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排序方式: 共有620条查询结果,搜索用时 78 毫秒
101.
Pauliina Taimisto Marko Tainio Niko Karvosenoja Kaarle Kupiainen Petri Porvari Ari Karppinen Leena Kangas Jaakko Kukkonen Jouni T. Tuomisto 《Air quality, atmosphere, & health》2011,4(3-4):199-209
Domestic wood combustion and traffic are the two most significant primary fine particulate matter (PM2.5) emission source categories in Finland. We estimated emission–exposure relationships for primary PM2.5 emissions from these source categories using intake fractions (iF), which describes the fraction of an emission that is ultimately inhaled by a target population. The iFs were calculated for four different emission source subcategories in Finland in 2000: (1) domestic wood combustion in residential buildings, (2) domestic wood combustion in recreational buildings, (3) traffic exhaust and wear emissions, and (4) traffic resuspension emissions. The iFs were estimated for both total population and for subpopulations with different gender, age, and educational status. Primary PM2.5 emissions were based on the Finnish Regional Emission Scenario model and the dispersion of particles was calculated using the Urban Dispersion Modeling system of Finnish Meteorological Institute. Both emissions and dispersion were estimated on a 1 km spatial resolution. The iFs for primary PM2.5 emissions from (1) residential and (2) recreational buildings were 3.4 and 0.6 per million, respectively. The corresponding iF for (3) traffic exhaust and wear and (4) traffic resuspension emissions were 9.7 and 9.5 per million, respectively. The differences in population-weighted outdoor concentrations were significant between subpopulations with different educational status so that people with higher education were exposed more to traffic-related PM2.5. 相似文献
102.
Offenbächer M Sauer S Hieblinger R Hufford DJ Walach H Kohls N 《Disability and rehabilitation》2011,33(25-26):2434-2445
103.
Iman El-Hariry Thomas Powles Mike R. Lau Cora N. Sternberg Alain Ravaud Hans von der Maase Niko Zantl Peter Harper Frédéric Rolland Bruno Audhuy Friederike Barthel Jean-Pascal Machiels Pina Patel Ernst-Dietrick Kreuser Robert E. Hawkins 《European journal of cancer (Oxford, England : 1990)》2010,46(5):859-862
Expression of epidermal growth factor receptor (EGFR) may be of prognostic value in renal cell cancer (RCC). Gene amplification of EGFR was investigated in a cohort of 315 patients with advanced RCC from a previously reported randomised study. Using fluorescent in situ hybridisation, only 2 patients (0.6%) had gene amplification; therefore gene amplification is of no prognostic value in RCC. 相似文献
104.
Tiffany G. Munzer Alison L. Miller Holly E. Brophy-Herb Karen E. Peterson Mildred A. Horodynski Dawn Contreras Julie Sturza Niko Kaciroti Julie C. Lumeng 《Academic pediatrics》2018,18(4):452-459
Objective
Assessment of pediatric behavior problems often requires rating scales from multiple reporters in different settings (eg, home and school); however, concordance between reporters may be low. Pediatricians must reconcile differences to inform treatment. We sought to examine characteristics predicting parent–teacher concordance on ratings of preschoolers' behavior problems.Methods
Data from 562 preschoolers were used from the Growing Healthy study, an obesity prevention trial in Head Start programs (2011–2015). Parents and teachers completed the Eyberg Child Behavior Inventory (ECBI)/Student Behavior Inventory (SBI) and the Social Competence and Behavior–Evaluation (SCBE). Outcome variables were: parent–teacher concordance (teacher minus parent score on each subscale of ECBI/SBI and SCBE); teacher reports problem behavior, parent does not (children rated in the top quintile of challenging behavior by teacher but not parent); and parent reports problem behavior, teacher does not (children rated in the top quintile of challenging behavior by parent but not teacher). Multiple linear and logistic regression models were created for each subscale outcome, including the following covariates: child sex, child race/ethnicity, parent age, parent education, family structure, parent depressive symptoms, and parenting self-efficacy, and time of school year.Results
Lower concordance was associated with child female sex, and child black or Hispanic race/ethnicity; parent older age, lower education, more depressive symptoms, and greater self-efficacy; and beginning of school year.Conclusions
Low parent–teacher concordance may reflect different perceptions of child behavior. Pediatricians could consider parent depressive symptoms, culture, and implicit bias when interpreting differences in behavior ratings by parents and teachers. 相似文献105.
Franko A Dolzan V Arnerić N Dodic-Fikfak M 《Journal of occupational and environmental medicine / American College of Occupational and Environmental Medicine》2008,50(1):7-12
OBJECTIVE: Genetic factors play an important role in the development of asbestosis. The aim of this study was to investigate whether genetic polymorphisms of glutathione S-transferase (GST) P1 represent a risk factor for this disease. METHODS: The study population included 262 workers with asbestosis and 265 matched controls. Information on cumulative asbestos exposure was available. A real-time PCR based on the 5' nuclease assay was designed for the analysis of GSTP1 Ile105Val and Ala114Val polymorphisms. RESULTS: Asbestosis was associated with GSTP1 genotype coding for an enzyme with high conjugation capacity versus genotypes resulting in intermediate and low enzyme activity (odds ratio = 1.49, confidence interval = 1.06-2.10). CONCLUSIONS: The key finding of the study was that GSTP1 genotype coding for an enzyme with high conjugation capacity significantly increases the risk of developing asbestosis. 相似文献
106.
107.
Comparison of composite prostate radiotherapy plan doses with dependent and independent boost phases
Ganesh Narayanasamy Gabrielle Avila Panayiotis Mavroidis Niko Papanikolaou Alonso Gutierrez Diana Baacke Zheng Shi Sotirios Stathakis 《Australasian physical & engineering sciences in medicine / supported by the Australasian College of Physical Scientists in Medicine and the Australasian Association of Physical Sciences in Medicine》2016,39(3):727-733
Prostate cases commonly consist of dual phase planning with a primary plan followed by a boost. Traditionally, the boost phase is planned independently from the primary plan with the risk of generating hot or cold spots in the composite plan. Alternatively, boost phase can be planned taking into account the primary dose. The aim of this study was to compare the composite plans from independently and dependently planned boosts using dosimetric and radiobiological metrics. Ten consecutive prostate patients previously treated at our institution were used to conduct this study on the Raystation? 4.0 treatment planning system. For each patient, two composite plans were developed: a primary plan with an independently planned boost and a primary plan with a dependently planned boost phase. The primary plan was prescribed to 54 Gy in 30 fractions to the primary planning target volume (PTV1) which includes prostate and seminal vesicles, while the boost phases were prescribed to 24 Gy in 12 fractions to the boost planning target volume (PTV2) that targets only the prostate. PTV coverage, max dose, median dose, target conformity, dose homogeneity, dose to OARs, and probabilities of benefit, injury, and complication-free tumor control (P+) were compared. Statistical significance was tested using either a 2-tailed Student’s t-test or Wilcoxon signed-rank test. Dosimetrically, the composite plan with dependent boost phase exhibited smaller hotspots, lower maximum dose to the target without any significant change to normal tissue dose. Radiobiologically, for all but one patient, the percent difference in the P+ values between the two methods was not significant. A large percent difference in P+ value could be attributed to an inferior primary plan. The benefits of considering the dose in primary plan while planning the boost is not significant unless a poor primary plan was achieved. 相似文献
108.
109.
Swapnali Pathare Alejandro A. Schäffer Niko Beerenwinkel Manoj Mahimkar 《International journal of cancer. Journal international du cancer》2009,124(12):2864-2871
Oral cancer develops and progresses by accumulation of genetic alterations. The interrelationship between these alterations and their sequence of occurrence in oral cancers has not been thoroughly understood. In the present study, we applied oncogenetic tree models to comparative genomic hybridization (CGH) data of 97 primary oral cancers to identify pathways of progression. CGH revealed the most frequent gains on chromosomes 8q (72.4%) and 9q (41.2%) and frequent losses on 3p (49.5%) and 8p (47.5%). Both mixture and distance‐based tree models suggested multiple progression pathways and identified +8q as an early event. The mixture model suggested two independent pathways namely a major pathway with ?8p and a less frequent pathway with +9q. The distance‐based tree identified three progression pathways, one characterized by ?8p, another by ?3p and the third by alterations +11q and +7p. Differences were observed in cytogenetic pathways of node‐positive and node‐negative oral cancers. Node‐positive cancers were characterized by more non‐random aberrations (n = 11) and progressed via ?8p or ?3p. On the other hand, node‐negative cancers involved fewer non‐random alterations (n = 6) and progressed along ?3p. In summary, the tree models for oral cancers provided novel information about the interactions between genetic alterations and predicted their probable order of occurrence. © 2009 UICC 相似文献
110.
Su FC Shi C Crownover R Swanson G Papanikolaou N 《Technology in cancer research & treatment》2008,7(4):287-293
During helical tomotherapy, gantry angle accuracy is one of the vital geometric factors that assure accurate dose delivery to the target and organs at risk adjacent to it. The purpose of this study is to investigate the dosimetric impact of gantry angle misalignment on the target volume and critical organs during helical tomotherapy treatment. Five prostate cases were chosen to calculate the effects of gantry angle deviations on both patient-specific delivery quality assurance (DQA) and helical tomotherapy treatment plans. For DQA plans, the cheese phantom was rotated for up to +/-5 degrees from the preset position to simulate the gantry angle deviations during tomotherapy. Point doses at 5 mm below the isocenter and the dose distribution for each gantry angle were measured and reconstructed, respectively. For helical tomotherapy treatment plans, the same gantry misalignment effect was simulated by adjusting the automatic roll correction for up to +/-5 degrees using Planned Adaptive software. Variations of dose volume histograms (DVHs) and isodose lines were evaluated for both target and critical organs. There was no significant difference found, however, among the point dose measurements for gantry rotation up to +/-5 degrees in DQA plans. Shifts of isodose lines could be observed for gantry rotations larger than +/-27 degrees. Dosimetric discrepancies (less than 2%) were also found among DVHs of the PTV in the cases when gantry angle misalignment was larger than +/-2 degrees. However, for DVHs of either bladder or rectum under different gantry rotations, no significant differences were detected when gantry angle errors were up to +/-5 degrees. In summary, point dose measurements alone cannot reveal the dosimetric deviation due to gantry angle misalignment in DQA plans. For a 5 degrees gantry deviation, the dose to PTV increased by 0.5% comparing to the planned dose. The influence on organs at risk, i.e., rectum and bladder, is also negligible. Further studies are needed on the dosimetric impacts of gantry angle deviations for other treatment sites. 相似文献