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61.
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Muthucumaru M Keys C Kimber C Ferguson P Varma P Cheng W 《Journal of paediatrics and child health》2012,48(3):259-262
Aim: Bicycle riding is a common recreational and sport activity enjoyed by many children. Bicycle accidents are a common cause of abdominal injuries. We aim to establish the trend and the associated risk factor(s) of bicycle‐related abdominal injuries. Methods: A retrospective review of all children admitted following bicycle accidents to a single tertiary referral centre was carried out over an approximately 5‐year period. The data were tabulated and regression analyses were carried out. Results: Over the study period, 196 children were admitted into the Emergency Department. Abdominal injuries (16%) were the third largest group after orthopaedic and head injuries. There were 19 major visceral injuries, seven of whom underwent major surgeries. Forty‐two percent (8/19) of these major injuries were related to stunts. Over the same period, no child with head injury required any surgical intervention. In addition, there was a definite trend that abdominal injuries were accounting for greater percentage of bicycle‐related injuries in children. Conclusions: Severe intra‐abdominal trauma following bicycle injuries appears to be seen more often in adolescent males, especially when related to BMX stunts. These injuries have surpassed head injuries as the prime cause of morbidity from bicycle accidents. These injuries are largely preventable. 相似文献
63.
Pegg E Pandit H Gill HS Keys GW Svard UG O'Connor JJ Murray DW 《The Journal of bone and joint surgery. British volume》2011,93(12):1610-1616
Since the Oxford knee was first used unicompartmentally in 1982, a small number of bearings have fractured. Of 14 retrieved bearings, we examined ten samples with known durations in situ (four Phase 1, four Phase 2 and two Phase 3). Evidence of impingement and associated abnormally high wear (> 0.05 mm per year) as well as oxidation was observed in all bearings. In four samples the fracture was associated with the posterior radio-opaque wire. Fracture surfaces indicated fatigue failure, and scanning electron microscopy suggested that the crack initiated in the thinnest region. The estimated incidence of fracture was 3.20% for Phase 1, 0.74% for Phase 2, 0.35% for Phase 3, and 0% for Phase 3 without the posterior marker wire. The important aetiological factors for bearing fracture are impingement leading to high wear, oxidation, and the posterior marker wire. With improved surgical technique, impingement and high wear should be prevented and modern polyethylene may reduce the oxidation risk. A posterior marker wire is no longer used in the polyethylene meniscus. Therefore, the rate of fracture, which is now very low, should be reduced to a negligible level. 相似文献
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Allele distributions for nine tetrameric short tandem repeat (STR) loci D3S1358, D5S818, D7S820, D8S1179, D13S317, D18S51, D21S11, FGA and vWA were determined in Chamorros and Filipinos residing in Guam. There was little evidence for departures from Hardy-Weinberg expectations (HWE) in any of the populations. Based on the exact test, the only locus that departs significantly from HWE is D8S1179 (p=0.005, Chamorros; p=0.030, Filipinos). There is little evidence for association of alleles between the loci in these databases. The number of pairwise locus departures from expectations is no more than would be expected by chance. The allelic frequency data are similar to comparable published data within the same population group (e.g., a comparison of Filipinos with Filipinos) and significantly different compared with other major population groups, such as African Americans, Caucasians, and Hispanics. The F(ST) estimate over all nine STR loci is 0.0090. 相似文献
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Phenotypic and genotypic analyses of Neisseria gonorrhoeae isolates that express frequently recovered PorB PIA variable region types suggest that certain P1a porin sequences confer a selective advantage for urogenital tract infection 下载免费PDF全文
Garvin LE Bash MC Keys C Warner DM Ram S Shafer WM Jerse AE 《Infection and immunity》2008,76(8):3700-3709
Typing of the porB variable region (VR) is an epidemiological tool that classifies gonococcal strains based on sequence differences in regions of the porB gene that encode surface-exposed loops. The frequent isolation of certain porB VR types suggests that some porin sequences confer a selective advantage during infection and/or transmission. Alternatively, certain porin types may be markers of strains that are successful due to factors unrelated to porin. In support of the first hypothesis, here we show urogenital tract isolates representing the most common PIA VR types identified in an urban clinic in Baltimore, MD, over a 10-year period belonged to several different clonal types, as determined by pulsed-field gel electrophoresis (PFGE). Serum resistance, which was confirmed by factor H and C4b-binding protein binding studies, was more often associated with gonococcal the most common VR types. In contrast, three porin-independent phenotypes, namely, lactoferrin utilization, beta-lactamase production, and multiple transferable resistance (Mtr), were segregated with the PFGE cluster and not with the VR type. Data combined with another PIA strain collection showed a strong correlation between serum resistance and the most common VR types. A comparison of VR typing hybridization patterns and nucleotide sequences of 12 porB1a genes suggests that certain porin loop 1, 3, 6, and/or 7 sequences may play a role in the serum resistance phenotype. We conclude that some PorB PIA sequences confer a survival or transmission advantage in the urogenital tract, perhaps via increased resistance to complement-mediated killing. The capacity of some porin types to evade a porin-specific adaptive immune response must also be considered. 相似文献
69.
Lasantha Gunasekara Mustafa Al-Saiedy Francis Green Ryan Pratt Candice Bjornson Ailian Yang W. Michael Schoel Ian Mitchell Mary Brindle Mark Montgomery Elizabeth Keys John Dennis Grishma Shrestha Matthias Amrein 《Journal of cystic fibrosis》2017,16(5):565-572
Background
Airway surfactant is impaired in cystic fibrosis (CF) and associated with declines in pulmonary function. We hypothesized that surfactant dysfunction in CF is due to an excess of cholesterol with an interaction with oxidation.Methods
Surfactant was extracted from bronchial lavage fluid from children with CF and surface tension, and lipid content, inflammatory cells and microbial flora were determined. Dysfunctional surfactant samples were re-tested with a lipid-sequestering agent, methyl-β-cyclodextrin (MβCD).Results
CF surfactant samples were unable to sustain a normal low surface tension. MβCD restored surfactant function in a majority of samples.Mechanistic studies showed that the dysfunction was due to a combination of elevated cholesterol and an interaction with oxidized phospholipids and their pro-inflammatory hydrolysis products.Conclusion
We confirm that CF patients have impaired airway surfactant function which could be restored with MβCD. These findings have implications for improving lung function and mitigating inflammation in patients with CF. 相似文献70.