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51.

Background

Recent studies on the association between CD14-159C/T polymorphism and sepsis showed inconclusive results. Accordingly, we conducted a comprehensive literature search and a meta-analysis to determine whether the CD14-159C/T polymorphism conferred susceptibility to sepsis or was associated with increased risk of death from sepsis.

Methodology

Data were collected from the following electronic databases: PubMed, Embase, Medline, Web of Knowledge, and HuGE Navigator, with the last report up to June 15, 2012. The odds ratio (OR) and 95% confidence interval (CI) were used to assess the strength of association. We summarized the data on the association between CD14-159C/T polymorphism and sepsis in the overall population and subgroup by ethnicity and sepsis subtype.

Principal Findings

A total of 16 studies on sepsis morbidity (1369 cases and 2382 controls) and 4 studies on sepsis mortality (731 sepsis patients) met the inclusion criteria for meta-analysis. Overall analysis showed no strong evidences of association with sepsis susceptibility under any genetic model. However, slight associations were found in Asian populations (dominant model: OR = 1.38, 95%CI = 0.96–1.98, P = 0.08) and septic shock patients (dominant model: OR = 1.72, 95%CI 1.05–2.83, P = 0.03; allelic model: OR = 1.52, 95%CI 1.09–2.12, P = 0.01) in the stratified analysis. Moreover, there was borderline association between CD14-159C/T and sepsis mortality under the dominant genetic model (OR = 1.44, 95%CI = 0.98–2.11, P = 0.06).

Conclusions/Significance

This meta-analysis suggests that the CD14-159C/T polymorphism may not be a significant susceptibility factor in the risk of sepsis and mortality. Only weak associations were observed in Asian populations and septic shock patients. More studies based on larger sample sizes and homogeneous sepsis patients are needed to confirm these findings.  相似文献   
52.
53.
神农架龙门河地区基于植被的GAP分析   总被引:9,自引:0,他引:9       下载免费PDF全文
基于MapInfoProfessional 6 .0软件和野外调查所积累的资料 ,首先找出最佳“投资 效益比”的珍稀濒危物种密集分布区。随后 ,利用GAP分析的方法 ,对龙门河地区现状植被类型图、管理规划图、珍稀濒危物种密集分布区图进行了叠加分析 ,结果表明 :该地区规划管理的gap主要由 3部分组成 ,即原管理方法中不限制人为干扰的区域、原保护区域内没有包含的自然植被类型所属分布区、珍稀濒危物种密集分布区中没有禁止人为干扰的区域。其总面积为 1 736hm2 ,占龙门河地区总面积的 36 .81 %。综合考虑对植物多样性的保护及当地居民的生活所需 ,为该地区今后的管理重点提出了合理化建议  相似文献   
54.
Abstract

Introduction: The aim of the study was to explore the association between the vitamin D pathway gene variations and the bone biomarkers response to calcium and low dose calcitriol supplementation in postmenopausal Chinese women.

Methods: A total of 110 healthy postmenopausal Chinese women (61.51?±?6.93?years) were enrolled. The participants were supplemented with calcium (600?mg/d) and calcitriol (0.25?μg/d), for 1?year. Four biomarkers, serum levels of beta C-terminal cross-linked telopeptides of type I collagen (β-CTX), amino-terminal propeptide of type I collagen (P1NP), parathyroid hormone (PTH) and 25-hydroxyvitamin D [25(OH)D] were measured at baseline and 12-month follow-up. Multivariate regression models were established to explore the statistical association between the change rate of the four biomarkers and 15?key genes within the vitamin D metabolic pathway.

Results: This exclusion process left 98 participants for analysis. Serum levels of P1NP, β-CTX and PTH were significantly decreased at the 12-month follow-up (all p?<?0.05). Serum 25(OH)D level had no significant change (p?>?0.05). No association was found between the vitamin D pathway gene polymorphisms and bone biomarkers response to calcium and low dose calcitriol supplementation.

Conclusions: Genetic background of postmenopausal Chinese women might not influence supplemental response of the biomarkers to calcium and low dose calcitriol.  相似文献   
55.
陈玥  周景文  陈坚 《生物工程学报》2021,37(6):1827-1844
维生素C是一种人体必需的维生素,在食品制药等领域拥有巨大的市场。工业上维生素C主要以微生物发酵生产的2-酮基-L-古龙酸为前体,然后通过内酯化反应获得。微生物发酵中,山梨糖途径和葡萄糖酸途径因为转化率高一直是研究的热点。文中从维生素C生物合成相关脱氢酶的角度阐述了:山梨糖途径和葡萄糖酸途径中关键脱氢酶在定位、底物谱、辅因子和电子传递上的特点;山梨糖途径和葡萄糖酸途径中面临的主要问题和改造策略等。最后讨论了维生素C生物合成中山梨糖途径和葡萄糖酸途径可能的研究方向。  相似文献   
56.
Microsatellites are widely distributed throughout nearly all genomes which have been extensively exploited as powerful genetic markers for diverse applications due to their high polymorphisms. Their length variations are involved in gene regulation and implicated in numerous genetic diseases even in cancers. Although much effort has been devoted in microsatellite database construction, the existing microsatellite databases still had some drawbacks, such as limited number of species, unfriendly export format, missing marker development, lack of compound microsatellites and absence of gene annotation, which seriously restricted researchers to perform downstream analysis. In order to overcome the above limitations, we developed PSMD (Pan‐Species Microsatellite Database, http://big.cdu.edu.cn/psmd/ ) as a web‐based database to facilitate researchers to easily identify microsatellites, exploit reliable molecular markers and compare microsatellite distribution pattern on genome‐wide scale. In current release, PSMD comprises 678,106,741 perfect microsatellites and 43,848,943 compound microsatellites from 18,408 organisms, which covered almost all species with available genomic data. In addition to interactive browse interface, PSMD also offers a flexible filter function for users to quickly gain desired microsatellites from large data sets. PSMD allows users to export GFF3 formatted file and CSV formatted statistical file for downstream analysis. We also implemented an online tool for analysing occurrence of microsatellites with user‐defined parameters. Furthermore, Primer3 was embedded to help users to design high‐quality primers with customizable settings. To our knowledge, PSMD is the most extensive resource which is likely to be adopted by scientists engaged in biological, medical, environmental and agricultural research.  相似文献   
57.
58.
狭叶柴胡的抗过敏活性及其有效成分   总被引:4,自引:0,他引:4  
本文以compound 48/80在体外诱导大鼠腹腔肥大细胞释放组胺,评价狭叶柴胡及其成分的抗过敏活性。狭叶柴胡醇提物及正丁醇部分(100μg/mL)、乙酸乙酯及水部分(10,100μg/mL)显著减少组胺释放,以乙酸乙酯部分的作用最强,狭叶柴胡挥发油(100μg/mL)对组胺释放呈现一定的促进作用。从乙酸乙酯部分分离得到异鼠李素和槲皮素两种主要化合物,均显著抑制组胺释放,表明黄酮为狭叶柴胡抗过敏作用的有效成分。  相似文献   
59.
60.
降解组测序技术在植物miRNA研究中的应用   总被引:2,自引:0,他引:2  
董淼  黄越  陈文铎  徐涛  郎秋蕾 《植物学报》2013,48(3):344-353
目前, 利用芯片技术和miRNA测序可快速、准确地检测到物种中所含有的miRNA。随着越来越多的miRNA被发现, miRNA靶基因的确定已成为研究miRNA生物学功能的关键。传统的miRNA靶基因的寻找主要依赖生物信息学预测、AGO蛋白免疫共沉淀和荧光素酶法等。随着高通量测序技术的持续革新, 出现了一种新的miRNA靶基因的检测方法, 即降解组测序(degradome sequencing)法, 该方法拥有高通量测序技术、生物信息学分析和RACE验证三者的优势, 并已成功应用于拟南芥(Arabidopsis thaliana)、水稻(Oryza sativa)和小立碗藓(Physcomitrella patens)等模式植物miRNA靶基因的检测。基于已发表的相关文献和联川生物降解组测序平台, 该文对降解组测序技术应用于植物miRNA靶基因的研究进展及其实验原理进行了综述, 同时对运用该技术可进行的更深入研究进行了讨论。  相似文献   
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