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881.
本研究旨在了解上海口岸输入性传染性肺结核病患者中结核分枝杆菌北京型特征及其对一线抗结核药物的耐药情况,从而正确评估输入性结核病给上海地区带来的公共卫生危害,同时为地区传染性结核病防治策略的制定提供依据。针对2009年1月~2013年5月上海口岸入境体检人员中胸部影像学诊断疑似活动性肺结核病的人群,采集其连续3 d的晨痰分离培养结核分枝杆菌,用MGIT960培养法分析其对抗结核药物(链霉素、异烟肼、利福平、乙胺丁醇、吡嗪酰胺)的耐药情况,用目标缺失多重聚合酶链反应(DTM-PCR )进行结核分枝杆菌北京型分子分型,同时采集其人口学资料。期间共监测到入境外籍疑似活动性肺结核病者193例,其中50例痰液中分离培养到结核分枝杆菌,菌培阳率为25.9%,与我国结核病普查工作中活动性肺结核病菌培阳率(25.9%)相同。分离培养并成功传代、分型的40株结核分枝杆菌中,北京型占57.5%(23/40),显著低于同期上海口岸出境人群中的90.2%(37/41)。输入性结核分枝杆菌北京型主要来自东南亚地区(71.4%,5/7)和西太平洋地区(57.1%,16/28)。一线5种抗结核药物的耐药性检测结果显示,输入性结核分枝杆菌北京型的总耐药率为30.4%(7/23),接近上海口岸出境人群的34.1%。输入性耐多药菌株占2.4%(1/42),分子分型结果显示为非北京型。输入性传染性肺结核病对吡嗪酰胺的耐药率为16.7%,显著高于上海口岸出境人群的2.4%。结果提示,上海口岸输入性肺结核病患者中结核分枝杆菌北京型所占比例显著低于同期出境人群,未发现与性别和年龄相关,未发现输入性结核分枝杆菌北京型对抗结核药物耐药性的显著变化。输入性耐药性结核病带来的公共卫生危害不容忽视,在直接督导下的短程化疗(DOTS)方案中需考虑其高吡嗪酰胺耐药特征。在口岸公共卫生安全风险评估中,需重视输入性结核分枝杆菌北京型与本地流行株的差异。  相似文献   
882.
目的:构建两个高表达人TNFα和IL-1β细胞系,建立抗炎药物筛选细胞模型。方法:运用PCR的方法从载体pCMVSport-TNFα和p CMVSport-IL1β上扩增目的基因,以亚克隆方法将目的基因分别插入真核表达载体pcDNA3.1和pFLAG-CMV中,用单酶切、PCR扩增和基因测序的方法鉴定重组效果,然后将重组成功的质粒转入HEK293细胞系内,挑选能够稳定表达并遗传的单克隆细胞株,用蛋白免疫印迹(Western blot)法分析其表达效果。结果:三种鉴定方法均显示重组质粒构建成功。Western blot结果显示,细胞株T3、T4均能较高表达炎症因子TNF-α;细胞株I2、I3、I5均能较高表达炎症因子IL-1β。结论:成功构建了TNFα和IL-1β靶标的药物筛选细胞模型,为筛选具有抗炎作用的中药提供了一个新平台。  相似文献   
883.
目的:对比两种不同的四联疗法对幽门螺杆菌根除失败后的根除率,选择可以有效弥补传统三联疗法的幽门螺杆菌根除失败措施的四联疗法。方法:选择2010年8月到2012年8月期间在我院住院治疗的幽门螺杆菌根除失败后患者90例作为研究对象。随机分为实验组和对照组,实验组的患者采取序贯疗法,对照组的患者采取标准四联疗法。对比两组的根除率以及临床疗效。结果:实验组患者的根除率为86.7%,对照组患者根除率为51.0%;实验组患者的临床总有效率为95.6%,对照组的临床有效率为77.8%;实验组的不良反应的总发生率为4.4%,对照组不良反应总发生率为20.0%。两组比较差异明显,P均0.05,具有统计学意义。结论:序贯疗法对幽门螺杆菌根除失败后的根除率以及疗效高于标准四联疗法。  相似文献   
884.
利用RNA-seq技术分析淹水胁迫下转BnERF拟南芥差异表达基因   总被引:1,自引:0,他引:1  
为探究淹水胁迫下BnERF调节的耐淹防御相关途径,应用RNA-seq技术,对淹水6小时后的拟南芥(Arabidopsis thaliana)野生型(WT)和转BnERF株系(E33)幼苗进行基因表达分析。结果表明,淹水3天后,E33表现出较强的耐淹性,地上部生长状况和根系发育均明显强于野生型。E33幼苗未淹水处理时相对于野生型单独上调的基因有9个,4个为膜结合蛋白,其中2个参与MAPK级联途径,其它5个参与氧化胁迫及水分调节途径;与未淹水野生型相比,无论是未淹水处理还是淹水6小时后的E33幼苗中缺氧响应、抗氧化防护及细胞、器官发育相关基因的表达量均上调。另外,淹水6小时后E33的差异基因并未完全覆盖淹水6小时后野生型的差异基因;E33幼苗中缺氧响应、氧化胁迫响应、能量的产生与转变、乙醇代谢途径中的基因以及乙烯响应因子基因的表达量都明显高于野生型。上述结果表明,BnERF直接或间接调节植物的淹水胁迫相关生理代谢途径,参与淹水胁迫的防御过程。  相似文献   
885.
哺乳动物骨骼肌由各种不同类型的肌纤维镶嵌而成,不同类型肌球蛋白重链的表达是造成不同类型肌纤维的主要原因.目前已知的肌球蛋白重链家族包含8种亚型,其中长白猪骨骼肌My HC-Ⅱb的表达量显著高于中国地方猪,然而造成这种差异的分子机制未见报道.本研究用荧光定量PCR证明了长白猪背最长肌中My HC-Ⅱb m RNA的表达量显著高于莱芜猪(P=0.013).删除实验结果表明,从转录起始位点上游-1024 bp删除到-187 bp之后,My HC-Ⅱb表达量显著下降,分析发现,在这段启动子区域内存在3个E-box序列;分别突变这3个E-box序列后,My HC-Ⅱb启动子驱动的荧光素酶活性显著下降(P=0.036).另外,在My HC-Ⅱb上游启动子区?1398 bp处发现一个GT的突变,所检测的64头莱芜猪在该位点全部为GG型,65头长白猪中13头为GG型,16头为TT型,36头为GT型.在C2C12细胞系中的转染实验结果显示,G突变为T之后有增加My HC-Ⅱb表达的趋势.Western blot的结果表明,转录因子Myo D在两猪种间表达差异不显著(P=0.136),而Myf-5在长白猪中的表达量极显著高于其在莱芜猪中的表达量(P=0.0036).这些数据表明,Myf-5是造成猪My HC-Ⅱb基因m RNA上调表达的重要因素之一.  相似文献   
886.
BackgroundThe second wave of avian influenza H7N9 virus outbreak in humans spread to the Guangdong province of China by August of 2013 and this virus is now endemic in poultry in this region.MethodsFive patients with H7N9 virus infection admitted to our hospital during August 2013 to February 2014 were intensively investigated. Viral load in the respiratory tract was determined by quantitative polymerase chain reaction (Q-PCR) and cytokine levels were measured by bead-based flow cytometery.ResultsFour patients survived and one died. Viral load in different clinical specimens was correlated with cytokine levels in plasma and broncho-alveolar fluid (BALF), therapeutic modalities used and clinical outcome. Intravenous zanamivir appeared to be better than peramivir as salvage therapy in patients who failed to respond to oseltamivir. Higher and more prolonged viral load was found in the sputum or endotracheal aspirates compared to throat swabs. Upregulation of proinflammatory cytokines IP-10, MCP-1, MIG, MIP-1α/β, IL-1β and IL-8 was found in the plasma and BALF samples. The levels of cytokines in the plasma and viral load were correlated with disease severity. Reactivation of herpes simplex virus type 1(HSV-1) was found in three out of five patients (60%).ConclusionExpectorated sputum or endotracheal aspirate specimens are preferable to throat swabs for detecting and monitoring H7N9 virus. Severity of the disease was correlated to the viral load in the respiratory tract as well as the extents of cytokinemia. Reactivation of HSV-1 may contribute to clinical outcome.  相似文献   
887.
BackgroundNeonatal sepsis (NS) is a life-threatening disorder and an important cause of morbidity and mortality in neonates. Previous studies showed that interleukin 8 (IL-8) may effectively and rapidly diagnose NS.ObjectiveWe conducted the systematic review and meta-analysis to investigate the diagnostic value of the IL-8 in NS.MethodsThe literature was searched in PUBMED, EMBASE, Cochrane Library, CNKI, VIP and other Chinese Medical Databases during October 1998 to January 2014 using set search criteria. Each included study was evaluated by quality assessment of diagnostic accuracy studies tool. Two investigators independently extracted the data and study characteristics, and disagreements, if any, were resolved by consensus. Meta-disc software was used to calculate the pooled sensitivity, specificity and summary diagnostic odds ratio (SDOR), I² or Cochrane Q to test heterogeneity, and meta-regression to investigate the source of heterogeneity. Funnel plots were used to test the potential presence of publication bias. False-positive report probability (FPRP) was calculated to confirm the significance of the results.ResultsEight studies (548 neonates) were included in this meta-analysis. The pooled sensitivity and specificity of IL-8 were 0.78 and 0.84, respectively, which had moderate accuracy in the diagnosis of NS. The pooled diagnostic odds ratio (DOR) and area under curve (AUC) was 21.64 and 0.8908 (Q*=0.8215), respectively. The diagnostic threshold analysis showed that there was no threshold effect. The meta-regression analysis showed the cut-off, QUADAS and onset time have no effect on the heterogeneity. The funnel plots showed the existence of publication bias.ConclusionMeta-analysis showed IL-8 had a moderate accuracy (AUC=0.8908) for the diagnosis of NS. IL-8 is a helpful biomarker for early diagnosis of NS. However, we should combine the results with clinical symptoms and signs, laboratory and microbial results.  相似文献   
888.
889.
About 25% of European livestock intake is based on permanent and sown grasslands. To fulfill rising demand for animal products, an intensification of livestock production may lead to an increased consumption of crop and compound feeds. In order to preserve an economically and environmentally sustainable agriculture, a more forage based livestock alimentation may be an advantage. However, besides management, grassland productivity is highly vulnerable to climate (i.e., temperature, precipitation, CO2 concentration), and spatial information about European grassland productivity in response to climate change is scarce. The process-based vegetation model ORCHIDEE-GM, containing an explicit representation of grassland management (i.e., herbage mowing and grazing), is used here to estimate changes in potential productivity and potential grass-fed ruminant livestock density across European grasslands over the period 1961–2010. Here “potential grass-fed ruminant livestock density” denotes the maximum density of livestock that can be supported by grassland productivity in each 25 km × 25 km grid cell. In reality, livestock density could be higher than potential (e.g., if additional feed is supplied to animals) or lower (e.g., in response to economic factors, pedo-climatic and biotic conditions ignored by the model, or policy decisions that can for instance reduce livestock numbers). When compared to agricultural statistics (Eurostat and FAOstat), ORCHIDEE-GM gave a good reproduction of the regional gradients of annual grassland productivity and ruminant livestock density. The model however tends to systematically overestimate the absolute values of productivity in most regions, suggesting that most grid cells remain below their potential grassland productivity due to possible nutrient and biotic limitations on plant growth. When ORCHIDEE-GM was run for the period 1961–2010 with variable climate and rising CO2, an increase of potential annual production (over 3%) per decade was found: 97% of this increase was attributed to the rise in CO2, -3% to climate trends and 15% to trends in nitrogen fertilization and deposition. When compared with statistical data, ORCHIDEE-GM captures well the observed phase of climate-driven interannual variability in grassland production well, whereas the magnitude of the interannual variability in modeled productivity is larger than the statistical data. Regional grass-fed livestock numbers can be reproduced by ORCHIDEE-GM based on its simple assumptions and parameterization about productivity being the only limiting factor to define the sustainable number of animals per unit area. Causes for regional model-data misfits are discussed, including uncertainties in farming practices (e.g., nitrogen fertilizer application, and mowing and grazing intensity) and in ruminant diet composition, as well as uncertainties in the statistical data and in model parameter values.  相似文献   
890.

Background

Influenza H7N9 and H1N1pdm can cause severe human infections. It is important to investigate the distinguishing clinical features between these two diseases. Several studies have compared the differences in general, however, age and gender adjusted comparisons may be more useful and informative to the health professionals.

Methods

A total of 184 severe H1N1pdm patients and 37 severe H7N9 patients from Jiangsu Province were included in this analysis to perform age and gender adjusted comparison of clinical features.

Results

After adjusting age and gender, no significant differences in chronic medical conditions or treatment were found between severely ill patients with H7N9 and H1N1pdm. Severely ill patients with H7N9 had significantly longer interval from onset of illness to neuraminidase inhibitor treatment and to death. They were more likely to have complications such as acute respiratory distress syndrome (ARDS), liver and renal dysfunctions, and had a significantly higher risk of death.

Conclusion

Our results suggests that age and gender should be adjusted as important confounding factors when comparing the clinical features between severe H7N9 and H1N1pdm patients to avoid any misunderstanding regarding the differences between these two diseases particularly in terms of clinical severity and prognosis.  相似文献   
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