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991.
992.
A study was performed to evaluate the influence of mandibular lateral excursion, group function and canine guidance on vestibular cervical dental abfraction (VCDA). Thirty-six individuals of both sexes, aged 20 to 45 years, with full natural dentition with at least one tooth with VCDA were selected at the San Marcos University Clinic. We evaluated number of teeth with VCDA per side (left and right), tooth type and lateral excursive movement (canine guidance or group function) affecting it. The results showed no statistical difference (p > 0.05). The tooth type most often showing VCDA was the first lower premolar, with 30.8% on the right side and 36.4% on the left. Moderate positive correlation was found between age and VCDA (R = 0.40). It is concluded that group function during lateral excursion may contribute to presence of VCDA.  相似文献   
993.
Objectives: The present study aims to identify radiographic methods revealing data that are most representative for the true peri‐implant bone as assessed by histology. Materials and methods: Eighty implants were placed in 10 minipigs. To assess matching between different image modalities, measurements conducted on intra‐oral digital radiographs (IO), cone beam computer tomography (CBCT) and histological images were correlated using Spearman's correlation. Paired tests (Wilcoxon test) were used to determine changes in the bone parameters after 2 and 3 months of healing. Results: Significant correlations between bone defect depth on IO and histological slices (r=+0.7, P<0.01), as well as on CBCT images and histological slices (r=+0.61, P<0.01), were found. CBCT and IO images deviate, respectively, 1.20 and 1.17 mm from the histology regarding bone defects. No significant correlations were detected between fractal analysis on CBCT, intra‐oral radiography and histology. For bone density assessment, significant but weaker correlations (r=+0.5, P<0.01) were found for intra‐oral radiography vs. histology. Significant marginal bone‐level changes could be observed after 3 months of healing using intra‐oral radiography. Conclusions: This study allowed linking radiographic bone defect depth to the histological observations of the peri‐implant bone. Minute bone changes during a short‐term period can be followed up using digital intra‐oral radiography. Radiographic fractal analysis did not seem to match histological fractal analysis. CBCT was not found to be reliable for bone density measures, but might hold potential with regard to the structural analysis of the trabecular bone. To cite this article:
Corpas LS, Jacobs R, Quirynen M, Huang Y, Naert I, Duyck J. Peri‐implant bone tissue assessment by comparing the outcome of intra‐oral radiograph and cone beam computed tomography analyses to the histological standard
Clin. Oral Impl. Res. 22 , 2011; 492–499
doi: 10.1111/j.1600‐0501.2010.02029.x  相似文献   
994.
Various assays have been developed to diagnose dengue virus infection, relying on techniques from the fields of serology and molecular biology. Many of these assays have been successful, but there is still an urgent need for accurate, simple and rapid diagnostic assays to diagnose dengue virus infection and to assist in patient management. Using a panel of well-characterized sera and a collection of retrospective samples obtained during the dengue epidemics that occurred in Belém, Brazil, between 2002 and 2009, a modified immunoglobulin M-specific capture enzyme-linked immunosorbent assay (Rapid-MAC-ELISA) was evaluated and compared with the “gold standard” MAC-ELISA, in order to assess the specificity, sensitivity, stability, reproducibility and cost-effectiveness of this new assay. These results demonstrated that the Rapid-MAC-ELISA is comparable to the MAC-ELISA in terms of sensitivity and specificity and is highly reproducible; additionally, it is easily performed, less expensive than other available formats and can be completed within three hours. Furthermore, the Rapid-MAC-ELISA can be used for the diagnosis of dengue virus infections in resource-limited areas where dengue is endemic.  相似文献   
995.
Detection of hepatitis B virus (HBV) serological markers in dried blood spot (DBS) samples by enzyme immunoassay (ELISA) has not yet been fully optimized. In this study, the ability to detect three HBV markers (HBsAg, anti-HBc, and anti-HBs) was evaluated in DBS samples using a modified commercial ELISA. Matched serum and DBS samples were obtained from individuals with or without a past history of HBV infection. Sera samples were tested according to the manufacturer's instructions, but for DBS testing, paper diameters, elution buffer, volume of input sample, and cut-off values were evaluated to optimize the assay. Stability studies were done on DBS stored at for up to 180 days at different temperatures. The absorbance values that yielded the maximum sensitivity and specificity were determined based on the area under the ROC curve (AUROC) and chosen as the cut-off value. Using this parameter, sensitivity was 90.5%, 97.6%, and 78% for anti-HBc, HBsAg, anti-HBs assays, respectively. Specificity was 92.6%, 96.7%, and 97.3% for anti-HBc, HBsAg, and anti-HBs assays, respectively. HBV markers could be detected in DBS samples until 63 days after sample collection at most temperatures, but storage at -20°C yielded more consistent results. These results indicate that modified ELISA can be used to detect HBV markers in DBS samples, particularly if the samples are stored appropriately.  相似文献   
996.
A new protocol for producing polyclonal antibody against hepatitis A virus (HAV) is described. Twenty hens were immunized three times with a commercial HAV vaccine and HAV from a cell culture with three types of adjuvants: CpG oligodeoxynucleotides (CpG-ODN), incomplete Freund's adjuvant and an alum adjuvant. In each of the last two booster inoculations, blood from the birds was collected and tested for HAV antibodies. Egg yolk was separated from egg white and immunoglobulin Y (IgY) antibody was then purified by polyethylene glycol 6000. The mean yield of total protein in yolk was 22.62 mg/mL. Specific activity of the antibody was tested using commercial ELISA, Western blotting, and in vitro neutralization assay demonstrating that anti-HAV IgY bound specifically. After the first immunization, birds immunized with HAV from cell culture plus incomplete Freund's adjuvant with/without CpG-ODN showed highest levels of anti-HAV IgY in serum (p < 0.05). Viral combination with CpG-ODN resulted in early response of anti-HAV serum in hens, reflecting the amount of IgY transferred to the egg yolk (p < 0.05). The results suggest that egg yolk may be a large scale source of specific antibodies against hepatitis A virus. Further applications of this method have yet to be tested.  相似文献   
997.
998.
No controlled studies exist regarding the pharmaceutical reduction of ataxia symptoms in ataxia telangiectasia (A-T). In a multicenter, double-blind, randomized, placebo-controlled crossover trial, oral betamethasone (BETA) and placebo were compared in terms of their reduction of ataxia symptoms as assessed with the International Cooperative Ataxia Rating Scale (ICARS). In this study of 13 A-T children, betamethasone reduced the ICARS total score by a median of 13 points in the intent-to-treat population and 16 points in the per-protocol population (ie, median percent decreases of ataxia symptoms of 28% and 31%, respectively). In conclusion, Oral betamethasone could be a promising therapy to relieve ataxia symptoms in A-T patients; however, long-term effectiveness and safety must be established. (Current Controlled Trials, number ISRCTN08774933.) ? 2012 Movement Disorder Society.  相似文献   
999.
1000.
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