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1.
BackgroundThe authors of this practice-based study estimated the risk of experiencing tooth fractures and crack progression over 3 years and correlated baseline patient-, tooth-, and crack-level characteristics with these outcomes.MethodsTwo-hundred-and-nine National Dental Practice-Based Research Network dentists enrolled a convenience sample of 2,601 participants with a cracked vital posterior tooth that had been examined for at least 1 recall visit over 3 years. Data were collected at the patient, tooth, and crack levels at baseline, annual follow-up visits, and any interim visits. Associations between these characteristics and the subsequent same-tooth fractures and crack progression were quantified.ResultsOf the 2,601 teeth with a crack or cracks at baseline, 78 (3.0%; 95% confidence interval, 2.4% to 3.7%) subsequently developed a fracture. Of the 1,889 patients untreated before year 1, 232 (12.3%; 95% confidence interval, 10.9% to 13.8%) had some type of crack progression. Baseline tooth-level characteristics associated with tooth fracture were the tooth was maxillary and had a wear facet through enamel and a crack was detectable with an explorer, on the facial surface, and in a horizontal direction. Crack progression was associated with males and teeth with multiple cracks at baseline; teeth with a baseline facial crack were less likely to show crack progression. There was no commonality between characteristics associated with tooth fracture and those associated with crack progression.ConclusionsDevelopment of tooth fractures and crack progression over 3 years were rare occurrences. Specific characteristics were associated with the development of tooth fracture and crack progression, although none were common to both.Practical ImplicationsThis information can aid dentists in assessing factors that place posterior cracked teeth at risk of experiencing adverse outcomes.  相似文献   
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Much of the structural stability of the nucleus comes from meshworks of intermediate filament proteins known as lamins forming the inner layer of the nuclear envelope called the nuclear lamina. These lamin meshworks additionally play a role in gene expression. Abnormalities in nuclear shape are associated with a variety of pathologies, including some forms of cancer and Hutchinson–Gilford Progeria Syndrome, and often include protruding structures termed nuclear blebs. These nuclear blebs are thought to be related to pathological gene expression; however, little is known about how and why blebs form. We have developed a minimal continuum elastic model of a lamin meshwork that we use to investigate which aspects of the meshwork could be responsible for bleb formation. Mammalian lamin meshworks consist of two types of lamin proteins, A type and B type, and it has been reported that nuclear blebs are enriched in A-type lamins. Our model treats each lamin type separately and thus, can assign them different properties. Nuclear blebs have been reported to be located in regions where the fibers in the lamin meshwork have a greater separation, and we find that this greater separation of fibers is an essential characteristic for generating nuclear blebs. The model produces structures with comparable morphologies and distributions of lamin types as real pathological nuclei. Thus, preventing this opening of the meshwork could be a route to prevent bleb formation, which could be used as a potential therapy for the pathologies associated with nuclear blebs.  相似文献   
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New antiretroviral (ARV) regimens require strict adherence if optimal suppression of HIV is to be maintained. This study is a theory-based examination of racial differences in patient-perceived barriers and reported ARV adherence. Participants (N=149) completed the Patient Medication Adherence Questionnaire (PMAQ), measuring adherence and perceived barriers to adherence. Adherence was defined as a self-report of 100% adherence in the past four weeks. Odds ratios were calculated to determine the relation of reported barriers to adherence for race and gender groups, and for the sample overall. For every ten-point increase in barrier score, there was an 86% increased risk of being non-adherent (OR=1.86; 95% CI: 1.19, 2.91). Adherence was not different between racial and gender groups, nor was total barrier score. However, individual barriers were differentially endorsed across groups. Rather than relying on demographic predictors, which may be only an indirect marker of adherence, evaluations of adherence should examine the psychological and social barriers to positive adherence outcomes in individual patients. Our findings support the use of theory-based behavioural interventions that address perceived barriers to adherence and other health promotion activities.  相似文献   
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STUDY OBJECTIVES: Patients in a pulmonary clinic have disorders that predispose them to osteoporosis and may use glucocorticoid therapy, which has been associated with low bone mineral density (BMD) and increased fracture risk. Ideally, all patients at risk for osteoporosis would be screened using the best test available, which is central BMD by dual-energy x-ray absorptiometry (DXA). We proposed to stratify the risk for osteoporosis by the use of a simple questionnaire and point-of-care heel ultrasound BMD measurements. DESIGN: Cross-sectional screening study. SETTING: Pulmonary clinic in a single Veterans Affairs Medical Center. PATIENTS: Approximately 200 male and female patients who had not had previous BMD testing were eligible for the study, and 107 gave consent. INTERVENTIONS: One hundred seven men (white, 71 men; black, 35 men; and Asian, 1 man) underwent heel BMD testing and filled out a questionnaire. Ninety-eight men underwent a central DXA. RESULTS: Of 98 subjects, 24.5% had a spine, total hip, or femoral neck (FN) T-score of or= 7 days, and race, which accounted for 52 to 57% of the variance. When a heel ultrasound T-score of -1.0 was tested to predict a central DXA T-score of -2.0, the sensitivity was 61% and the specificity 64%. Adding the questionnaire score and body mass index (BMI) to the heel T-score improved sensitivity but not specificity. Moreover, BMI and age predicted central BMD with similar sensitivity and specificity. Importantly, of 24 patients with a central DXA T-score of 相似文献   
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Purpose: Given the strong association of stroke and epilepsy in older persons, and the existence of a Stroke Belt in the United States, we hypothesized that geographic variation in epilepsy prevalence would follow geographic patterns similar to stroke. Methods: We used a 2005 5% random sample of Medicare beneficiaries 65 and older in 48 U.S. contiguous states. Epilepsy was identified from claims for physician visits, hospitalizations, and outpatient procedures. Prevalence was obtained by state and county. Logistic regressions determined the independent association of the likelihood of epilepsy (prevalent or new case) and residence in Stroke Belt states, controlling for residence in highest epilepsy prevalence states, demographics (race, age, gender), comorbid conditions, cerebrovascular disease, dementia, and county characteristics. Key Findings: Of 1,212,015 beneficiaries, 11.9 per 1,000 had prevalent and 2.9 new cases of epilepsy. Nine of 11 Stroke Belt states were among the 20 states with the highest epilepsy prevalence. Counties in the 10 highest epilepsy prevalence states were more likely to be large urban counties with a higher number of neurologists or neurosurgeons per capita. The higher likelihood of prevalent epilepsy cases associated with Stroke Belt residence was explained by beneficiaries’ race; that associated with residence in high epilepsy prevalence states was not. The likelihood of new epilepsy cases was negatively associated with Stroke Belt residence when controlling for covariates. Significance: The geographic variation in epilepsy prevalence is not explained by variations in known risk factors. Further research should investigate why eastern U.S. states have higher frequency of epilepsy.  相似文献   
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This study was conducted to investigate the effect of Plasmodium falciparum and intestinal helminth coinfection on maternal anemia and birth outcomes. A cross-sectional study of 746 women who delivered in two hospitals in Kumasi was conducted. Data were collected using an investigator-administered questionnaire and from patients'' medical records. Blood was collected for determination of P. falciparum and hemoglobin levels. Adverse pregnancy outcomes were high (44.6%). Coinfection (versus no infection) was associated with 3-fold increase in low birth weight. For women with anemia, coinfection was 2.6 times and 3.5 times as likely to result in preterm deliveries and small for gestational age infants. The odds of having anemia was increased almost 3-fold by coinfection. Coinfection (versus helminth only) resulted in increased risks of anemia, low birth weight, and small for gestational age infants. This study demonstrates that women with malaria and intestinal helminth coinfection are at particular risk of adverse birth outcomes.  相似文献   
8.

Objective  

Recent reports have linked oral health and periodontal disease indicators with increased risk of squamous cell carcinoma of head and neck (SCCHN). Thus far, evidence has been inconclusive; our objective was to study the association between oral health and SCCHN risk in the context of a large population-based study.  相似文献   
9.
Chronic inflammation has been implicated in the development of epithelial ovarian cancer (EOC); yet the contribution of inflammatory foods and nutrients to EOC risk has been understudied. We investigated the association between the dietary inflammatory index (DII), a novel literature‐derived tool to assess the inflammatory potential of one's diet, and EOC risk in African American (AA) women in the African American Cancer Epidemiology Study, the largest population‐based case–control study of EOC in AA women to date. The energy‐adjusted DII (E‐DII) was computed per 1,000 kilocalories from dietary intake data collected through a food frequency questionnaire, which measured usual dietary intake in the year prior to diagnosis for cases or interview for controls. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were estimated using multivariable logistic regression for the association between the E‐DII and EOC risk. 493 cases and 662 controls were included in the analyses. We observed a 10% increase in EOC risk per a one‐unit change in the E‐DII (OR = 1.10, 95% CI = 1.03–1.17). Similarly, women consuming the most pro‐inflammatory diet had a statistically significant increased EOC risk in comparison to the most anti‐inflammatory diet (ORQuartile4/Quartile1 = 1.72; 95% CI = 1.18–2.51). We also observed effect modification by age (p < 0.05), where a strong, significant association between the E‐DII and EOC risk was observed among women older than 60 years, but no association was observed in women aged 60 years or younger. Our findings suggest that a more pro‐inflammatory diet was associated with an increased EOC risk, especially among women older than 60 years.  相似文献   
10.
Two visual field indices, the mean defect (MD) of Flammer and the mean deviation (MD) of Heijl, have found wide acceptance among perimetrists. We compared these indices in 169 visual fields from normal- and high-tension glaucomatous eyes. Visual field damage in these eyes varied from slight to severe. In computations of the mean deviation index, the threshold values are weighted by the threshold deviations obtained from normal eyes as a function of eccentricity. However, the present study shows that the differences between the two indices in the population studied are negligible. Thus, subsequent interpretation is not affected by the choice of index, and the two MD indices may be considered to be interchangeable for the types of visual fields used in this study and for program-G1 examinations carried out using Octopus automated perimeters. Since we found smaller increases in local intersubjective fluctuations as a function of eccentricity in 274 normal visual fields as compared with results published by others, caution is indicated for interpretation of the visual field using probability weighting.The authors have no proprietary interests in the equipment or companies referred to in this paper Offprint requests to: A.T. Funkhouser  相似文献   
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