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排序方式: 共有1801条查询结果,搜索用时 203 毫秒
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Nina Lundegren Melvin M Sohrabi Margareta Molin Thorén Sigvard Åkerman 《Acta odontologica Scandinavica》2019,77(4):296-302
Objective: To determine the prevalence of dental prosthetic restorations in an adult population, to study the agreement between self-reports and clinical findings of prosthetic restorations, and to study answers from a questionnaire in relation to the prevalence of prosthetic restorations.Material and methods: A questionnaire was sent to a sample of 10,000 adults. A further sample of 1000 individuals was invited to answer the questionnaire and also participate in a clinical study. The agreement between self-report and clinical findings was analyzed, as were the associations between prosthetic restorations and questionnaire responses, using the chi2 test.Results: A total of 40% of the sample had fixed dental prostheses (FDP), 2.7% had removable dentures. The agreement between self-report and clinical findings was 93%. 34.7% of the individuals with no prosthetic restorations were university graduates and 4% of individuals with removable complete dentures. Oral health had the greatest impact on the quality of life of younger individuals with FDP, with an OHIP-14 (Oral Health Impact Profile) score of 7.3 for the age group 20–39 years compared to 4.9 for the age group 65–89 years. Conclusion: The questionnaire method can be a cost-effective way to determine the prevalence of prosthetic restorations. 相似文献
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Mercury vapor release from dental amalgam in patients with symptoms allegedly caused by amalgam fillings 总被引:1,自引:0,他引:1
The aim of this study was to determine whether a group of patients with symptoms, self-related to their amalgam restorations, experienced an exposure to mercury vapor from their amalgam restorations that reached the range at which subtle symptoms have been reported in the literature. Furthermore, the aim was to determine whether the mercury exposure for these patients was significantly higher than for controls with no reported health complaints. The symptom group consisted of 10 consecutively selected patients from a larger group, referred by their physicians for investigation into any correlation between subjective symptoms and amalgam restorations. The control group consisted of 8 persons with no reported health complaints. The intra-oral release of mercury vapor was measured between 7 :45 a.m. and 9 :00 p.m. at intervals of 30–45 min. following a standardized schedule. The mercury levels in plasma, erythrocytes, and urine were also determined. The calculated daily uptake of inhaled mercury vapor, released from the amalgam restorations, was less than 5% of the daily uptake calculated at the lower concentration range given by the WHO (1991), at which subtle symptoms have been found in particularly sensitive individuals. The symptom group had neither a higher estimated daily uptake of inhaled mercury vapor, nor a higher mercury concentration in blood and urine than the control group. The study provides no scientific support for the belief that the symptoms of the patients examined originated from an enhanced mercury release from their amalgam restorations. 相似文献
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Margareta Ringqvist Marie-Louise Walker-Engstr?m Ake Tegelberg Ivar Ringqvist 《American journal of orthodontics and dentofacial orthopedics》2003,124(1):53-60
The aim of this prospective, randomized study was to analyze dental and skeletal side effects after 4 years of treating obstructive sleep apnea (OSA) patients with a mandibular advancement device (MAD) compared with uvulopalatopharyngoplasty (UPPP). With the appliance in position, the mandible was advanced 50% of maximum protrusion capacity (ie, 4-6 mm); the vertical opening between the incisal edges was, on average, 3 mm. Thirty patients in the MAD group and 37 in the UPPP group completed the 4-year follow-up. There were no differences between the MAD and the UPPP groups in any of the dental or skeletal variables measured after the 4-year treatment period. In the MAD group, small but statistically significant changes were found: there was a posterior rotation of the mandible (mandibular line [ML]/nasion-sella line [NSL]) (mean 0.5 degrees [95% confidence interval (CI) 0.1-0.8 degrees ]). Correlated to the posterior rotation of the mandible, the distances incision superius ML, incision superius-NSL, and incision inferius-NSL increased by means (95% CI) of 0.7 (0.5-1.2), 0.8 (0.4-1.1), and 1.3 (0.8-1.8) mm, respectively. Overjet and overbite did not change significantly, nor was there a significant change in the mandibular length. The observed changes were considered clinically insignificant because overbite and overjet stayed within normal limits. Only the vertical position of the maxillary incisors in relation to ML changed to the extent that the 95% CI of the mean for the change was outside that of the mean of the change in the UPPP group and measurement error. Treatment of OSA with a dental appliance is probably a lifelong process, and long-term follow-up studies should therefore be undertaken to control both the treatment effect on OSA and the side effects on the masticatory system. 相似文献
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PURPOSE: The aim of the present study was to evaluate the clinical outcome of extensive Empress onlays retained with resin-bonded cement. MATERIALS AND METHODS: One hundred thirty extensive ceramic onlays were placed in premolar and molar regions in 91 patients treated by 2 general practitioners between 1997 and 2000. Seventy-seven percent of the constructions were luted with chemically cured resin composite cement and 23% were luted with dual-cured resin cement. Fifty-nine patients with 81 restorations were clinically evaluated independently by 2 calibrated examiners using the California Dental Association protocol. The mean time in function for all restorations at examination was 49 months. RESULTS: Seventy-five (93%) onlays were still in function after 4 years. Six onlays (7.3%) failed; 1 had lost retention as a result of caries, and 5 had fractured. All failures were in molar regions. CONCLUSIONS: Ceramic onlay therapy is an acceptable treatment alternative over a 4-year period, but further long-term data are necessary before this treatment should be considered for general dental practice. 相似文献
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Background
The risk of venous thromboembolism is enhanced in pregnant carriers of the Factor V Leiden mutation. The primary aim of the study was to compare prothrombin fragments 1 + 2, soluble fibrin and D-dimer levels in pregnant Factor V Leiden mutation carriers with those in non-carriers. Secondary aims were to evaluate whether these biomarkers could predict placenta-mediated complications or venous thromboembolism, and to study blood coagulation after caesarean section with thromboprophylaxis and after vaginal delivery without thromboprophylaxis.Material/Methods
Prothrombin fragments 1 + 2, soluble fibrin and D-dimer levels were studied longitudinally in 476 carriers with singleton pregnancies from gestational weeks 23–25 until 8–10 weeks postpartum.Results
Prothrombin fragments 1 + 2 and D-dimer levels gradually increased during pregnancy. D-dimer levels were higher in carriers, both during pregnancy and puerperium, compared to non-carriers. D-dimer levels above 0.5 mg/l were found in about 30% and 20% of the heterozygous carriers at 4–5 and 8–10 weeks postpartum, respectively. Soluble fibrin levels were mainly unchanged during pregnancy, with no difference between carriers and non-carriers. Biomarker levels were similar in carriers with uncomplicated and complicated pregnancies.Conclusion
Higher D-dimer levels indicate increased blood coagulation and fibrinolysis activity in carriers. The high proportion of carriers with D-dimer levels exceeding 0.5 mg/l postpartum must be considered when assessing the probability of venous thromboembolism. Large overlaps in biomarker levels in normal and complicated pregnancies suggest that these biomarkers cannot be used as predictors. Thromboprophylaxis following caesarean section may prevent increased activation of blood coagulation. 相似文献9.
Research on the sex lives of people with severe mental illness (SMI) most often focuses on dysfunction and the side-effects of medication. We wished to determine how people with SMI experience sex and assess satisfaction with it in a broader evaluation of quality of life. Data were gathered using mixed methods, including a reliable psychometric quality of life instrument, and in-depth interviews. Sex life showed the lowest rating of all quality of life domains, with men indicating lower satisfaction in this area than women. Low satisfaction also correlated with lower scores on the total quality of life index. Sexuality and intimate relations were generally experienced as out of reach or something of secondary importance that had to be controlled, according to many of those suffering from SMI. Programs such as patient disorder-specific or partner assisted interventions, to increase the possibility of sustaining a sex life might need to be added to existing recommendations for people with SMI living in a community. 相似文献
10.
Duration and degree of cyclosporin induced P-glycoprotein inhibition in the rat blood-brain barrier can be studied with PET 总被引:3,自引:0,他引:3
Syvänen S Blomquist G Sprycha M Höglund AU Roman M Eriksson O Hammarlund-Udenaes M Långström B Bergström M 《NeuroImage》2006,32(3):1134-1141
Active efflux transporters in the blood-brain barrier lower the brain concentrations of many drug molecules and endogenous substances and thus affect their central action. The objective of this investigation was to study the dynamics of the entire inhibition process of the efflux transporter P-glycoprotein (P-gp), using positron emission tomography (PET). The P-gp marker [(11)C]verapamil was administered to anesthetized rats as an i.v. bolus dose followed by graded infusions via a computerized pump system to obtain a steady-state concentration of [(11)C]verapamil in brain. The P-gp modulator cyclosporin A (CsA) (3, 10 and 25 mg/kg) was administered as a short bolus injection 30 min after the start of the [(11)C]verapamil infusion. The CsA pharmacokinetics was studied in whole blood in a parallel group of rats. The CsA blood concentrations were used as input to model P-gp inhibition. The inhibition of P-gp was observed as a rapid increase in brain concentrations of [(11)C]verapamil, with a maximum after 5, 7.5 and 17.5 min for the respective doses. The respective increases in maximal [(11)C]verapamil concentrations were 1.5, 2.5 and 4 times the baseline concentration. A model in which CsA inhibited P-gp by decreasing the transport of [(11)C]verapamil out from the brain resulted in the best fit. Our data suggest that it is not the CsA concentration in blood, but rather the CsA concentration in an effect compartment, probably the endothelial cells of the blood-brain barrier that is responsible for the inhibition of P-gp. 相似文献