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Abstract – This report describes an esthetic, conservative, and economical alternative restoration technique for a fractured central incisor using the patient’s own tooth crown piece and a bondable reinforcement glass fiber. Although the long‐term durability of this adhesive post core restoration remains unknown, it remains successful after 1 year.  相似文献   
3.
Aim: In this population‐based study, we aimed to determine the total sleep duration (TSD), its association with socio‐economic status (SES) and behavioural symptoms among schoolchildren. Methods: A cross‐sectional study was performed among schoolchildren in Istanbul. A structured questionnaire evaluating the sleep schedule variables was filled out by their parents. SES was determined according to the Turkish SES scale. Results:  The mean age of 2669 children was 8.2 ± 2.4 years, and 51% of the students were girls. The mean TSD was 10.20 ± 1.04, and the mean bedtime was 21.57 ± 0.56 (both in hours, minutes ± SD). Boys tended to go bed later (p = 0.004) and slept less than girls (p = 0.02). The duration of sleep disruptions increased (p < 0.001), whereas TSD decreased with age (p < 0.001). Multiple linear regression revealed that waking time and TSD decreased significantly (p < 0.05) with higher SES among both girls and boys. Sleep fragmentation was associated with habitual snoring, parasomnias, daytime sleepiness and conduct symptoms. Conclusion: Decreased total sleep duration is more prominent in boys, older children and children among higher socio‐economic status. Insufficient sleep attributed to shortened total sleep duration by age and higher socio‐economic status might have a negative effect on both sleep hygiene and psychological well‐being in schoolchildren.  相似文献   
4.
Context: There is a growing market demand for Hypericum sp., a pharmacologically active plant that has been traditionally used to treat various ailments. However, there have been limited studies on the extract or essential oil of Hypericum lydium Boiss (Hypericaceae).

Objective: This study investigates for the first time the antioxidant, mutagenic and antimutagenic activity of an ethanol extract of H. lydium.

Material and methods: Ethanol extract from aerial parts of H. lydium harvested from Turkey were tested for this mutagenic and antimutagenic activities (2.0–0.002?mg/plate) using Ames Salmonella/microsome test system. 4-Nitro-o-phenylenediamine (4-NPD) (3?μg/plate) for the Salmonella typhimurium TA98 and sodium azide (NaN3) (8?μg/plate) for the S. typhimurium TA100 were used as positive controls. The antioxidant activity, total antioxidant activity and phenolic constituent of the extract (2.0–0.002?mg/mL) was determined by the inhibition of 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), β-carotene-linoleic acid model and by means of Folin–Ciocalteu reagent, respectively.

Results: The extract showed no sign of mutagenicity at the tested concentrations (0.002–2.0?mg/mL), and showed concentration-dependent antimutagenic activity against NaN3 and 4-NPD ranging from 26.8 to 81.5%. The extract was found to be an efficient scavenger of DPPH (IC50 0.165?±?0.23?mg/mL) and to inhibit β-carotene-linoleic acid bleaching (IC50 0.39?±?0.11?mg/mL).

Discussion and conclusion: These findings indicate ethanol extract of H. lydium to be a safe and effective agent that may be incorporated into new strategies for the prevention of cancer and mutagenesis.  相似文献   
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Following heart transplantation, cardiac biomarkers remain elevated for several weeks eventually as a result of membrane leakage of the donor organ. We now test the predictive power of blood levels of troponin T (TNT) measured by the new hsTNT assay (Roche Diagnostics, Roche Diagnostics, Mannheim, Germany) early after heart transplantation. TNT was determined in 141 cardiac allograft recipients and 40 controls. Our findings demonstrate that patients who died within the first year after transplantation had significantly higher median hsTNT serum levels 6 weeks after transplantation (156 ng/l ± 203 vs. 29 ng/l ± 21, P = 0.0002). Using ROC analysis, a serum hsTNT concentration of 33.55 ng/l 6 weeks after transplantation was found to be the best cutoff to predict death at 1 year (HR 0.16, 95%CI:0.05–0.46, P = 0.001) with a sensitivity of 90.91% and a specificity of 70.97%. In addition, survival at 5 years (HR 0.15, 95% CI 0.06–0.35, P < 0.0001) was significantly better among patients below that cutoff value. In multivariate analysis, hsTNT serum level 6 weeks after transplantation emerged as an independent predictor for first‐year mortality (hsTNT–HR 0.90, 95% CI: 0.81–1.00, P = 0.03). Cardiac troponin T concentrations early after transplantation as measured with a highly sensitive assay represent a strong and independent risk predictor of death after heart transplantation.  相似文献   
7.

PURPOSE

Polymethyl methacrylate (PMMA) is the most commonly used denture base material despite typically low in strength. The purpose of this study was to improve the physical properties of the PMMA based denture base resins (QC-20, Dentsply Ltd., Addlestone, UK; Stellon, AD International Ltd, Dentsply, Switzerland; Acron MC; GC Lab Technologies Inc., Alsip, Japan) by copolymerization mechanism.

MATERIALS AND METHODS

Control group specimens were prepared according to the manufacturer recommendations. In the copolymer groups; resins were prepared with 5%, 10%, 15% and 20% acrylamide (AAm) (Merck, Hohenbrunn, Germany) content according to the moleculer weight ratio, respectively. Chemical structure was characterized by a Bruker Vertex-70 Fourier transform infrared spectroscopy (FTIR) (Bruker Optics Inc., Ettlingen, Germany). Hardness was determined using an universal hardness tester (Struers Duramin, Struers A/S, Ballerup, Denmark) equipped with a Vickers diamond penetrator. The glass transition temperature (Tg) of control and copolymers were evaluated by Perkin Elmer Diamond DSC (Perkin Elmer, Massachusetts,USA). Statistical analyses were carried out using the statistical package SPSS for Windows, version 15.0 (SPSS, Chicago, IL, USA). The results were tested regarding the normality of distribution with the Shapiro Wilk test. Data were analyzed using ANOVA with post-hoc Tukey test (P<.01).

RESULTS

The copolymer synthesis was confirmed by FTIR spectroscopy. Glass transition temperature of the copolymer groups were higher than the control groups of the resins. The 10%, 15% and 20% copolymer groups of Stellon presented significantly higher than the control group in terms of hardness. 15% and 20% copolymer groups of Acron MC showed significantly higher hardness values when compared to the control group of the resin. Acrylamide addition did not affect the hardness of the QC-20 resin significantly.

CONCLUSION

Within the limitation of this study, it can be concluded that copolymerization of PMMA with AAm increased the hardness value and glass transition temperature of PMMA denture base resins.  相似文献   
8.

PURPOSE

This study investigated the effect of laser parameters and air-abrasion on the peel strength of silicon-based soft denture liner to different denture resins.

MATERIALS AND METHODS

Specimens (N=180) were prepared out of three different denture base resins (Rodex, cross-linked denture base acrylic resin; Paladent, heat-cured acrylic resin; Deflex, Polyamide resin) (75 mm × 25 mm × 3 mm). A silicon-based soft denture liner (Molloplast B) was applied to the denture resins after the following conditioning methods: a) Air-abrasion (50 µm), b) Er,Cr:YSGG laser (Waterlase MD Turbo, Biolase Technology) at 2 W-20 Hz, c) Er,Cr:YSGG laser at 2 W-30 Hz, d) Er,Cr:YSGG laser at 3 W-20 Hz, e) Er,Cr:YSGG laser at 3 W-30 Hz. Non-conditioned group acted as the control group. Peel test was performed in a universal testing machine. Failure modes were evaluated visually. Data were analyzed using two-way ANOVA and Tukey''s test (α=.05).

RESULTS

Denture liner tested showed increased peel strength after laser treatment with different parameters (3.9±0.4 - 5.58±0.6 MPa) compared to the control (3.64±0.5 - 4.58±0.5 MPa) and air-abraded groups (3.1±0.6 - 4.46±0.3 MPa), but the results were not statistically significant except for Paladent, with the pretreatment of Er,Cr:YSGG laser at 3 W-20 Hz. Polyamide resin after air-abrasion showed significantly lower peel strength than those of other groups (3.1±0.6 MPa).

CONCLUSION

Heat-cured acrylic resin, PMMA, may benefit from Er,Cr:YSGG laser treatment at 3 W-20 Hz irradiation. Air-abrasion of polyamide resins should be avoided not to impair their peel bond strengths to silicon-based soft denture liners.  相似文献   
9.
We prospectively evaluated 59 eyes following uneventful phacoemulsification and intraocular lens implantation with optic coherence tomography at one and seven postoperative days (POD). Acute vitreomacular traction was observed in two eyes (3.3%) at the first POD. Spontaneous resolution occurred in both eyes within one week. The temporary visual loss associated with acute vitreomacular traction syndrome may go unnoticed as visual acuity rapidly improves.  相似文献   
10.
To explore the relationship between self‐efficacy, family environment (cohesion and organization) and metabolic control. Research design and methods: A total of 100 adolescents with diabetes were assessed on a single occasion. Eligibility criteria were an age range of 11–18 yr, diagnosis of type 1 diabetes of at least 1 yr duration, and ability to complete the questionnaire unaided. Adolescents completed self‐efficacy and family environment questionnaires. Metabolic control was assessed by HbA1c. Statistical analysis was performed using Statistical Package for the Social Sciences (SPSS) Version 10.0. Independent paired t‐tests and Pearson's correlation coefficient were used as test methods. Results: Boys and girls were comparable on self‐efficacy, and self‐efficacy scores were quite satisfactory for both boys and girls. There was a significant positive correlation between self‐efficacy and family cohesion in girls, but self‐efficacy was not related to the family environment (cohesion and organization) and metabolic control in the total sample. Conclusion: In the present study, there was no relationship between self‐efficacy, family environment, and metabolic control in the total sample, but in girls, self‐efficacy and family cohesion was positively correlated.  相似文献   
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