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291.
292.
Claret PL Castillo Jde D Moleón JJ Cavanillas AB Martín MG Vargas RG 《Accident; analysis and prevention》2003,35(2):261-272
This retrospective, paired case-control study was designed to estimate crude and adjusted effects of age and sex on the risk of causing collisions between vehicles with four or more wheels in Spain during the period from 1990 to 1999. We selected all 220284 collisions registered from 1990 to 1999 in the Spanish Dirección General de Tráfico (DGT) traffic crash database in which only one driver committed any infraction. Information was collected about age, sex and several confounding factors for both the responsible and paired-by-collision nonresponsible drivers. Crude and adjusted odds ratios (aORs) were calculated for each age and sex category. For men, the lowest risk was seen for drivers aged 25-49 years. Below the age of 35 years the crude odds ratio (cOR) was highest in the 18-24-year-old group (1.61; CI: 1.57-1.65). The risk increased significantly and exponentially after the age of 50 years, to a maximum odds ratio of 3.71 (3.43-4.00) for drivers aged >74 years. In women, the lowest risk values were found for the 25-44-year-old age group. In older women the risk increased significantly with age to a maximum odds ratio of 3.02 (2.31-3.97) in the oldest age group. aOR estimates tended to be lower than crude estimates for drivers younger than 40 years of age, but the opposite was seen for drivers 40 years old and older. Regarding sex differences, among younger drivers crude and aORs for men were higher than for women. Our results suggest that the risk of causing a collision between vehicles with four or more wheels is directly dependent on the driver's age. 相似文献
293.
The authors synthesize the main etiopathogenetic, physiopathologic and clinic findings of CSP and describe the pharmacs employed in the treatment of disease: corticosteroids, cyclosporin, penicillamine, colchicine, tacrolimus, metotrexate, hydrophylic bile salts. They outline the poor or none therapeutic activity of the majority of these and stress the improvement of some clinical parameters after prolonged use of hydrophilic bile salts. However none of the used pharmacs can stop the pathologic course of the disease. At the end authors remember the usefulness of liposoluble vitamins to prevent carential syndromes. 相似文献
294.
Lansford Jennifer E.; Sherman Aurora M.; Antonucci Toni C. 《Canadian Metallurgical Quarterly》1998,13(4):544
This study examines L. L. Carstensen's (see records 1993-98639-005 and 1996-22608-001) socioemotional selectivity theory within and across three cohorts spanning 4 decades. Socioemotional selectivity theory predicts that as individuals age, they narrow their social networks to devote more emotional resources to fewer relationships with close friends and family. Data from 3 cohorts of nationally representative samples were analyzed to determine whether respondents' satisfaction with the size of their social networks differed by age, cohort, or both. Results support socioemotional selectivity theory: More older adults than younger adults were satisfied with the current size of their social networks rather than wanting larger networks. These findings are consistent across all cohorts. Results are discussed with respect to social relationships across the life course. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
295.
Ossi Horovitz Gheorghe Tomoaia Aurora Mocanu Traianos Yupsanis Maria Tomoaia-Cotisel 《Gold bulletin》2007,40(3):213-218
Gold nanoparticles (size from 10 to 50 nm) were synthesized by three different methods and were characterized by UV-Vis spectroscopy
and transmission electron microscopy (TEM). The shape and size distribution of gold nanoparticles were determined. The interaction
of major storage protein extracted and purified from aleurone cells of barley with the gold colloids has been examined using
absorption UV-Vis spectroscopy and TEM observations. These investigations evidence the binding of aleurone protein to gold
nanoparticles. This binding might occur by electrostatic forces between the negatively charged citrate capped gold particles
and the positively charged groups of the protein (e.g., arginine and lysine residues). 相似文献
296.
Macario Vicente‐Flores Norma Güemes‐Vera Jos Jorge Chanona‐Prez María de Jesús Perea‐Flores Israel Arzate‐Vzquez Aurora Quintero‐Lira Cinthia Erika Snchez‐Fuentes 《Microscopy research and technique》2021,84(1):12-27
The cuajilote (Parmentiera edulis D.C.) tree produces fibrous fruits with a high content of lignocellulosic compounds. However, this fruit and their fibers have been scarcely studied. For this reason, an integral study of their cellular architecture, physicochemical, micromechanical, and structural properties in two maturity stages were carried out. Physicochemical tests, light, confocal and electron microscopy, microindentation, and X‐ray diffraction were used for the characterization of fruit and their fibers. Chemical analysis showed that the unripe fruits have the highest cellulose content (42.17%), but in ripe fruit the cellulose content decreases (32.76%) while lignin content increases from 35.26 to 40.79%, caused by the lignification of the sclerenchyma fibers. Microstructural and micromechanical studies in the different regions of the fruit provided relevant information about its cellular architecture, distribution of lignocellulosic compounds and its role in the micromechanical properties of their fibers. The thickening cell wall of sclerenchyma fibers was caused by the cellular lignification of the ripe fruits. According to the physicochemical and structural studies, cuajilote fibers are comparable to other fibers obtained from crops rich in lignocellulosic compounds. The current study provided new knowledge about the cellular architecture of fruit and criteria for selecting the ripening stage adequate for the extraction of cellulose or lignin. Furthermore, information regarding the micromechanical properties of their fibers and which structural arrangement could be more convenient for mechanical reinforcement of biodegradable materials was obtained. 相似文献
297.
Roxana-Diana Pasca Aurora Mocanu Simona-Codruta Cobzac Ioan Petean Ossi Horovitz 《Particulate Science and Technology》2014,32(2):131-137
A biogenic approach for the synthesis of gold nanoparticles (GNPs) by reducing chloroauric acid (HAuCl4) with three different plant extracts (from Angelica, Hypericum, and Hamamelis) is described. The content of reducing compounds (polyphenols) in each plant extract was determined by photometric dosing. The formation of GNPs was tracked by ultraviolet-visible spectroscopy and their characterization was performed using transmission electron microscopy (TEM) and atomic force microscopy (AFM) imaging and FTIR spectra. GNPs, with diameters ranging from about 4 nm to 8 nm, were obtained at room temperature and pH value about 8. They present various shapes from spherical, to ovals, heart or polyhedral forms. Generally, the GNPs colloidal dispersions are rather stable in time, and the self assembly of GNPs is sparsely observed. However, at lower concentration of the plant extract the tendency to self aggregation of the GNPs increased. The plant extracts contain reducing agents, compounds with stabilizing effect on the GNPs, but also components which mediate their self assembly. The GNPs obtained by these biogenic syntheses have potential biological and medical applications, taking into account at least two characteristics, their size and aqueous stability. 相似文献
298.
Monari?EmanuelaEmail author Cuoghi?Aurora Bellei?Elisa Bergamini?Stefania Caiazzo?Marialuisa Aucella?Filippo Loschiavo?Carmelo Corazza?Luca Palladino?Giuseppe Sereni?Luisa Atti?Mauro Tomasi?Aldo 《Journal of materials science. Materials in medicine》2014,25(12):5290
In end-stage renal disease patients, extracorporeal dialytic therapy is not able to prevent the accumulation of toxins related to the uremic syndrome, a severe complication that increases morbidity and mortality rate. In this paper, hemoFiltration with on-line Reinfusion (HFR) architecture is used to evaluate the effect of a more permeable membrane on the extraction of medium–high molecular weight molecules. The aim of this study was to compare two polysulphone membranes for convective chamber: polyphenylene High Flux (pHF) and polyphenylene Super High-Flux (pSHF). Fourteen patients were subjected to HFR with pHF and pSHF membranes and ultra filtrate (UF) samples were collected to evaluate molecular weight cut-off (MWCO) and to identify extracted proteins. Furthermore, image analysis software was used in order to evaluate change in protein extraction during the dialysis. The quantification of four proteins by immunoassay demonstrates a higher permeability of pSHF membrane. Two-dimensional electrophoresis (2-DE) gels showed, for both membranes, the greater number of protein spots at 235 min. Some of the identified proteins, involved in nephropathic disease complications, were compared to assess differences in extraction during dialytic treatment by PDQuest analysis. UF proteomic analysis demonstrated a different behavior for the two membranes; pHF membrane was more permeable at the beginning of HFR treatment (15 min), while pSHF membrane at the end of treatment (235 min). Proteomic analysis is a suitable approach to investigate the behavior of different membranes during dialysis. Results indicated that pSHF membrane offers the higher permeability, and showed higher efficiency in removal of middle molecules related to uremic syndrome. 相似文献
299.
Cover Picture: A Unified Sensor Architecture for Isothermal Detection of Double‐Stranded DNA,Oligonucleotides, and Small Molecules (ChemBioChem 5/2015) 下载免费PDF全文
300.
Oscar Martínez‐García Hugo Mújica‐Paz Aurora Valdez‐Fragoso Jorge Welti‐Chanes Enrique Ortega‐Rivas 《Journal of the science of food and agriculture》2007,87(6):1157-1163
Pickling is a preservation method of vegetables by brine immersion. Residual pickling solutions cannot be reused owing to high yeast content and the presence of polygalacturonase, which may produce vegetable softening. It has been reported that high‐pressure homogenization can reduce enzyme activity and microbial population in liquid foods. An investigation was aimed at studying the effect of high‐pressure homogenization cycles on polygalacturonase activity and yeast survival of residual pickling solutions, from processing of six vegetables. Each pickling solution was pumped through a homogenizing valve at 69 MPa pressure and was recirculated up to 15 times. Yeast counts and polygalacturonase activity were determined in treated solutions after being subjected to 1, 2, 5, 10, and 15 pressure cycles. Untreated and thermally treated solutions were used for comparison. Up to 4 log reductions in yeast inactivation was observed after five high‐pressure cycles treatments, contrasted with only 2 log reductions in thermal treatment. No clear relationship between enzyme inactivation and the number of high pressure cycles, or a thermal parallel effect, were observed. Copyright © 2007 Society of Chemical Industry 相似文献