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951.
952.
Objectives
To examine epidemiological trends of Traumatic Brain Injury (TBI) treated in the Emergency Department (ED), identify demographic groups at risk of TBI, and determine the factors associated with hospitalization following an ED visit for TBI.Methods
A province-wide database was used to identify all ED visits for TBI in Ontario, Canada between April 2002 and March 2010. Trends were analyzed using linear regression, and predictors of hospital admission were evaluated using logistic regression.Results
There were 986,194 ED visits for TBI over the eight-year study period, resulting in 49,290 hospitalizations and 1,072 deaths. The age- and sex-adjusted rate of TBI decreased by 3%, from 1,013.9 per 100,000 (95% CI 1,008.3–1,010.6) to 979.1 per 100,000 (95% CI 973.7–984.4; p = 0.11). We found trends towards increasing age, comorbidity level, length of stay, and ambulatory transport use. Children and young adults (ages 5–24) sustained peak rates of motor vehicle crash (MVC) and bicyclist-related TBI, but also experienced the greatest decline in these rates (p = 0.003 and p = 0.005). In contrast, peak rates of fall-related TBI occurred among the youngest (ages 0–4) and oldest (ages 85+) segments of the population, but rates remained stable over time (p = 0.52 and 0.54). The 5–24 age group also sustained the highest rates of sports-related TBI but rates remained stable (p = 0.80). On multivariate analysis, the odds of hospital admission decreased by 1% for each year over the study period (OR = 0.991, 95% CI = 0.987–0.995). Increasing age and comorbidity, male sex, and ambulatory transport were significant predictors of hospital admission.Conclusions
ED visits for TBI are involving older populations with increasingly complex comorbidities. While TBI rates are either stable or declining among vulnerable groups such as young drivers, youth athletes, and the elderly, these populations remain key targets for focused injury prevention and surveillance. Clinicians in the ED setting should be cognizant of factors associated with hospitalization following TBI.Level of Evidence
III.Study Design
Cross-sectional. 相似文献953.
954.
Sarah R. Fennell Wayne Powell Frank Wright Gavin Ramsay Robbie Waugh 《Plant Systematics and Evolution》1998,212(3-4):247-259
The chloroplasttrnL intron from 46 differentVicia accessions, representing five of the nine sections of the genusVicia subg.Vicia sensuMaxted (1991a) were amplified by the Polymerase Chain Reaction (PCR) using oligonucleotide primers homologous to conserved regions intrnL. The products fell into two distinct groups; those of approximately 250 nt and those of around 450 nt in length. Of these, products from 17 differentVicia species were cloned and their nucleotide sequences determined. Multiple alignments were assembled and phylogenetic trees constructed by the weighted least-squares distance method. ALathyrus latifolius trnL intron sequence was used as an outgroup. The resulting trees clearly group and separate the sectt.Narbonensis, Bithynica andFaba species but were less able to distinguish species from sectt.Hypechusa andPeregrinae. Based on these sequence data,V. faba appears to be more distant from sect.Narbonensis than sectt.Hypechusa andPeregrinae. The results are in general agreement with a recent treatment ofVicia subg.Vicia (Maxted 1993) and lend further support to placingV. faba in the monospecific sect.Faba. 相似文献
955.
Chadwick W Zhou Y Park SS Wang L Mitchell N Stone MD Becker KG Martin B Maudsley S 《PloS one》2010,5(12):e14352
Oxidative exposure of cells occurs naturally and may be associated with cellular damage and dysfunction. Protracted low level oxidative exposure can induce accumulated cell disruption, affecting multiple cellular functions. Accumulated oxidative exposure has also been proposed as one of the potential hallmarks of the physiological/pathophysiological aging process. We investigated the multifactorial effects of long-term minimal peroxide exposure upon SH-SY5Y neural cells to understand how they respond to the continued presence of oxidative stressors. We show that minimal protracted oxidative stresses induce complex molecular and physiological alterations in cell functionality. Upon chronic exposure to minimal doses of hydrogen peroxide, SH-SY5Y cells displayed a multifactorial response to the stressor. To fully appreciate the peroxide-mediated cellular effects, we assessed these adaptive effects at the genomic, proteomic and cellular signal processing level. Combined analyses of these multiple levels of investigation revealed a complex cellular adaptive response to the protracted peroxide exposure. This adaptive response involved changes in cytoskeletal structure, energy metabolic shifts towards glycolysis and selective alterations in transmembrane receptor activity. Our analyses of the global responses to chronic stressor exposure, at multiple biological levels, revealed a viable neural phenotype in-part reminiscent of aged or damaged neural tissue. Our paradigm indicates how cellular physiology can subtly change in different contexts and potentially aid the appreciation of stress response adaptations. 相似文献
956.
957.
Use of Gas Chromatography for Determining Catabolic Products of Arginine by Bacteria 总被引:4,自引:0,他引:4 下载免费PDF全文
A rapid and sensitive procedure for determining catabolic products of arginine metabolism by bacteria was developed. The method consists of inoculating a solution of L-arginine with a heavy cell suspension of the test organism. After a 2-hr incubation period, dissimilation products (citrulline, ornithine, agmatine, putrescine) are converted to volatile derivatives and analyzed by gas-liquid chromatography. Compared with conventional microbiological tests, the new procedure is rapid and can be used for sensitive quantitative measurements of specific metabolites from arginine. 相似文献
958.
Synthesis of hydroxamic acids using SynPhase™ crowns: Development of the hydroxylamine trityl linker
Ede Nicholas J. James Ian W. Krywult Beata M. Griffiths Rachael M. Eagle Susan N. Gubbins Ben Leitch Jeffrey A. Sampson Wayne R. Bray Andrew M. 《International journal of peptide research and therapeutics》1999,6(2-3):157-163
Summary The synthesis of peptide and small molecule hydroxamic acids utilising SynPhase™ crowns is demonstrated. A hydroxylamine trityl linker is generated from chlorotrityl derivatised Synphase™ crowns by reaction with N-hydroxyphthalimide followed by subsequent deprotection. The loading of hydroxylamine crowns is
quantified spectrophotometrically by measuring phthalhydrazide absorbance at 346 nm. 相似文献
959.
Streptococcin A-FF22 (SA-FF22) is a type AII linear lantibiotic produced by Streptococcus pyogenes strain FF22. Sequence analysis of an approximate 10 kb region of DNA showed it to contain nine open reading frames arranged in three operons responsible for regulation, biosynthesis and immunity of SA-FF22. This region is organized similarly to the Lactococcus lactis lacticin 481 region, however, unlike lacticin 481, a two-component regulatory system is essential for SA-FF22 production. Located immediately downstream of the scn region is a putative transposase gene, the presence of which supports earlier data that indicated a mobile nature to this region. 相似文献
960.
Four hundred and eight quantitative grab samples collected during the winter and spring of 1977 from the New England Continental Shelf (Georges Bank) yielded 333 species of polychaetes. Polychaetes comprised 53.8% of the number of all infaunal species, 53% of the density, and 60.5% of the wet weight biomass for all soft-bodied organisms, at least for the winter. Mean number of species and mean density was significantly higher in the spring than in the winter. Mean values of number of species, H', SDN, density, and biomass were associated with various environmental factors. Based on numerical classification (normal and inverse) five polychaete site groups were identified. To a great extent these site groups were molded by major physical, geologic and biologic processes which influence the productivity of this ecologically and economically important area. 相似文献