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31.
BackgroundOpen pelvic fractures are rare injuries, associated with high patient morbidity and mortality. Few studies have investigated the impact of patient demographics, comorbidities, and injury related factors on complication and mortality rates. The purpose of this study was to: (1) identify the overall incidence of complications and mortality after open pelvic fractures, (2) compare patient factors between those who did and did not develop complications, (3) identify perioperative independent risk factors for complications and mortality.MethodsA query was performed for patients with open pelvic fractures between 2007 and 2017 using the American College of Surgeons National Trauma Data Bank. Patient and injury specific variables were collected and complications were identified using International Classification of Disease Ninth and Tenth edition Codes. Patient demographic and perioperative data was compared using Fisher’s exact test and chi-square test for categorical variables, and Welch’s t-test for continuous variables. Using pooled data from multiple imputations, logistic regressions were used to calculate odds ratios and confidence intervals of independent risk factors for complications.ResultsA total of 19,834 open pelvic fracture cases were identified, with 9622 patients (48.5%) developing at least one complication. Patients who developed complications were older (35.0 vs 38.1 years), and had higher Injury Severity Scores (17.7 vs 26.5), lower Glasgow Coma Scores (14.2 vs 11.7), and a larger proportion presenting with hypotension (21% vs 6.9%). After pooled regression involving 19 factors, these were the strongest independent predictors of inpatient complication and mortality.ConclusionWe report a mortality rate of 14%, with an inclusive complication rate of 48.5%. Evaluating risk factors for morbidity and mortality for this devastating orthopaedic injury provides knowledge of an inherently sparse population.Level of EvidenceLevel II, Retrospective study.  相似文献   
32.
使用随机系数模型估计医疗组织成员的学习率,衡量组织学习的绩效,并且实证性地采用中国台湾地区全民健康保险数据库,比较台湾医学中心医院对内视镜胆囊切除手术成本控制的学习绩效.通过研究的理论性与实证性,组织管理者可以从微观的角度了解到组织内部的学习能力与不同团体和组织之间的学习率差异.  相似文献   
33.
Absenteeism of health workers in developing countries is common and can severely undermine the reliability of the health system. Therefore, it is important to understand where the prevalence of absenteeism is high. We develop a simple imputation method that combines a Service Delivery Indicators survey and a Service Provision Assessment survey to estimate the prevalence of absenteeism of health workers at the level of regions in Tanzania. The resulting estimates allow one to identify the regions in which the prevalence of absenteeism is significantly higher or lower than the national average and help policymakers determine priority areas for intervention.  相似文献   
34.
目的建立一种基于随机聚合酶链反应的病原细菌基因芯片筛查检测技术。方法用生物学软件分析7种病原菌特异性基因序列的保守性区域,利用Oligo 6.0软件设计针对靶细菌的一系列探针,制备检测用基因芯片。细菌基因组DNA在随机引物扩增中掺入氨基丙烯-dUTP,产物偶联荧光染料后与芯片上探针杂交,通过芯片扫描仪和图像分析软件对结果进行判断。选取19种病原菌基因组DNA进行芯片特异性验证和灵敏度评价,使用问号钩端螺旋体对应靶探针进行基因芯片检测方法重复性验证,并制备问号钩端螺旋体模拟水污染样本进行芯片检测。结果在均一的杂交条件下4种靶细菌均能得到相应特异性杂交图谱,其他非目的细菌均为阴性结果,3种靶细菌基因组DNA最低检测浓度为14.43~363.4 pg/μl,芯片重复性变异系数CV值〈15%,最低可检测含问号钩端螺旋体7×105条/ml模拟水污染样本。结论初步建立的随机聚合酶链反应结合芯片技术的检测方法可用于多种病原菌筛查检测,为细菌高通量筛查与鉴定技术提供了新的思路和实验依据。  相似文献   
35.
ABSTRACT

As part of an ACIAR project aiming at improving community forestry in Solomon Islands, mixed-species plantations were established to assess the feasibility of inter-planting teak (Tectona grandis L. f.) and flueggea (Flueggea flexuosa Muell. Arg). Flueggea is a native hardwood used for timber and fence construction, and early removal of flueggea from a mixed-species stand could have a similar silvicultural outcome to thinning a single-species stand of teak. Using 15N-labelled ammonium sulphate, we investigated the competition for nitrogen (N) between the two species. The 15N-labelled tracer was applied to the soil surface of plots containing pairs of trees, one of each species, in 2-year-old and 4-year-old mixed-species stands, after the pairs of trees were isolated from the rest of the stand by an impermeable membrane. After 12–18 months, the isolated trees were measured and harvested, and each tree component (roots, stem, branch and foliage) was weighed and analysed for total N and 15N enrichment. There was no significant difference in the amounts of 15N between teak and flueggea components at either age, suggesting equal uptake of added 15N-labelled tracer by both species. The 15N amount was greater in stem followed by root, foliage and branch for teak and branch followed by stem, root and foliage for flueggea. About 42% and 55% of the applied 15N tracer were recovered in the 2-year and 4-year plots respectively, suggesting that higher uptake occurs with well-established root structure and that N losses decreased following canopy closure. The amount of total nitrogen was not significantly different between teak and flueggea components at age 2 and 4 years, and may indicate equal access to growth resources, and similar allocation. Although teak had significantly greater stem growth (height, basal area and volume) than flueggea in the 4-year plots, 15N uptake were similar to flueggea, which may mean that competition for growth resources was still minimal or that access to the resources was equal and growth rates differed between species.  相似文献   
36.
背景与目的:宫颈癌的分子靶向治疗具有很好的疗效,同时可以显著减少抗癌药物对人体自身的损伤,因此备受关注。本研究利用噬菌体体内展示技术筛选及鉴定宫颈癌特异性结合肽,将有可能成为化疗药物的靶向载体,为宫颈癌靶向药物治疗奠定基础。方法:体外培养宫颈癌HeLa细胞接种裸鼠,建立肿瘤动物模型。将随机肽库尾静脉注入裸鼠体内,循环15 min,心脏灌注后回收肿瘤组织噬菌体扩增、纯化并以此作为起始物进行第2轮的筛选,如此进行3轮体内筛选后挑取噬菌体克隆,进行免疫组化及ELISA实验,初步鉴定噬菌体克隆对宫颈癌细胞的亲和力及特异性,并将具有强亲和力的克隆进行测序。结果:ELISA结果显示,随机挑选10个噬菌体单克隆中8个克隆对HeLa细胞具有很强的亲和力,将这8个克隆进行测序,获得相同短肽序列LLRSTGF。结论:利用噬菌体展示技术筛选出与宫颈癌细胞HeLa特异性结合的短肽,进一步与化疗药物结合,为宫颈癌靶向治疗提供新的方法。  相似文献   
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39.
BackgroundOpen pelvic fractures are rare injuries, associated with high patient morbidity and mortality. Few studies have investigated the impact of patient demographics, comorbidities, and injury related factors on complication and mortality rates. The purpose of this study was to: (1) identify the overall incidence of complications and mortality after open pelvic fractures, (2) compare patient factors between those who did and did not develop complications, (3) identify perioperative independent risk factors for complications and mortality.MethodsA query was performed for patients with open pelvic fractures between 2007 and 2017 using the American College of Surgeons National Trauma Data Bank. Patient and injury specific variables were collected and complications were identified using International Classification of Disease Ninth and Tenth edition Codes. Patient demographic and perioperative data was compared using Fisher’s exact test and chi-square test for categorical variables, and Welch’s t-test for continuous variables. Using pooled data from multiple imputations, logistic regressions were used to calculate odds ratios and confidence intervals of independent risk factors for complications.ResultsA total of 19,834 open pelvic fracture cases were identified, with 9622 patients (48.5%) developing at least one complication. Patients who developed complications were older (35.0 vs 38.1 years), and had higher Injury Severity Scores (17.7 vs 26.5), lower Glasgow Coma Scores (14.2 vs 11.7), and a larger proportion presenting with hypotension (21% vs 6.9%). After pooled regression involving 19 factors, these were the strongest independent predictors of inpatient complication and mortality.ConclusionWe report a mortality rate of 14%, with an inclusive complication rate of 48.5%. Evaluating risk factors for morbidity and mortality for this devastating orthopaedic injury provides knowledge of an inherently sparse population.Level of EvidenceLevel II, Retrospective study.  相似文献   
40.
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