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81.
Fluoride varnish applications were applied to two hybrid resin composite materials, Z-100 (3M Dental Products, St Paul, MN, USA) and Esthet-X (Dentsply Caulk, Milford, DE, USA), shades A1 and A2 and a glass ionomer, GC Fuji IX GP Fast (GC Corporation, Tokyo, Japan), shade A2, to evaluate color stability. Specimens (12.6-mm dia x 2.3 mm) were prepared using a polyethylene frame, light-cured and polished through a 1-microm alumina finish. After the initial baseline color measurements, the discs were suspended in Fusayama artificial saliva (FAS) solution at 37 degrees C for 48 hours. Post immersion, the specimens were divided into five groups (n=15 each). The following fluoride varnishes were applied to four groups of test specimens: Duraphat (Colgate Oral Pharmaceutical, Inc, Canton MA, USA), Cavity Shield (OMNII Oral Pharmaceuticals, West Palm Beach, FL, USA), Duraflor (Pharmascience Inc, Montreal, Canada) and Fluor Protector (Vivadent, Ivoclar North America, Amherst, NY, USA). The varnish was allowed to dry for five minutes before immersion. The control group was not coated with varnish, although the specimens were immersed in FAS. All specimens were incubated in newly prepared FAS at 37 degrees C for 24 hours, cleaned with an electric toothbrush and the process repeated using newly prepared FAS. CIE L*a*b* color measurements were recorded five times: at baseline, after 48 hours FAS immersion, after cleaning the first and second fluoride varnish applications and after the final brushing using a commercial toothpaste (Crest). A Minolta CR-300 tristimulus colorimeter with an 8-mm aperture (Ramsey, NJ, USA) was used to record color measurements with the daylight (D65) setting. Calculations were performed for using CIE parameters deltaE*, deltaL*, delta a*, delta b*. Analysis of variance (ANOVA) and post-hoc test (Fisher's PLSD) were used for statistical analysis. After immersion in saliva, the tested glass ionomer (Fuji IX) produced the most significant color changes (deltaE*=1.19 and deltaL*=-1.03), indicating the effect of the color change was due to absorption. After fluoride varnish applications, Duraphat varnish produced significant changes in all tested materials and shades, resulting in color changes with deltaE greater than (>) 1 but less than (<) 3. These color changes are considered visually perceptible, yet have been reported in dental literature as clinically acceptable. Fluoride varnishes can be used without adversely affecting the color of restorative materials.  相似文献   
82.
Tuomilehto J  Hu G  Bidel S  Lindström J  Jousilahti P 《JAMA》2004,291(10):1213-1219
Context  Only a few studies of coffee consumption and diabetes mellitus (DM) have been reported, even though coffee is the most consumed beverage in the world. Objective  To determine the relationship between coffee consumption and the incidence of type 2 DM among Finnish individuals, who have the highest coffee consumption in the world. Design, Setting, and Participants  A prospective study from combined surveys conducted in 1982, 1987, and 1992 of 6974 Finnish men and 7655 women aged 35 to 64 years without history of stroke, coronary heart disease, or DM at baseline, with 175 682 person-years of follow-up. Coffee consumption and other study parameters were determined at baseline using standardized measurements. Main Outcome Measures  Hazard ratios (HRs) for the incidence of type 2 DM were estimated for different levels of daily coffee consumption. Results  During a mean follow-up of 12 years, there were 381 incident cases of type 2 DM. After adjustment for confounding factors (age, study year, body mass index, systolic blood pressure, education, occupational, commuting and leisure-time physical activity, alcohol and tea consumption, and smoking), the HRs of DM associated with the amount of coffee consumed daily (0-2, 3-4, 5-6, 7-9, =" BORDER="0">10 cups) were 1.00, 0.71 (95% confidence interval [CI], 0.48-1.05), 0.39 (95% CI, 0.25-0.60), 0.39 (95% CI, 0.20-0.74), and 0.21 (95% CI, 0.06-0.69) (P for trend<.001) in women, and 1.00, 0.73 (95% CI, 0.47-1.13), 0.70 (95% CI, 0.45-1.05), 0.67 (95% CI, 0.40-1.12), and 0.45 (95% CI, 0.25-0.81) (P for trend = .12) in men, respectively. In both sexes combined, the multivariate-adjusted inverse association was significant (P for trend <.001) and persisted when stratified by younger and older than 50 years; smokers and never smokers; healthy weight, overweight, and obese participants; alcohol drinker and nondrinker; and participants drinking filtered and nonfiltered coffee. Conclusion  Coffee drinking has a graded inverse association with the risk of type 2 DM; however, the reasons for this risk reduction associated with coffee remain unclear.   相似文献   
83.
84.
AIMS: There are only limited data comparing the diagnostic characteristics of carbohydrate-deficient transferrin (CDT) measurements in assays for excessive alcohol consumption under controlled conditions. METHODS: We compared different CDT assays and the conventional laboratory markers of ethanol consumption, gamma-glutamyl transferase (gamma-GT) aspartate aminotransferase (AST) and mean corpuscular volume (MCV) in the assessment and follow-up of 36 alcoholics (31 men, five women, mean age 44 years), who were admitted for detoxification. Detailed interviews to assess the amount of alcohol consumption were carried out for each patient. A hospital follow-up with supervised abstinence for 8 +/- 4 days (range 5-19 days) was carried out for 17 patients. Controls were 30 apparently healthy individuals (22 men, eight women, mean age 49 years), who had no history of hazardous drinking. RESULTS: At the time of admission, the %CDT method, which excludes the trisialotransferrin isoform from the measurement, yielded elevated values in 69% of the patients, compared to 61% for CDTect. The corresponding sensitivities for gamma-GT, AST and MCV were 61, 56 and 47%, respectively. The self-reported alcohol consumption for a period of 1 month prior to admission showed a stronger correlation with the %CDT results (r = 0.59, P = 0.0003) than with the CDTect results (r = 0.36, P = 0.04), GT (r = 0.40, P = 0.02) or AST (r = 0.35, P = 0.05). During follow-up with supervised abstinence the mean %CDT values were found to show a slower rate to normalization (mean 14 +/- 4 days) than the CDT values measured with the CDTect method (mean 10 +/- 5 days) (P < 0.05). CONCLUSIONS: The data indicate distinct differences and method-dependent rates of normalization in CDT assays, possibly reflecting different degrees of transferrin desialylation in the alcoholics. The present findings should be considered in studies on alcohol markers for monitoring abstinence.  相似文献   
85.
The pathophysiology of preeclampsia is incompletely understood, but the familial nature of the disease has long been recognized. Recent genome-scan studies have indicated linkage at the p23 region of chromosome 2. We have previously reported microsatellite marker association at chromosome region 2p13 in patients with obstetric cholestasis. We conducted population-based association screening with microsatellite markers to find potential preeclampsia-associated loci on chromosome region 2p13-p12 and to test whether preeclampsia and obstetric cholestasis share a single risk locus. The study was carried out among 115 unrelated control women, 133 preeclamptic women and 57 cholestatic women. Screening with microsatellite markers at the 2p13-p12 region revealed that the marker D2S286 was significantly associated with obstetric cholestasis in the overall association analysis (P=0.03), while it revealed only borderline association with preeclampsia (P=0.08). However, single allele association analysis indicated that both preeclampsia and obstetric cholestasis showed a statistically significant association with a common allele (P < 0.05), which was overrepresented in both the obstetric cholestasis (0.42) and preeclamptic (0.37) groups when compared with the control group (0.28). In conclusion, These findings suggest a possible genetic link between chromosome region 2p13-p12, preeclampsia and obstetric cholestasis. More specifically, these data suggest that there may be a common risk locus associated with both obstetric complications located in the vicinity of the 2p13-p12 association region.  相似文献   
86.
Pitfalls in detection of novel nanoorganisms   总被引:2,自引:0,他引:2  
  相似文献   
87.
OBJECTIVE: To determine whether genetic variability in the promoter regions of the genes encoding fibrinogen and factor VII contribute to individual differences in susceptibility to the development of preeclampsia. METHODS: The study involved 133 preeclamptic and 115 healthy control pregnant women who were genotyped for the G-455A polymorphism in the beta-fibrinogen gene promoter and for a decamer insertion or deletion polymorphism at position -323 in the factor VII gene promoter. We used chi(2) analysis to assess genotype frequency differences between preeclamptic women and controls. RESULTS: The allelic distribution of the fibrinogen A-455G polymorphism was similar in the two groups, with the frequency of the variant A allele being 18.8% in the preeclampsia group and 20.9% in the control group. We did not find any association between the presence of the factor VII insertion allele and preeclampsia (5.6% versus 6.1%). Accordingly, the genotype distribution of the fibrinogen G-455A and factor VII polymorphisms in the preeclamptic and control groups was similar (P =.852 and P =.308). CONCLUSION: The G-455A polymorphism of the fibrinogen gene promoter and the decamer insertion or deletion polymorphism of the factor VII gene promoter are unlikely to be major genetic predisposing factors for preeclampsia in subjects from eastern Finland.  相似文献   
88.
We evaluated the efficacy of cyclosporin A (CyA) for treating pediatric patients with severe Henoch-Schönlein glomerulonephritis (HSP-GN) and nephrotic-range proteinuria. Seven pediatric HSP-GN patients (5 boys, 2 girls) were treated with CyA, with a mean age of 10.6 years at diagnosis (range 7.2–15.2 years) and mean follow-up times of 6.0 years (range 4.4–8.9 years) from diagnosis and 5.2 years (range 3.4–7.7 years) from the beginning of the CyA treatment. All had developed nephrotic-range proteinuria within 1–3 months of the HSP diagnosis. A renal biopsy was performed on all the patients, and two showed rapidly progressive glomerulonephritis. They all received additional angiotensin converting enzyme inhibitor medication and one to three types of immunosuppressive treatment had been tried in five of the seven patients before CyA was initiated at a mean interval of 0.7 years after diagnosis (range 0.1–2.0 years). All the patients responded to the CyA treatment within a mean of 1.4 months (range 1 week to 4 months). Four patients achieved a stable remission and had been without CyA treatment for a mean of 3.7 years (range 2.9–5.3 years) by the end of the follow-up. Three patients seemed to become CyA dependent, since they developed proteinuria when the treatment was stopped. CyA treatment had been started significantly earlier (P=0.045) in the former group (mean 0.2 years, range 0.1–0.3 years) than in the latter (mean 1.5 years, range 1.2–2.0 years). Renal function was preserved in all patients, the glomerular filtration rate, plasma cystatin C, serum albumin, and serum creatinine being within normal limits at the end of the follow-up. We conclude that CyA treatment for severe treatment-resistant HSP-GN is promising, since four of the seven patients enjoy stable remission and all have retained their renal function after a mean follow-up of 6.0 years. However, some patients seem to develop CyA-dependent nephritis.The results were presented as a poster at the 36th meeting of the European Society for Pediatric Nephrology in Bilbao  相似文献   
89.
AIMS: Due to methodological heterogeneity, conflicting views have been expressed on the validity of CDT measurements in the detection of alcohol misuse. METHODS: We compared the characteristics of the conventional CDTect method and the Axis turbidimetric CDT assays in the assessment of 62 alcoholics, who were either with (n = 33) or without (n = 29) liver disease, as analysed by combined clinical, laboratory, and morphological indices. Controls were 45 healthy volunteers who were either social drinkers or abstainers. RESULTS: In the total sample of alcoholics, the sensitivity of the %CDT method, which excludes the trisialotransferrin isoform from the measurement, was 63% for men and 46% for women, as compared to 65% and 36% of CDTect, respectively. Both of these methods showed higher sensitivities than the %CDT-TIA method, which reacts with trisialotransferrin (32% and 25%, respectively). The assay specificities were 100% for men and 91% for women with %CDT, and 96% and 87% with the CDTect, respectively. The correlation between the CDTect and %CDT method was higher in men (r = 0.86) than in women (r = 0.57). The presence of liver disease was found to influence the results of the CDTect method, such that the highest CDT concentrations were observed in patients with mild to moderate liver disease, especially among women, whereas the %CDT method was less sensitive to the effect of liver pathology. The self-reported alcohol consumption from the 4 weeks prior to sampling showed a higher correlation between the %CDT results (r = 0.64, P < 0.0001) than with the CDTect results (r = 0.40; P < 0.01). CONCLUSIONS: The data indicate that the new %CDT method offers advantages over the previous versions of the CDT methods. The improved characteristics may be most useful in assays for excessive alcohol consumption in female alcoholics, patients with liver disease, and in patients with abnormal serum transferrin concentrations.  相似文献   
90.
BACKGROUND: Physical inactivity is related to an increased risk of certain chronic diseases. The aim here was to evaluate how physical activity and social status in adolescence are associated with physical inactivity in adulthood. METHODS: The sample comprised 3664 males and 4130 females who answered questions on physical activity and social status at 14 and 31 years of age in follow-up surveys of the Northern Finland birth cohort of 1966. Associations between explanatory factors and physical inactivity in adulthood were analyzed using multivariable logistic regression. RESULTS: Infrequent participation in sports after school hours at 14 years of age and, in males, additionally a low grade in school sports, was associated with physical inactivity at the age of 31 years, independent of social circumstances in adulthood. Low social class of the childhood family was associated with physical inactivity in adolescence but not with inactivity at 31 years of age. Poor school achievement in adolescence was associated with adult inactivity independent of adolescent physical activity. CONCLUSION: Infrequent participation in sports, a low grade in school sports, and poor school achievements in adolescence were associated with physical inactivity in adulthood. Participation in sports is to be strongly supported among all adolescents because of its long-term beneficial effects on adult health through its tendency to reduce the probability of adult inactivity.  相似文献   
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