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901.
902.
Jolinda LD Schram Joost Oude Groeniger Merel Schuring Karin I Proper Sandra H van Oostrom Suzan JW Robroek Alex Burdorf 《Scandinavian journal of work, environment & health》2021,47(2):127
Objective:Using a novel mediation method that presents unbiased results even in the presence of exposure–mediator interactions, this study estimated the extent to which working conditions and health behaviors contribute to educational inequalities in self-rated health in the workforce.Methods:Respondents of the longitudinal Survey of Health, Ageing, and Retirement in Europe (SHARE) in 16 countries were selected, aged 50–64 years, in paid employment at baseline and with information on education and self-rated health (N=15 028). Education, health behaviors [including body mass index (BMI)] and working conditions were measured at baseline and self-rated health at baseline and two-year follow-up. Causal mediation analysis with inverse odds weighting was used to estimate the total effect of education on self-rated health, decomposed into a natural direct effect (NDE) and natural indirect effect (NIE).Results:Lower educated workers were more likely to perceive their health as poor than higher educated workers [relative risk (RR) 1.48, 95% confidence interval (CI) 1.37–1.60]. They were also more likely to have unfavorable working conditions and unhealthy behaviors, except for alcohol consumption. When all working conditions were included, the remaining NDE was RR 1.30 (95% CI 1.15–1.44). When BMI and health behaviors were included, the remaining NDE was RR 1.40 (95% CI 1.27–1.54). Working conditions explained 38% and health behaviors and BMI explained 16% of educational inequalities in health. Including all mediators explained 64% of educational inequalities in self-rated health.Conclusions:Working conditions and health behaviors explain over half of the educational inequalities in self-rated health. To reduce health inequalities, improving working conditions seems to be more important than introducing health promotion programs in the workforce. 相似文献
903.
Nelson L. Rhodus Bin Cheng Sandra Myers Walter Bowles Vu Ho Frank Ondrey 《Clinical immunology (Orlando, Fla.)》2005,114(3):278
To explore the feasibility of detection of the level of NF-κB-dependent cytokines in oral fluids from patient with oral lichen planus (OLP) for clinical application, 13 OLP subjects were enrolled in the study as were 13 age–sex-matched controls. In each subject, the whole unstimulated saliva (WUS), mixture of saliva and isotonic saline oral rinse (Saliva-NaCl), and lesion tissue transudates (TT) were collected by standard techniques. The level of cytokines, TNF-alpha, IL-1-alpha, IL-6, and IL-8 in three types of oral fluids was determined by ELISA. In the three types of oral fluids, a significantly higher level of these cytokines was detected in OLP patients than in normal controls. These results indicate that NF-κB-dependent inflammatory cytokines may be detected at increased levels in certain oral fluids which may have diagnostic and prognostic potential for monitoring disease activity and making therapeutic decisions in patients with OLP. 相似文献
904.
In many organisms completion of the first meiotic cell division depends on the correct assembly and disassembly of the synaptonemal
complex (SC). This is a structure discovered a little over 50 years ago, which is formed by the close association of axes
of homologous sister chromatid pairs. Its structure varies between organisms, although it retains a common tripartite organization
in species as evolutionarily distant as budding yeast and humans. In mammals it is essential for crossover formation and completion
of meiosis. Components of the mammalian SC have been identified only in the last 15 years, and mouse genetic approaches have
started revealing the importance for this structure only in the past 5 years. Here we discuss the progress that has been made
in the field of the mammalian SC and what approaches could be considered for its further study. 相似文献
905.
Luca Antiga Marina Piccinelli Lorenzo Botti Bogdan Ene-Iordache Andrea Remuzzi David A. Steinman 《Medical & biological engineering & computing》2008,46(11):1097-1112
We present a modeling framework designed for patient-specific computational hemodynamics to be performed in the context of
large-scale studies. The framework takes advantage of the integration of image processing, geometric analysis and mesh generation
techniques, with an accent on full automation and high-level interaction. Image segmentation is performed using implicit deformable
models taking advantage of a novel approach for selective initialization of vascular branches, as well as of a strategy for
the segmentation of small vessels. A robust definition of centerlines provides objective geometric criteria for the automation
of surface editing and mesh generation. The framework is available as part of an open-source effort, the Vascular Modeling
Toolkit, a first step towards the sharing of tools and data which will be necessary for computational hemodynamics to play
a role in evidence-based medicine. 相似文献
906.
Embryo transfer (ET) is the last stage of extracorporal fertilization during which the embryo is placed in the uterine cavity with a medium-filled catheter 2–3 days after in vitro fertilization. While fertilization in the laboratory occurs at very high rates (>:90%), the overall success of the procedure (i.e., take home baby) is still very low (<25%) and assumed to be mainly due to implantation failure. A computational model was developed to simulate ET within the uterine cavity by a fluid-filled catheter inserted into a two-dimensional channel with oscillating walls. The results showed that the speed at which the embryos are injected from the catheter dominates the procedure and controls the velocity of their transport within the uterine cavity. ET at excessively high injection speeds may lead to ectopic pregnancies, while uterine peristalsis affects transverse dispersion only during injection at low injection speeds. The presence of the catheter within the uterus does not affect flow patterns downstream of its tip. The potential risks to implantation failure due to mechanical factors involved in the ET processes are discussed. © 2003 Biomedical Engineering Society.
PAC2003: 8719-j, 8710+e 相似文献
907.
Materials are distributed throughout the body of mammals by fractal networks of branching tubes. Based on the scaling laws of the fractal structure, the vascular tree is reduced to an equivalent one-dimensional, tube model. A dispersion–convection partial differential equation with constant coefficients describes the heterogeneous concentration profile of an intravascular tracer in the vascular tree. A simple model for the mammalian circulatory system is built in entirely physiological terms consisting of a ring shaped, one-dimensional tube which corresponds to the arterial, venular, and pulmonary trees, successively. The model incorporates the blood flow heterogeneity of the mammalian circulatory system. Model predictions are fitted to published concentration-time data of indocyanine green injected in humans and dogs. Close agreement was found with parameter values within the expected physiological range. © 2003 Biomedical Engineering Society.
PAC2003: 8710+e, 8719Hh, 8719Uv 相似文献
908.
Robson C. Gutierre Mizue I. Egami Marta M. Antoniazzi Carlos Jared 《Comparative clinical pathology》2008,17(4):221-228
The caecilians (Amphibia, Gymnophiona) constitute one of the least known groups of terrestrial vertebrates because most species
live underground in quite inaccessible environments. Siphonops annulatus is an exclusively fossorial species and is the most extensively distributed caecilian in South America. Little is known of
this order concerning circulating granulocytes, including their morphological and cytochemical structure and ultrastructure.
This paper is part of a project covering the study of granulocytes in representative species of the order Amphibia. Blood
extensions were carried out and submitted to Leishman, Toluidine Blue, Periodic acid Schiff, Sirius Red and hydrogen o-toluidine peroxide methods. Part of the samples was prepared for conventional transmission electron microscopy. Among granular
leukocytes, mature and immature neutrophils and eosinophils were identified, plus basophils. The most frequent granulocyte
encountered in S. annulatus peripheral blood is the neutrophil. This is a cell with a hyper-segmented nucleus and with a very clear cytoplasm when compared
to the eosinophil, which presents large cytoplasmic acidophilic granules. On the other hand, the basophils present basophilic
and metachromatic granules. Glycogen was detected in the cytoplasm of the neutrophils and eosinophils, while basic protein
rich in amino acids was observed in the eosinophil’s granules. Myeloperoxidase activity was detected in the cytoplasm of the
neutrophils and eosinophils. Neutrophils were ultrastructurally detected with three types of small granules: eosinophils with
large and small spherical granules and basophils with large spherical granules with lamellate structures. 相似文献
909.
David P. Bazett-Jones Ren Li Eden Fussner Rosa Nisman Hesam Dehghani 《Chromosome research》2008,16(3):397-412
Electron microscopy has been the ‘gold standard’ of spatial resolution for studying the structure of the cell nucleus. Electron
spectroscopic imaging (ESI) offers advantages over conventional transmission electron microscopy by eliminating the need for
heavy-atom contrast agents. ESI also provides mass-dependent and element-specific information at high resolution, permitting
the distinguishing of structures that are primarily composed of protein, DNA, or RNA. The technique can be applied to understand
the structural consequences of epigenetic modifications, such as modified histones, on chromatin fiber morphology. ESI can
also be applied to elucidate the multifunctional behavior of subnuclear ‘organelles’ such as the nucleolus and promyelocytic
leukemia nuclear bodies.
The authors dedicate this paper to the memory of Ying Ren (1961–2007). We all benefited from knowing her. Our research advanced
through the technical creativity she provided. 相似文献
910.