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European Spine Journal - Hip and spine pathology can alter the biomechanics of spino-pelvic mobility. Lumbar spine fusions can reduce the mobility of the lumbar spine and therefore result in...  相似文献   
73.
In both humans and animals, immunoglobulin (Ig)G autoantibodies are less frequent but more pathogenic than IgM autoantibodies, suggesting that controls over Ig isotype switching are required to reinforce B cell self-tolerance. We have used gene targeting to produce mice in which hen egg lysozyme (HEL)-specific B cells can switch to all Ig isotypes (SWHEL mice). When crossed with soluble HEL transgenic (Tg) mice, self-reactive SWHEL B cells became anergic. However, in contrast to anergic B cells from the original nonswitching anti-HEL x soluble HEL double Tg model, self-reactive SWHEL B cells also displayed an immature phenotype, reduced lifespan, and exclusion from the splenic follicle. These differences were not related to their ability to Ig class switch, but instead to competition with non-HEL-binding B cells generated by VH gene replacement in SWHEL mice. When activated in vitro with B cell receptor (BCR)-independent stimuli such as anti-CD40 monoclonal antibody plus interleukin 4 or lipopolysaccharide (LPS), anergic SWHEL double Tg B cells proliferated and produced IgG anti-HEL antibodies as efficiently as naive HEL-binding B cells from SWHEL Ig Tg mice. These results demonstrate that no intrinsic constraints to isotype switching exist in anergic self-reactive B cells. Instead, production of IgG autoantibodies is prevented by separate controls that reduce the likelihood of anergic B cells encountering BCR-independent stimuli. That bacteria-derived LPS could circumvent these controls may explain the well-known association between autoantibody-mediated diseases and episodes of systemic infection.  相似文献   
74.
Background contextThe rs11190870 single nucleotide polymorphism in the 3'-flanking region of the LBX1 gene has been implicated in the etiology of adolescent idiopathic scoliosis (AIS). A thorough appraisal of the evidence supporting this association has not been previously attempted.PurposeTo provide a comprehensive assessment and synthesis of the currently available evidence on the association between rs11190870 and AIS.Study designA systematic review and meta-analysis.MethodsThis review followed the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. PubMed (MEDLINE), EMBASE, Scopus, and HuGE Literature Finder databases were systematically searched through November 2013 to identify relevant studies following a sensitive strategy. Summary odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were estimated using the fixed-effect inverse variance model for allelic (T vs. C) and genotypic comparisons.ResultsMeta-analysis of four studies conducted in East Asian populations (n=3,215 AIS cases and n=15,347 controls) found a highly statistically significant and robust association between rs11190870 and AIS. Comparison of summary ORs indicated a codominant model effect of the T allele. Carriers of the TC and TT genotypes were 69% (OR=1.69, 95% CI: 1.48–1.94, p<.001) and 162% (OR=2.62, 95% CI: 2.28–3.02, p<.001), respectively, more likely to have AIS compared with carriers of the CC genotype.ConclusionsBased on a comprehensive analysis of the currently available evidence, rs11190870 is likely a susceptibility variant for AIS in East Asians. Further investigation of this association is necessary in other populations.  相似文献   
75.
This study reported the distribution of polycyclic aromatic hydrocarbons (PAHs) concentrations simultaneously obtained in gas/rain/particle in rain event from 2010 to 2012 in Osaka, Japan. A sampling method for rain and the materials of a rain collector were also surveyed. Benzene and a glass bottle were used to prevent the decrease of PAHs in rainwater. The average concentration of Σ9PAHs in rainwater ranged between 17.49 and 646.52 ng dm?3. The mean ratio of these Σ9PAHs in gas versus particles was 77.9 and 68.3 % during rain and no rain, respectively. During rain, the PAHs in particles were scavenged by rain and were incorporated via washout by collision with each other. Therefore, the ratio of PAHs in rainwater was similar to that in particles. The low molecular weight LMW-PAHs from gas were recognized as being dissolved in rain but did not affect the ratio of PAHs in rain. Four rings PAH were dominant in gas/rain/particles. The seasonal variation of Σ9PAHs in rainwater was reported and discussed, and the PAHs levels during the winter and spring were higher compared with that of summer and autumn. Furthermore, the sampling method of PAHs in snow is also developed.  相似文献   
76.
Journal of Interventional Cardiac Electrophysiology - Conduction disturbances after transcatheter aortic valve replacement (TAVR) requiring pacemaker (PPM) implantation are a known complication and...  相似文献   
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78.
AIM: We used Near Infrared Spectrophotometry (NIRS) during arterial occlusion to measure resting skeletal muscle oxygen consumption in chronic heart failure (CHF) patients and in age-matched healthy volunteers (HVs). METHODS: Fifteen CHF patients (ten males) and eleven HVs (six males) had echocardiographic evaluation followed by measurement of the oxygen consumption of the brachioradialis muscle using NIRS. This involved continuous measurement of the oxygenated haemoglobin concentration ([Oxy-Hb]) and deoxy-haemoglobin concentration ([Deoxy-Hb]) with an Oxiplex TS NIRS probe first under basal overnight fasted resting conditions followed by 1 min of forearm arterial occlusion. A linear decline was observed in [Oxy-Hb-Deoxy-Hb] during the arterial occlusion and the oxygen consumption rate was calculated from the initial slope observed. RESULTS: CHF patients were 59+/-2.8 years old with Left Ventricular Ejection Fraction (LVEF) 31%+/-2.2 and the HVs were 52+/-4.8 years old with LVEF 62%+/-2.5. The resting muscle oxygen consumption rate was significantly reduced in CHF patients versus HVs (0.04+/-0.01 mlO(2)/min/100 g versus 0.07+/-0.01 mlO(2)/min/100 g) p<0.005. CONCLUSIONS: There is a significant reduction in resting oxygen consumption per gram of tissue in skeletal muscle of patients with CHF.  相似文献   
79.
A novel protein translocation system, the type-6 secretion system (T6SS), may play a role in virulence of Campylobacter jejuni. We investigated 181 C. jejuni isolates from humans, chickens, and environmental sources in Vietnam, Thailand, Pakistan, and the United Kingdom for T6SS. The marker was most prevalent in human and chicken isolates from Vietnam.  相似文献   
80.
目的 :了解我国卫生应急人员对突发公共卫生事件风险评估的认知状况,从文化程度、职称情况、单位性质、单位级别等方面进行比较,为提高卫生应急人员风险评估的认识和能力提供依据。方法 :采用问卷调查的方法,对全国(大陆地区)31个省(自治区、直辖市)承担突发公共卫生事件应急处置的卫生应急工作人员进行调查。采用描述性分析和χ2检验对调查数据进行分析。结果 :我国卫生应急人员对风险评估概念熟悉程度较低,且不同学历、不同职称、不同工作年限、不同机构、不同层级之间的认知存在一定差异;对风险评估工作内容的认知也存在分歧。结论 :应加强风险评估培训,健全风险评估制度,以全面提高卫生应急人员对风险评估的认知水平。  相似文献   
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