoic acid (LTA), suggesting a role for SR-AI/II in innate immunity to bacterial infections. Here, we show that SR-AI/II-deficient mice (MSR-A(-/-)) are more susceptible to intraperitoneal infection with a prototypic gram-positive pathogen, Staphylococcus aureus, than MSR-A(+/+) control mice. MSR-A(-/-) mice display an impaired ability to clear bacteria from the site of infection despite normal killing of S. aureus by neutrophils and die as a result of disseminated infection. Opsonin-independent phagocytosis of gram-positive bacteria by MSR-A(-/-) macrophages is significantly decreased although their phagocytic machinery is intact. Peritoneal macrophages from control mice phagocytose a variety of gram-positive bacteria in an SR-AI/II-dependent manner. Our findings demonstrate that SR-AI/II mediate opsonin-independent phagocytosis of gram-positive bacteria, and provide the first evidence that opsonin-independent phagocytosis plays a critical role in host defense against bacterial infections in vivo.  相似文献   
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OBJECTIVE: To determine if children with type 1 diabetes have increased arterial stiffness by estimating augmentation index with the simple noninvasive technique of radial artery tonometry. RESEARCH DESIGN AND METHODS: We studied 98 type 1 diabetic children and 57 healthy control subjects, ages 10-18 years, matched for age, sex, race, and BMI, generating 43 matched pairs. Radial artery tonometry was performed, and blood was collected for analysis of fasting lipids, HbA1c, glucose, and cytokines in all children. RESULTS: Children with diabetes had a significantly higher augmentation index corrected to a heart rate of 75 (AI75) than their matched control subjects. Mean AI75 in type 1 diabetic subjects was 1.11 +/- 10.15 versus -3.32 +/- 10.36 in control subjects. The case-control difference was 5.20 +/- 11.02 (P=0.0031). CONCLUSIONS: Children with type 1 diabetes have increased arterial stiffness compared with healthy control subjects. Radial artery tonometry is a simple noninvasive technique that could be added to the armamentarium of tests used to provide cardiovascular risk stratification in children with type 1 diabetes.  相似文献   
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