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1.
Journal of Neuro-Oncology - Understanding the molecular landscape of glioblastoma (GBM) is increasingly important in the age of targeted therapy. O-6-Methylguanine-DNA methyltransferase (MGMT)...  相似文献   
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The aim of this systematic review and meta‐analysis was to analyze the effects of grape seed extract (GSE) on glycemic control and serum lipoproteins, inflammation and body weight. Two independent authors systematically searched online databases including EMBASE, Scopus, PubMed, Cochrane Library, and Web of Science from inception until May 30, 2019. Cochrane Collaboration risk of bias tool was applied to assess the methodological quality of included trials. The heterogeneity among the included studies was assessed using Cochrane's Q test and I‐square (I2) statistic. Data were pooled using a random‐effects model and weighted mean difference (WMD) was considered as the overall effect size. Fifty trials were included in this meta‐analysis. Pooling effect sizes from studies demonstrated a significant decrease in fasting plasma glucose (FPG) (WMD): ?2.01; 95% confidence interval (CI): ?3.14, ?0.86), total cholesterol (TC; WMD: ?6.03; 95% CI: ?9.71, ?2.35), low‐density lipoprotein (LDL) cholesterol (WMD: ?4.97; 95% CI: ?8.37, ?1.57), triglycerides (WMD: ?6.55; 95% CI: ?9.28, ?3.83), and C‐reactive protein (CRP) concentrations (WMD: ?0.81; 95% CI: ?1.25, ?0.38) following GSE therapy. Grape seed did not influence HbA1c, HDL cholesterol levels, and anthropometric measurements. This meta‐analysis demonstrated that GSE intake significantly reduced FPG, TC, LDL cholesterol, triglycerides, and CRP levels.  相似文献   
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SmartPrep is a rotating instrument for dentin caries excavation made from a special polymer. The manufacturer's product information stated that SmartPrep removes carious dentin selectively. This in vitro study compared the efficiency of SmartPrep with conventional tungsten carbide bud burs. Fifty extracted teeth were split in the center of a carious lesion. The 100 specimens were randomly divided into five groups. Five dentists were asked to excavate 10 teeth each: one half with SmartPrep and the corresponding half with conventional bud burs. The time needed for the caries excavation was measured. Subsequently, histological specimens were produced from all cavities and analyzed by light-microscope after Mallory-Azan-staining. The thickness of the remaining caries was measured (< 1 mm or > 1 mm). The time expended was analyzed using the paired t-test. The results were analyzed for the remaining caries and thickness of the carious layer for every tooth, using the non-parametric Wilcoxon test for combined random samples. A binary logistical regression was performed to determine the influence of the three variables (tooth, sections or bur) on the criteria "caries" or "carious layer thickness (> 1 mm)." The average time to excavate a cavity with SmartPrep was 208.1 seconds, and it was 228.32 seconds with conventional bud burs. The difference between the recorded times was not statistically significant (p > 0.05). In 37 of 50 teeth, the number of carious sections was higher in the SmartPrep group than in the bud bur group. In nine teeth, the quantity of carious sections was higher in the bud bur group than in the SmartPrep group. Four teeth showed no difference in the number of carious sections. The results were statistically significantly different (p < 0.001). In 30 teeth, the number of carious sections with a carious layer thicker than 1 mm was higher in the SmartPrep group compared with the bud bur group. In nine teeth, the number of carious sections was higher in the bud bur group than in the SmartPrep group. Eleven teeth showed no difference in thickness of the carious dentin layer. These results were statistically significantly different (p = 0.003). Binary logistical regression showed that only the variable "bur" (bud bur or SmartPrep) influenced the results concerning the criterion "caries" (p < 0.001).  相似文献   
6.
OBJECTIVES: The aim of the present study was to assess the structural reaction of intact dentine to Carisolv in vivo and in vitro. METHODS: For the in vivo study occlusal cavities were prepared in 48 caries-free molars in Wistar rats (age: three months) and Carisolv-solution was placed into the cavities of 24 M for 1, 10 and 20 min. Twenty four contralateral molars served as controls and were treated with an inert liquid containing purified water, carmellose and erythrosin for corresponding periods. For the in vitro study 24 rat molars were resected en bloc and fractured to expose an area of crown dentine area. Molars were demineralised with EDTA for eight weeks to expose the collagenous dentinal matrix. One half of the specimens was then coated with Carisolv-solution for 20 min. The other half served as a control and was coated with an inert solution for 20 min. RESULTS: In the in vivo specimens no signs of pulp cell damage were observed in the experimental group. The odontoblastic processes were destroyed in proximity to the floor of the cavity but were intact in the inner portion of dentinal tubules in experimental molars and a mechanical damage was noted in the control molars. In the in vitro specimens no structural discrepancy was detected between the experimental molars and the control molars in collagen fibrils of demineralised dentine. CONCLUSIONS: Carisolv causes destruction of cellular components of odontoblastic processes but does not attack healthy collagen fibrils.  相似文献   
7.
This prospective longitudinal 3-year study compared clinical parameters and implant success rates of removable superstructures supported by both teeth and implants in patients with treated generalized aggressive periodontitis (GAP) and of cemented, implant-retained fixed superstructures in periodontally healthy patients. A total of 17 partially edentulous patients with 54 implants took part in the study. Nine patients with treated GAP received removable superstructures according to the Marburg double crown system, and eight periodontally healthy patients received fixed superstructures. Teeth were examined 2 to 4 weeks before extraction of the nonretainable teeth (baseline) and 3 weeks after insertion of the definitive abutments. Every 3 months over a 3-year period, clinical parameters were recorded and the composition of the subgingival microflora was determined. Intraoral radiographs were obtained at baseline, just after insertion of the superstructure, and 1 and 3 years later. Both groups showed mean plaque and gingival indices below 0.43 at implants and teeth. Mean probing depths around implants increased by approximately 0.7 mm and remained virtually constant for the teeth. Mean attachment loss at implants was 0.9 mm in GAP patients and 0.5 mm in healthy patients. The morphologic distribution of microorganisms in both groups showed healthy conditions. Moderate bone loss at teeth and implants was registered. Implant success rates were 100% in the healthy patients and 97.6% in the GAP patients. No significant differences were seen in the results between the groups.  相似文献   
8.
The aim of this prospective longitudinal study of patients treated for generalized aggressive periodontitis (GAP) was the clinical, microbiologic, and radiologic longitudinal evaluation of implants placed into bone regenerated by the guided bone regeneration (GBR) technique. Ten patients with GAP who had lost either one or two maxillary incisors or premolars through periodontal disease and whose alveolar bone was neither high nor wide enough for implant placement were enrolled in the study. GBR was carried out in a two-stage procedure using titanium-reinforced extended polytetrafluoroethylene membranes and titanium screws. No bone graft or bone substitute materials were used. After 6 to 8 months, the membranes and supporting screws were removed, and a total of 15 implants (Nobel Biocare) were placed. The control group comprised 10 periodontally healthy patients who had a total of II implants (Nobel Biocare) placed in the maxilla (incisor and premolar region) without GBR because of aplasia, trauma, or endodontic lesions. All patients were examined 2 to 4 weeks before extraction of the nonretainable teeth (baseline) and again immediately after placement of the superstructure. Further examinations were performed within the framework of a 3-month recall schedule over a 3-year period. At each session, clinical parameters (probing pocket depths, bleeding on probing, gingival recession, clinical attachment level, Gingival Index, and Plaque Index) were recorded at teeth and implants, and the composition of the subgingival microflora was determined by dark-field microscopy and DNA probe. Intraoral radiographs were taken for control purposes at baseline, immediately after insertion of the superstructure, and 1 and 3 years later. The GBR technique yielded a horizontal and vertical bone gain of 4.5 to 7.0 mm in the GAP patients. The clinical, microbiologic, and radiologic findings indicated healthy periodontal and periimplant conditions in both patient groups throughout the study. However, a slightly increased attachment loss (0.65 mm) and bone loss (1.78 mm) were recorded at the implants in the regenerated bone after 3 years of loading. The 3-year implant survival rate was 100% in both groups. The possibility of continuous attachment loss and bone loss occurring at teeth and implants in regenerated bone cannot be ruled out in patients treated for aggressive periodontitis. The prognosis for the retention of the teeth and implants is thus open to question.  相似文献   
9.
PURPOSE: The aim of this in vitro study of titanium abutments was to investigate the extent of treatment traces, the roughness depth, and the quantity of titanium or, in the case of coated abutments, titanium nitride (TiN) removed from the surface after treatment with various instruments. MATERIALS AND METHODS: Eleven uncoated, mechanically smoothed abutments and 11 TiN-coated abutments were used. The abutments were treated with titanium, steel, and plastic curettes; a rubber cup; an ultrasonic scaler with a steel tip; and an air scaler and cleaning powder. There were two 2 x 2-mm test fields on each abutment; each was subjected to standardized treatment with an instrument. The untreated surfaces of each abutment served as controls. The roughness depth (Rz) and profile height of treated and untreated surfaces were measured with a profilometer; profile height served as a basis for determining the amount of substance removed by treatment. The treatment traces were analyzed by scanning electron microscopy and light microscopy. RESULTS: Both the ultrasonic scaler and the steel and titanium curettes left pronounced traces on the uncoated abutments and increased Rz. Substantial substance removal was recorded following the use of the ultrasonic scaler (17.57 +/- 2.87 microm) and the steel curettes (8.48 +/- 2.81 microm) on the uncoated abutments. In tests of the coated abutments, measurable substance removal (4.80 +/- 0.99 microm) and increased roughness depth were noted only with use of the steel curettes. The treatment traces left by the other instruments were distinctly less pronounced than on the uncoated abutments. Light microscopy revealed detachment of the TiN coating after use of the ultrasonic scaler, titanium curettes, and steel curettes. Slight to moderate treatment traces were recorded after use of the rubber cup; no substance removal was observed. On the TiN-coated abutments, only slight treatment traces, if any, were recorded, and there was no substance removal. A planing effect (ie, an Rz decrease of 66.4%) was observed. The plastic curette and the air scaler caused no damage to the titanium or TiN surfaces. DISCUSSION AND CONCLUSION: The TiN-coated abutments displayed fewer treatment traces, less roughness depth, and less substance removal after being treated with various instruments. Two concerns, however, are the detachment of the coating after only few actions with steel and titanium curettes or with an ultrasonic scaler with steel tip, and the greater initial roughness depth of coated implants.  相似文献   
10.
While uncertainty is ubiquitous in medical practice, minimal work to date has been performed to analyze the cause and effect relationship between uncertainty and patient outcomes. In medical imaging practice, uncertainty in the radiology report has been well documented to be a source of clinician dissatisfaction. Before one can effectively create intervention strategies aimed at reducing uncertainty, it must first be better understood through context- and user-specific analysis. One strategy for accomplishing this task is to characterize the source of uncertainty and create user-specific uncertainty profiles which take into account a number of provider-specific variables which may contribute to report uncertainty. The resulting data can in turn be used to create real-time report uncertainty metrics aimed at providing uncertainty analytics at the point of care, for the combined purposes of decision support, improved communication, and enhanced clinical/economic outcomes.  相似文献   
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