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51.
The distinction between true and suspected poisoning in children has not been made clear in previous work on childhood poisoning. A study of suspected poisoning in children under 15 years of age in a defined population of North East Bristol from November 1970 to July 1973 carried out by the Health Education Council Medical Research Division included 53,000 child-years at risk. The number of suspected poisonings was 3-4/1000 population aged under 15 years per year, with a higher incidence in younger age groups. Detailed investigation of the circumstances of the accidents carried out by a multidisciplinary team showed that at least 65%, and possibly as many as 78% were poisoning scares and not true poisoning. The evidence used by the casualty doctor and by the parents to diagnose poisoning was explored, and in many cases was circumstantial. Children with fathers in nonmanual occupations were over-represented. This may reflect differences in patterns of utilization behaviour rather than true differences in incidence.  相似文献   
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Summary: Xenotransplantation of non-human organs into human recipients has long been proposed as a possible strategy to overcome the acute shortage of donor organs. However, vascular organ transplants to humans from phylogenetically disparate species such as the pig are not currently possible due to a rapid rejection process termed hyperacute rejection. This process is initiated by the binding of host pre-formed 'natural antibodies' to the donor vascular endothelium, activation of the host complement system and activation or injury of the donor endothelial cells, leading to intravascular coagulation and loss of the graft due to ischaemic necrosis within minutes to hours of engraftment. Prevention of natural antibody binding and complement activation is viewed as paramount to preventing hyperacute rejection. Even if hyperacute rejection can be prevented, further barriers to successful discordant xenografts such as delayed xenograft rejection and a donor-directed cell-mediated rejection process will still represent major obstacles. This review examines recent advances being made in the various areas of xenograft research and the potential clinical application of pig-to-human xenografts that these strategies may bring.  相似文献   
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The prevalence of osteopenia in children with inflammatory bowel disease (IBD) is unknown. The effect of nutritional state, disease activity, and steroid therapy on bone mineral content (BMC) of whole body, lumbar spine, and left femoral neck measured by dual energy x ray absorptiometry in 32 children with IBD was assessed by comparison with 58 healthy local school children. Using the control data, a predicted BMC was calculated taking into account bone area, age, height, weight, and pubertal stage. The measured BMC in children with IBD was expressed as a percentage of this predicted value (% BMC). Mean (SD) % BMC was significantly reduced for the whole body and left femoral neck in the children with IBD (97.0 (4.5)% and 93.1 (12.0)% respectively, p < 0.05). Of the children with IBD, 41% had a % BMC less than 1 SD below the mean for the whole body and 47% at the femoral neck. Reduction in % BMC was associated with steroid usage but not with the magnitude of steroid dose, disease activity, or biochemical markers of bone metabolism. In conclusion, osteopenia is relatively common in childhood IBD and may be partly related to the previous use of steroids.  相似文献   
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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   
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体外膜肺氧合技术支持治疗期间患者血乳酸浓度及其预后   总被引:2,自引:1,他引:2  
目的:探讨体外膜肺氧合支持治疗患者血乳酸浓度的变化和预后。方法:于2004-12/2006-09在中国医学科学院阜外心血管病医院因脱离体外循环困难的心脏外科术后患者、扩张性心肌病和冠状动脉粥样硬化性心脏病发生心源性休克的患者共40例进行了体外膜肺氧合支持治疗,按年龄和存活预后分为4组:成人存活组、成人死亡组、儿童存活组、儿童死亡组。分析4组的治疗效果,分别抽取各组患者体外膜肺氧合建立时、体外膜肺氧合运转6h、运转中间时点、停机前6h、停机时的血乳酸浓度。结果:①体外膜肺氧合支持治疗患者40例,成人组26例,20例脱机,16例生存,10例死亡,脱机率76.9%,生存率61.5%;儿童组14例,7例脱机,5例生存,9例死亡,脱机率50.0%,生存率35.0%。②成人或儿童存活组的乳酸浓度都与死亡组有明显差别,存活组血乳酸浓度明显低于死亡组,其中建立和运转6h、中间时点的差异有显著性意义(P<0.05),其余2个时点的差异有非常显著性意义(P<0.001)。组内与建立时比较,中间时点、停止前6h、停止时差异均有显著性意义(P<0.001),血乳酸浓度逐渐降低。结论:经体外膜肺氧合支持治疗的患者,血乳酸浓度明显下降,脱机时血乳酸仍高的患者预后不良。  相似文献   
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