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STUDY OBJECTIVES: This study examines long-term trends in incidence rates of hospitalized pulmonary sarcoidosis in a large cohort of Navy personnel, and evaluates the possible relationship of sarcoidosis with occupation. DESIGN: Incidence rates of first hospitalizations were determined for black and white male Navy enlisted personnel on active duty from 1975 to 2001. SETTING: Navy service includes a potential for exposure to a variety of substances, including nonskid coatings used on ship decks that may be aerosolized during removal. Particulate matter containing aluminum, titanium, and silicates has been identified in nonskid samples. Specific occupational groups may have had greater exposure potential than others. PATIENTS OR PARTICIPANTS: Hospitalized cases included sarcoidosis (n = 674), asthma (n = 3,536), emphysema and chronic bronchitis (n = 1,103), respiratory conditions due to fumes and vapors (n = 61), and pneumoconiosis (n = 51) observed in 9,953,607 person-years of active-duty service. INTERVENTIONS: None. However, improvements were made in personal protective gear and other countermeasures to prevent or limit respiratory exposures during service. MEASUREMENTS AND RESULTS: Annual overall hospitalized sarcoidosis incidence rates per 100,000 were 24.9 for black men and 3.5 for white men (black/white ratio of 7.1, p < 0.0001). Annual incidence rates in blacks declined markedly, particularly since 1989, but the black/white ratio remained high through 1999. Occupational associations were present in blacks and whites. Black ship's servicemen (23 cases) and aviation structural mechanics specializing in structures (12 cases) had more than twice the expected incidence rate compared to all blacks, and white mess management specialists (15 cases) had twice the overall white incidence rate. CONCLUSIONS: There was a steep decline in incidence of hospitalized sarcoidosis in blacks in the Navy. Occupational associations suggest the possibility that a dust or moisture-related lung disease may have been erroneously classified as sarcoidosis, or, alternatively, that sarcoidosis had a previously unrecognized occupational component. 相似文献
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Accuracy of multislice computed tomography in the preoperative assessment of coronary disease in patients with aortic valve stenosis. 总被引:4,自引:0,他引:4
Martine Gilard Jean-Christophe Cornily Pierre-Yves Pennec Cedric Joret Grégoire Le Gal Jacques Mansourati Jean-Jacques Blanc Jacques Boschat 《Journal of the American College of Cardiology》2006,47(10):2020-2024
OBJECTIVES: To evaluate multislice computed tomography (MSCT) as an alternative to coronary angiography, we prospectively studied its diagnostic accuracy for the detection of significant coronary artery lesions in patients with significant aortic valve stenosis undergoing valve surgery. BACKGROUND: In patients with aortic valve stenosis, coronary angiography is still recommended before surgery. Multislice computed tomography is a promising noninvasive technique for the detection of significant coronary artery lesions. METHODS: Fifty-five consecutive patients scheduled for coronary angiography in the preoperative assessment of aortic valve stenosis underwent 16-slice MSCT 24 h before coronary angiography. We analyzed coronary lesions, image quality, and arterial calcium score. RESULTS: The sensitivity of the MSCT-based strategy in detecting significant stenosis was 100%, and its specificity 80%. The positive and negative predictive values were respectively 55% and 100%. For calcium scores <1,000 (77% of patients), MSCT detected all patients without coronary artery disease, enabling conventional coronary angiography to be avoided in 35 of 55 cases (80%). For calcium scores >1,000, MSCT enabled conventional coronary angiography to be avoided in only 6% of cases, either because significant stenosis was found with a possible indication of revascularization, or because the examination was not interpretable. CONCLUSIONS: The results of this initial experience in relatively few patients suggest that MSCT-based coronary angiography may serve as an alternative to invasive coronary angiography to rule out significant coronary artery disease in patients scheduled for elective aortic valve replacement. Larger studies are necessary to fully explore the potential of coronary MSCT to improve preoperative risk stratification. 相似文献
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Stacie Nguyen Leo Baggerly Christine French Robert P. Heaney Edward D. Gorham Cedric F. Garland 《American journal of public health》2014,104(9):1783-1787
Objectives. Increasing 25-hydroxyvitamin D serum levels can prevent a wide range of diseases. There is a concern about increasing kidney stone risk with vitamin D supplementation. We used GrassrootsHealth data to examine the relationship between vitamin D status and kidney stone incidence.Methods. The study included 2012 participants followed prospectively for a median of 19 months. Thirteen individuals self-reported kidney stones during the study period. Multivariate logistic regression was applied to assess the association between vitamin D status and kidney stones.Results. We found no statistically significant association between serum 25-hydroxyvitamin D and kidney stones (P = .42). Body mass index was significantly associated with kidney stone risk (odds ratio = 3.5; 95% confidence interval = 1.1, 11.3).Conclusions. We concluded that a serum 25-hydroxyvitamin D level of 20 to 100 nanograms per milliliter has no significant association with kidney stone incidence.An issue of possible concern related to the use of vitamin D supplementation is a reported increase in risk of kidney stones.1 Mounting evidence indicates that a 25-hydroxyvitamin D (25[OH]D) serum level in the range of 40 to 60 nanograms per milliliter (ng/mL) is needed for substantial reduction in risk of a wide range of diseases including breast cancer,2 colorectal cancer,3 multiple sclerosis,4 and type 1 diabetes.5,6 However, few people can achieve 25(OH)D in the range higher than 40 ng/mL without supplementation.7GrassrootsHealth is a nonprofit public health research organization that runs a large population cohort study of participants who reach and sustain, if desired, a 25(OH)D serum level of their choice and tracking subsequent health outcomes. GrassrootsHealth has assembled a database that includes information on serum 25(OH)D concentrations, demographic characteristics, and health status measures. These data include values from 5552 individuals with daily supplemental intakes averaging 3600 international units (IU) per day and an average 25(OH)D level of 45 ng/mL, which is higher than the ranges found in most other cohorts.2,4In this study we investigated whether serum 25(OH)D concentration in the range of 20 to 100 ng/mL was associated with incidence of kidney stones in all participants who provided data at 2 or more sampling times. 相似文献
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Cedric Hurth Jianing Yang Matthew Barrett Carla Brooks Alan Nordquist Stanley Smith Frederic Zenhausern 《Biomedical microdevices》2014,16(6):905-914
We report a microfluidic device and measurement method to perform real-time PCR (or qPCR) in a miniaturized configuration for on-chip implementation using reaction volumes of less than 20 μL. The qPCR bioreactor is designed as a module to be embedded in an automated sample-in/profile-out system for rapid DNA biometrics or human identification. The PCR mixture is excited with a 505 nm diode-pumped solid-state laser (DPSSL) and the fluorescence build-up is measured using optical fibers directly embedded to the sidewalls of the microfluidic qPCR bioreactor. We discuss manufacturing and operating parameters necessary to adjust the internal surface conditions and temperature profiles of the bioreactor and to optimize the yield and quality of the PCR reaction for the amplification of 62 bp hTERT intron fragments using the commercial Quantifiler® kit (Life Technologies, Carlsbad, CA) commonly accepted for genotyping analysis. We designed a microfluidic device suitable for continuously processing a specimen by efficiently mixing the reagents from the kit to a set volume of DNA template on chip. Our approach relies on a calibration curve for the specific device using control DNA. We successfully applied this method to determine the concentration of genomic DNA extracted from a buccal swab on separate microfluidic devices which are operated upstream the qPCR device and perform buccal swab lysis and buccal DNA extraction. A precise correlation between the amount determined on chip and that obtained using a commercial cycler is demonstrated. 相似文献
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