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排序方式: 共有1646条查询结果,搜索用时 15 毫秒
81.
Yaling Han Guoying Zhu Lixian Han Fengxia Hou Weijian Huang Huiliang Liu Jihong Gan Tiemin Jiang Xiaoyan Li Wei Wang Shifang Ding Shaobin Jia Weifeng Shen Dongmei Wang Ling Sun Jian Qiu Xiaozeng Wang Yi Li Jie Deng Jing Li Kai Xu Bo Xu Roxana Mehran Yong Huo 《Journal of the American College of Cardiology》2014
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Lisa M. McKenzie Ruixin Guo Roxana Z. Witter David A. Savitz Lee S. Newman John L. Adgate 《Environmental health perspectives》2014,122(4):412-417
Background: Birth defects are a leading cause of neonatal mortality. Natural gas development (NGD) emits several potential teratogens, and U.S. production of natural gas is expanding.Objectives: We examined associations between maternal residential proximity to NGD and birth outcomes in a retrospective cohort study of 124,842 births between 1996 and 2009 in rural Colorado.Methods: We calculated inverse distance weighted natural gas well counts within a 10-mile radius of maternal residence to estimate maternal exposure to NGD. Logistic regression, adjusted for maternal and infant covariates, was used to estimate associations with exposure tertiles for congenital heart defects (CHDs), neural tube defects (NTDs), oral clefts, preterm birth, and term low birth weight. The association with term birth weight was investigated using multiple linear regression.Results: Prevalence of CHDs increased with exposure tertile, with an odds ratio (OR) of 1.3 for the highest tertile (95% CI: 1.2, 1.5); NTD prevalence was associated with the highest tertile of exposure (OR = 2.0; 95% CI: 1.0, 3.9, based on 59 cases), compared with the absence of any gas wells within a 10-mile radius. Exposure was negatively associated with preterm birth and positively associated with fetal growth, although the magnitude of association was small. No association was found between exposure and oral clefts.Conclusions: In this large cohort, we observed an association between density and proximity of natural gas wells within a 10-mile radius of maternal residence and prevalence of CHDs and possibly NTDs. Greater specificity in exposure estimates is needed to further explore these associations.Citation: McKenzie LM, Guo R, Witter RZ, Savitz DA, Newman LS, Adgate JL. 2014. Birth outcomes and maternal residential proximity to natural gas development in rural Colorado. Environ Health Perspect 122:412–417; http://dx.doi.org/10.1289/ehp.1306722 相似文献
84.
Veronica Anstsoaie Roxana Tomescu Cristian Kusko Iuliana Mihalache Adrian Dinescu Catalin Parvulescu Gabriel Craciun Stefan Caramizoiu Dana Cristea 《Materials》2022,15(4)
One of the strategies employed to increase the sensitivity of the fluorescence-based biosensors is to deposit chromophores on plasmonic metasurfaces which are periodic arrays of resonating nano-antennas that allow the control of the electromagnetic field leading to fluorescence enhancement. While artificially engineered metasurfaces realized by micro/nano-fabrication techniques lead to a precise tailoring of the excitation field and resonant cavity properties, the technological overhead, small areas, and high manufacturing cost renders them unsuitable for mass production. A method to circumvent these challenges is to use random distribution of metallic nanoparticles sustaining plasmonic resonances, which present the properties required to significantly enhance the fluorescence. We investigate metasurfaces composed of random aggregates of metal nanoparticles deposited on a silicon and glass substrates. The finite difference time domain simulations of the interaction of the incident electromagnetic wave with the structures reveals a significant enhancement of the excitation field, which is due to the resonant plasmonic modes sustained by the nanoparticles aggregates. We experimentally investigated the role of these structures in the fluorescent behaviour of Rhodamine 6G dispersed in polymethylmethacrylate finding an enhancement that is 423-fold. This suggests that nanoparticle aggregates have the potential to constitute a suitable platform for low-cost, mass-produced fluorescent biosensors. 相似文献
85.
Ulrike Maria Dauter Ayman Alhamdow Andrea Cediel-Ulloa Anda Roxana Gliga Maria Albin Karin Broberg 《Scandinavian journal of work, environment & health》2022,48(1):21
ObjectiveThis study tested for an association between early cancer-related biomarkers and low-to-moderate exposure to fumes from welding mild steel.MethodsMale, non-smoking participants from southern Sweden were recruited and examined (N=338, 171 welders and 167 controls); of these, 78 welders and 96 controls were examined on two occasions six years apart. Exposure to welding fumes was evaluated by measuring respirable dust, welding years, and cumulative exposure. DNA methylation of CpG sites within the cancer-related genes AHRR, F2RL3, and B3GNTL1 was measured by pyrosequencing and relative mitochondrial DNA copy number and telomere length were measured by qPCR in whole-blood samples. Multivariate models were used for longitudinal analysis.ResultsMedian exposure to respirable dust was 0.7 mg/m3 at both timepoints, adjusted for use of personal protective equipment. Compared with controls, welders showed a significant decrease over time in DNA methylation of B3GNTL1 CpG1 and CpG4 [adjusted for age, body mass index, and smoking: β=-0.66, standard error (SE)=0.28; β=-0.48, SE=0.24, respectively]. In addition, exposure to respirable dust and cumulative exposure was associated with a decrease in methylation of F2RL3 CpG2 among all welders (adjusted β=-0.67, SE=0.23 and β=-0.03, SE=0.02, respectively). No significant associations were found for AHRR, mitochondrial DNA copy number, or telomere length.ConclusionLow-to-moderate exposure to welding fumes was associated with a small effect on selected early epigenetic biomarkers of cancer. The direction of the methylation pattern (lower methylation of specific CpG sites) indicates early lung cancer-related changes associated with mild steel welding. 相似文献
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Leiva E Mujica V Orrego R Prieto M Arredondo M 《Diabetes research and clinical practice》2005,68(3):244-249
Apolipoprotein E (apo E) modulates the metabolism of atherogenic lipoprotein particles and participates in the process of cellular incorporation of specific lipoproteins. Genetic polymorphism of apo E has been reported as an important dyslipidemia genetic marker associated with coronary artery disease. Type 2 diabetes mellitus is a disease with a high incidence and prevalence in the world. The main cause of death in these patients is myocardial stroke and a high incidence of general cardiovascular complications. The purpose of this work was to characterize the genotype of apo E in diabetic patients from Talca, Chile, in order to describe the allelic frequency of the apo E gene and its correlation to the lipids profile. Type 2 diabetic patients (200) were recruited from the Diabetes Program of Talca Hospital, Chile. Apo E genotype was determined by restriction fragment-length polymorphism analysis. A biochemical characterization was performed in all the subjects. Type 2 diabetic patients had elevated levels of glycemia, lipid profile and BMI compared to the control group. The E3/3 genotype and epsilon3 allele had a higher frequency in both groups. The E2/3 and E3/4 genotypes had higher levels of triglyceride (TG) and cholesterol respectively; however, there was not any statistical relationship between them. In conclusion, genotype of apo E in diabetic patients did not differ with healthy; E2/3 and E3/4 genotypes tend to have higher levels of triglyceride and cholesterol respectively. We think that these results corroborate that in the etiology of the dyslipidemia, there is more than one associate genetic marker. 相似文献
89.
Adriano Caixeta MD PhD Martin B. Leon MD Alexandra J. Lansky MD Eugenia Nikolsky MD PhD Jiro Aoki MD PhD Jeffrey W. Moses MD Joachim Schofer MD Marie-Claude Morice MD Erick Schampaert MD Ajay J. Kirtane MD SM Jeffrey J. Popma MD Helen Parise DSc Martin Fahy MSc Roxana Mehran MD 《Journal of the American College of Cardiology》2009,54(10):894-902
90.
Gill Louise Buchanan Alaide Chieffo Emanuele Meliga Roxana Mehran Seung-Jung Park Yoshinobu Onuma Piera Capranzano Marco Valgimigli Inga Narbute Raj R. Makkar Igor F. Palacios Young-Hak Kim Piotr P. Buszman Tarun Chakravarty Imad Sheiban Christoph Naber Ronan Margey Arvind Agnihotri Sebastiano Marra Davide Capodanno Victoria Allgar Martin B. Leon Jeffrey W. Moses Jean Fajadet Thierry Lefevre Marie-Claude Morice Andrejs Erglis Corrado Tamburino Ottavio Alfieri Patrick W. Serruys Antonio Colombo 《The American journal of cardiology》2014