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21.
PURPOSE: To evaluate the effectiveness of two marketed home tooth-whitening products. METHODS: A randomized controlled clinical trial involving 87 adults who were randomly allocated into one of three groups: (1) 6% hydrogen peroxide whitening strips, (2) 18% carbamide peroxide whitening gel, and (3) a placebo (fluoride toothpaste) control group. Subjects were instructed individually and then used the given product daily for 2 consecutive weeks. Color was determined in brightness (L*), yellowness (b*) and redness (a*) [color space] at baseline and 8 weeks after dispensing the product by employing a high resolution digital camera (Fuji HC1000 CCD) to image the subject's anterior maxillary teeth under standard polarized lighting conditions. The subjects also completed a questionnaire on self-satisfaction with the treatment outcome. RESULTS: One-way ANOVA (Bonferroni test) demonstrated significant differences in color between the three groups with changes in brightness (L*, P< 0.001), yellowness (b*, P< 0.001) and redness (a*, P < 0.001). Changes in L* a* b* was greatest among those who used the 6% hydrogen peroxide whitening strips. Subjects in the whitening strip group also rated that product significantly (P < 0.01) more favorably than other groups with respect to the amount of whiteness improvement, as well as whitening satisfaction and overall impression while there is no significant difference between the whitening gel and the placebo groups. 相似文献
22.
Matthew Colman Lisa ChoiAntonia Chen MD Lawrence CrossettIvan Tarkin MD Richard McGough MD 《The Journal of arthroplasty》2014
To examine the mortality and implant survivorship of proximal femoral replacement (PFR), revision total hip arthroplasty (REV) and open reduction internal fixation (ORIF) in the treatment of acute periprosthetic fractures of the proximal femur, we retrospectively reviewed 97 consecutive acute periprosthetic proximal femoral fractures from 2000 to 2010. Three groups were defined: PFR (n = 21), REV (n = 19), and ORIF (n = 57). Outcome measures were all-cause mortality, implant failure, and reoperation. Competing Risks survival analysis of overall mortality during the mean 35-month follow-up showed no statistical difference between the three groups (P = 0.65; 12 and 60 month mortality for PFR: 37%, 45%; REV: 16%, 46%; ORIF: 14%, 100%). Implant survival was worse for the PFR group (P = 0.03, 12 and 60-month implant failure rate for PFR: 5%, 39%; REV: 7%, 7%; ORIF 2%, 2%). We conclude that PFR as compared with REV or ORIF may have worse medium-term implant survival, primarily due to instability and dislocation. 相似文献
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24.
In vivo release and turnover of secreted platelet antiheparin proteins in rhesus monkey (Macaca mulatta) 总被引:1,自引:0,他引:1
Musial J; Niewiarowski S; Edmunds LH Jr; Addonizio VP Jr; Nicolaou KC; Colman RW 《Blood》1980,56(4):596-607
Human and rhesus monkey platelets secrete at least two antiheparin proteins: platelet factor 4 (PF4) and low affinity platelet factor 4 (LA-PF4). Neither of these proteins showed species-related antigenic differences. As determined by radioimmunoassay, the levels of PF4 and LA-PF4 antigen per 10(9) monkey platelets amounted to 10.7 and 20.3 microgram, respectively. One milliliter of monkey plasma prepared from blood collected into an anticoagulant composed of EDTA, prostaglandin E1, and theophylline solution contained 22.4 ng LA-PF4 and 8.0 ng PF4. Concentrations of these two platelet-specific proteins in monkeys closely resembled levels found in human platelets and plasma. Infusion of prostacyclin (PGI2) (100 or 300 ng/kg/min) into monkeys for 15 min resulted in a significant decrease of plasma levels of LA-PF4 antigen and of PF4 by 40%--60% (p < 0.0001). This decrease was related to the inhibitory effect of PGI2 on the secretion of platelets stimulated by a catheter or by venipuncture. Longer infusion of PGI2 did not produce further significant change. The supernate obtained after aggregation of human platelets stimulated by thrombin was injected into monkeys receiving PGI2 infusion. The disappearance of LA-PF4 antigen in monkey plasma followed a biphasic exponential curve with half-lives for the fast and slow components of 8.4 and 63 min. PF4 disappeared faster but followed the same pattern (half-lives for the fast and slow component of 2.1 and 70 min). Analysis of the experimental data suggests that the low levels of secreted platelet proteins in monkey plasma are related to their minimal in vivo release and to their rapid clearance. 相似文献
25.
Michael F. T. Koehler Philippe Bergeron Edna F. Choo Kevin Lau Chudi Ndubaku Danette Dudley Paul Gibbons Brad E. Sleebs Carl S. Rye George Nikolakopoulos Chinh Bui Sanji Kulasegaram Wilhelmus J. A. Kersten BrianJ. Smith Peter E. Czabotar Peter M. Colman DavidC. S. Huang Jonathan B. Baell Keith G. Watson Lisa Hasvold Zhi-Fu Tao Le Wang AndrewJ. Souers Steven W. Elmore John A. Flygare Wayne J. Fairbrother Guillaume Lessene 《ACS medicinal chemistry letters》2014,5(6):662-667
26.
Charles Blais Jr. Réjean Couture Guy Drapeau PhD Robert W. Colman Albert Adam PhD 《Arthritis \u0026amp; Rheumatology》1997,40(7):1327-1333
Objective. To investigate the pathophysiologic roles of endogenous bradykinin (BK) and des-Arg9-BK on local and systemic inflammatory responses in a rat model of acute arthritis induced by peptidoglycan-polysaccharide (PG-APS). Methods. Female Lewis rats were injected intra-peritoneally with PG-APS. Selective antagonists of B1 (Lys-[Leu8]-des-Arg9-BK) and B2 (Hoe 140) receptors were infused at 500 μg/kg and 5 mg/kg per day for 6 days, starting 3 days before induction of inflammation, with subcutaneous micro-osmotic pumps. The local inflammatory response was assessed by paw edema, joint swelling, and tissue content of BK and des-Arg9-BK. These peptides were measured by highly sensitive and specific chemiluminescent enzyme immunoassays. Systemic inflammatory reaction was evaluated by the hepatic concentration of the type 2 acute-phase protein T-kininogen. Results. PG-APS induced significant paw edema and joint swelling 24-72 hours after intraperitoneal injection. The maximal responses to PG-APS observed at 72 hours were significantly reduced (31-38%) by the combination of both B1 and B2 receptor antagonists at 5 mg/kg per day. PG-APS induced a significant increase of BK (up to 5.3-fold) and des-Arg9-BK (up to 4.1-fold) 72 hours after challenge. Liver T-kininogen content was increased by 5.3-, 7.7-, and 5.8-fold at 24, 48, and 72 hours, respectively, after PG-APS injection. At 24 hours, Hoe 140 and Lys-[Leu8]-des-Arg9-BK increased liver T-kininogen content by 43% and 45%, respectively, but they had no effect at 72 hours. Conclusion. The results indicate that endogenous kinins are involved in local and systemic acute inflammatory responses, through both B1 and B2 kinin receptors, in the model of PG-APS-induced arthritis. 相似文献
27.
28.
Thériault François L. Hawes R. A. Garber B. G. Momoli F. Gardner W. Zamorski M. A. Colman I. 《Social psychiatry and psychiatric epidemiology》2020,55(5):581-588
Social Psychiatry and Psychiatric Epidemiology - Major depression is a leading cause of morbidity in military populations. However, due to a lack of longitudinal data, little is known about the... 相似文献
29.
Introduction
To date, evidence of the effectiveness of endodontic treatment and criteria of success have mainly been considered in terms of clinical outcome, and there is a lack of information of treatment outcomes from patients' perspectives. This study aimed to assess changes in quality of life after endodontic treatment and to determine if changes in quality of life were associated with changes in patient-perceived oral health and clinical assessments of success.Methods
This longitudinal study involved 279 subjects. Patient-reported outcome measures based on oral health–related quality of life was assessed using the short form of the Oral Health Impact Profile (OHIP-14). The patients completed the assessments before endodontic treatment and 1 month and 6 months after root canal obturation. A global oral health transition assessment was ascertained by a single (global) item rating of oral health improvement and clinical assessment mainly based on the Periapical Index (PAI) of periapical radiographs.Results
There were significant changes in OHIP-14 scores over the study period after conventional orthograde endodontic treatment (from pretreatment–6 months postobturation) (P < .001). The magnitude of statistical change (effect size) was moderate (0.61) in the short-term (after 1 month) and large (0.71) in the longer-term (after 6 months). Changes in the OHIP-14 was associated with changes in patient self-rating oral health status (P < .001), which was also associated with changes in PAI scores (P < .05).Conclusions
Endodontic treatment improves quality of life. The OHIP-14 measure is both sensitive and responsive to endodontic treatment and is likely to be useful in understanding patients' perspectives of outcomes from endodontic care. 相似文献30.
Role of angiogenic factors/cell adhesion markers in serum of cirrhotic patients with hepatopulmonary syndrome 下载免费PDF全文