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11.
The aim of this study was to evaluate retentive strengths of three adhesive/resin cement/fiber post systems to the apical third of post-space dentin varying the application method of the luting agent. ENA post (Micerium, Avegno, Genova, Italy), FRC Postec Plus (Ivoclar Vivadent, Schaan, Liechtenstein), and Anatomical Post (Dentalica, Milano, Italy) were luted in prepared root canals using the adhesive system and resin cement provided by the respective manufacturer. Each group was randomly divided into three subgroups (n = 10) according to the technique used to place the luting agent into post space: using a lentulo spiral, applying the cement onto the post surface, and injecting the material with a specific syringe. A push-out test was performed on sections from the post-space apical part of each specimen. All fractured specimens were observed using a stereomicroscope. Bond strength values were not significantly affected by the application technique of the luting agent (p > 0.05). The ENA post system showed the highest retentive strengths. The other two post groups exhibited similar bond strengths to each other. Microscopic analysis revealed a prevalence of post/cement and mixed failures.  相似文献   
12.
OBJECTIVES: The aim of this study was to assess the systemic effects of treating severe widespread periodontitis in a population of otherwise healthy individuals by examining treatment associated changes in markers of inflammation that are also implicated in cardiovascular atherosclerotic diseases. The potential impact of specific polymorphisms in cytokine genes known to influence both periodontitis and cardiovascular diseases was also examined. MATERIALS AND METHODS: A convenience sample of patients affected with severe generalised periodontitis was enrolled into a prospective single blind longitudinal intervention trial with a 6 months follow-up. Serum C-reactive protein (CRP) and interleukin-6 (IL-6) levels were assessed by high-sensitivity assays. Serological and clinical periodontal parameters were evaluated at baseline, 2 and 6 months after completion of non-surgical periodontal therapy. Results: In the 94 subjects that completed this pilot trial improvements in all clinical periodontal parameters were achieved. These were accompanied with significant reductions in serum IL-6 and CRP concentrations. In a multivariate model, serum CRP levels were significantly associated with the outcome of periodontal treatment after correcting for potential covariates (age, body mass index, gender, smoking) and polymorphisms in the IL-6 (-174 C/G) and IL-1A (-889) genes. A median decrease in serum CRP of 0.5 mg/l (95% CI 0.4-0.7 mg/l) was observed 6 months after completion of periodontal therapy in this population. Subjects with above average response to periodontal therapy (<30 residual pockets and <30% of sites bleeding on probing) accounted for the observed improvement in serum CRP. CONCLUSIONS: Control of periodontitis, achieved with non-surgical periodontal therapy, significantly decreased serum mediators and markers of acute phase response. The significance of the serum response was associated with the half of the population that responded better to non-surgical periodontal therapy. The results of this pilot study indicate that severe generalised periodontitis causes systemic inflammation. This is consistent with a causative role of periodontitis in atherogenesis.  相似文献   
13.
Rogers J  Maurizio SJ 《RDH》1999,19(12):49, 52-49, 54
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14.
Atomic force microscopy (AFM) was applied to the investigation of the adsorption of glucose oxidase (GOd) molecules onto the surface of a gold amperometric glucose biosensor. The study was carried out in order to check the dependence of the enzyme density, as revealed by AFM images, on the original concentrations in the adsorption manufacturing solutions. At the highest concentrations (1–5×10?3 mg dm?3) the gold surface appeared to be completely covered by a thick and strongly attached molecular layer. At intermediate concentration ranges (0.1–1×10?3 mg dm?3), the clusters of GOd molecules appeared sparsely scattered onto the gold surface, showing the underlying microcrystal organisation typical of untreated surfaces. At the lowest concentration used (10?5 mg dm?3) single molecules were visualised in a lying position on gold granules or within surface microslits. The molecule shape fits with the morphometric data already known for GOd. When compared to electrochemical data resulting from tests carried out at the same concentration ranges, a significant correspondence of the molecular adsorption patterns with the enzyme amperometric responses was observed.  相似文献   
15.
The genetic power of a Brazilian three-generation family with generalized aggressive periodontitis (GAgP) has been reported. The empirical logarithms of the odds (LOD) score thresholds for genetic linkage analysis of complex diseases proposed by Haines rely on confirmation from independent datasets. This study estimated the power of another large Brazilian family with GAgP for future linkage analysis. The three-generation family was seen at the Dental School of the Federal University of Bahia. Following the previously described methodology, full-mouth periodontal probing at 6 sites/tooth was performed in all 19 family members. Six out of 12 siblings were affected with GAgP. All affected family members were non-smokers and did not present diabetes or any other systemic condition or consanguinity. A parametric simulation (θ=0) was performed on 100 replicates using the statistical software SLINK for linkage analysis. There was maximum expected LOD scores of 3.75 and 3.45 at penetrance rate F=0.98, and both studied phenocopy rates P=0.0 and P=0.02, respectively. The power of the study increased with the increase of the adopted penetrance rates in both studied phenocopy rates. The studied Brazilian three-generation family showed statistical power for future genetic linkage analysis of candidate genes to GAgP.  相似文献   
16.
Patent foramen ovale (PFO) is a common congenital anatomical defect in the general population with a mean prevalence of 20 %. Transcranial Doppler sonography and echocardiography, both with infusion of agitated saline as an echo contrast, have been introduced for the diagnosis of PFO. Transesophageal echocardiography is considered the gold standard. Several studies have suggested an association between cryptogenetic stroke and PFO, but the role of this condition as a risk factor for stroke is still debated. The aims of this prospective multicentre study are the evaluation of PFO prevalence in the whole ischemic stroke population and the identification of a stroke recurrence profile risk in patients with PFO. All consecutive patients admitted for acute ischemic stroke and with a confirmed diagnosis at discharge are eligible cases for the study. Demographic and vascular risk factors are registered. Clinical severity is summarized by the National Institute of Health stroke scale. Echocardiographic and transcranial studies are performed in each patient to detect the presence of PFO. Prevalence of PFO will be calculated with 95 % CIs. Univariate analysis will be performed to detect the correlation of PFO with different registered factors and multivariable analysis with PFO as independent variable. The present study should contribute to better identify the role of PFO in ischemic stroke risk and recurrence-related events. Qualifying findings of the study are represented by the high number of enrolled patients, the prospective methodology of the study and the presence of secondary instrumental endpoints.  相似文献   
17.
Papi C  Koch M  Capurso L 《Chemotherapy》2005,51(Z1):110-114
Treatment of symptomatic diverticular disease of the colon is aimed at the relief of symptoms and the prevention of major complications. The efficacy of fiber supplementation and of anticholinergic and spasmolytic agents remains controversial. Antibiotics are commonly used in the treatment of inflammatory complications of diverticular disease. Data from open labelled and randomized controlled trials do suggest the efficacy of rifaximin in obtaining symptomatic relief in patients with diverticular disease. Approximately 30% therapeutic gain compared to fiber supplementation only can be expected after one year of intermittent treatment with rifaximin. Considering the safety and tolerability of rifaximin, this drug can be recommended for patients with symptomatic uncomplicated diverticular disease.  相似文献   
18.
Portal vein thrombosis (PVT) is a well-known and relatively common complication of liver cirrhosis. In the past, PVT was considered as a contraindication for liver transplantation (LT). To characterize prevalence, risk factors, perioperative management and outcome of PVT in the setting of LT, the English literature published between 1991 and 2011 was reviewed.Of 6807 articles, 280 were selected, and 39 experiences were analyzed in detail (methodology, type and duration of treatments, peri-operative management, strategy to avoid recurrence, strengths and weaknesses, Oxford evidence level, citations). 3/39 studies were prospective; 9/39 were based on prospectively recorded databases; no studies of 1, 2a, 3a level of evidence were present; 5/39 were recognized as level 2b, 23/39 as level 3b, and 8/39 as level 4.High complication rate has been reported with consequent effect on graft and patient survival. Overall, PVT presents today good results similar to those obtained in patients without PVT undergoing LT even if they require a higher transfusion number and a longer ICU/hospital stay.Reported cases were retrospectively stratified according to Yerdel classification. Grade 1–2 patients (76%) do well with eversion thromboendovenectomy, resection of damaged vein and porto-portal anastomosis. Results of patients with grade 3–4 (24%) are inferior, however data on outcome in this subsets are fragmented and do not allow a reliable analysis. Moreover, results obtained in grade 3–4 cases are better in transplant centers with large specific experience. The small number of reports suggests caution.The role of anticoagulant treatment is still debated. Although in cirrhotics with PVT LT remains a demanding procedure, PVT should not be considered a contraindication anymore.  相似文献   
19.
Class I obesity conveys an increased risk of comorbidities, impairs physical and mental health-related quality of life, and it is associated to an increased psychosocial burden, particularly in women. The need for effective and safe therapies for class I obesity is great and not yet met by nonsurgical approaches. Eligibility to bariatric surgery has been largely based on body mass index (BMI) cut points and limited to patients with more severe obesity levels. However, obese patients belonging to the same BMI class may have very different levels of health, risk, and impact of obesity on quality of life. Individual patients in class I obesity may have a comorbidity burden similar to, or greater than, patients with more severe obesity. Therefore, the denial of bariatric surgery to a patient with class I obesity suffering from a significant obesity-related health burden and not achieving weight control with nonsurgical therapy simply on the basis of the BMI level does not appear to be clinically justified. A clinical decision should be based on a more comprehensive evaluation of the patient’s current global health and on a more reliable prediction of future morbidity and mortality. After a careful review of available data about safety and efficacy of bariatric surgery in patients with class I obesity, this panel reached a consensus on ten clinical recommendations.  相似文献   
20.
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