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41.
目的分析贵阳地区儿童重症社区获得性肺炎支气管肺泡灌洗液(BALF)病原学分布及耐药特点。方法收集989例重症社区获得性肺炎患儿临床资料,将支气管肺泡灌液采用支气管镜取出进行细菌培养、病毒以及肺炎支原体(MP)检测。结果(1)989例重症社区获得性肺炎患儿病原检出阳性716例,阳性率72.40%,细菌、病毒、支原体检出率分别33.27% (329例)、22.45%(222例)、31.45%(311例)。(2)细菌感染中的肺炎链球菌、金黄色葡萄球菌为最为常见的革兰阳性菌株(G+);而肺炎克雷伯菌、大肠埃希菌为最为常见的革兰阴性菌株(G-)。培养菌株对青霉素类、红霉素、第1、2、3代头孢类抗生素有较高的耐药性,对头孢吡肟、拉氧头孢、哌拉西林、左氧氟沙星有较高的敏感性,对亚胺培南、万古霉素、利奈唑烷均无耐药发生。(3)病毒感染检出222例,其中呼吸道合胞病毒131例,腺病毒检测49例,流感病毒6例(A型2例,B型4例),副流感病毒36例(1型3例、2型4例、3型29例),病毒检出率以0~12月龄组最高,RSV、ADV感染主要集中在冬春季节。(4)肺炎支原体检出阳性率31.45%(311例),肺炎支原体检出率以3~5岁组最高。结论贵阳地区重症肺炎中肺炎克雷伯杆菌、肺炎链球菌、大肠埃希菌、金黄色葡萄球菌为重要的细菌病原。重要病毒为腺病毒和呼吸道病毒为主,1~12月龄组的病毒感染检出率比较高。 相似文献
42.
Li Han-yun Ye Yin-dong Zhang Qi-jun Du Cun-hao Li Hui-ming Yin Li 《Bulletin of environmental contamination and toxicology》2022,109(2):409-416
Bulletin of Environmental Contamination and Toxicology - In this study, a composite algaecide containing flocculants and Cinnamomum. camphora leaves extracts (CCCLE) were synthesized. The... 相似文献
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J Phua E S C Koay D Zhang L K Tai X L Boo K C Lim T K Lim 《The European respiratory journal》2006,28(4):695-702
Levels of the soluble form of the triggering receptor expressed on myeloid cells (sTREM)-1 are elevated in severe sepsis. However, it is not known whether sTREM-1 measurements can distinguish milder bacterial infections from noninfectious inflammation. The present authors studied whether serum sTREM-1 levels differ in community-acquired pneumonia, exacerbations of chronic obstructive pulmonary disease (COPD), asthma and controls, and whether sTREM-1 may be used as a surrogate marker for the need for antibiotics. Serum sTREM-1 levels in 150 patients with pneumonia, COPD and asthma exacerbations and 62 healthy controls were measured. Serum sTREM-1 levels were significantly elevated in pneumonia (median 295.2 ng x mL(-1)), COPD (280.3 ng x mL(-1)) and asthma exacerbations (184.0 ng x mL(-1)) compared with controls (83.1 ng x mL(-1)). Levels were higher in pneumonia and Anthonisen type 1 COPD exacerbations than in type 2 and 3 COPD and asthma exacerbations. The area under the receiver operating characteristics curve for sTREM-1 as a surrogate marker for the need for antibiotics was 0.77. Serum levels of the soluble form of the triggering receptor expressed on myeloid cells-1 were elevated predominantly in pneumonia and Anthonisen type 1 COPD exacerbations versus type 2 and 3 chronic obstructive pulmonary disease exacerbations, asthma and controls. Serum levels of the soluble form of the triggering receptor expressed on myeloid cells-1 has moderate but insufficient accuracy as a surrogate marker for the need for antibiotics in lower respiratory tract infections. 相似文献
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目的建立泰泽氏病原体(Ty)纯化方法,获得纯的菌体供抗原研究,为ELISA诊断抗原的制备提供依据;并尝试建立Ty隐性感染血清学抗原检查方法。方法选择特异性抗体包被磁珠,从感染大鼠肝脏中富集和纯化Ty;用SDS-PAGE和Western blot技术考察纯化Ty的蛋白和抗原图谱;同时用免疫磁珠分离技术(IMS)直接检查隐性感染大鼠肠道上皮细胞内的Ty。结果用辛酸-硫酸铵纯化的Ty单克隆抗体M5以0·5μg/107beads以上浓度包被抗IgG抗体预结合的磁珠4h,可最大效率地富集Ty;分离反应进行1h,敏感性达到103菌体/mL;吖啶黄染色镜检法可以直接、快速地观察到结合于磁珠上的细菌;抗原分析表明,IMS较好地去除了肝组织和真核细胞成分,纯化的Ty RJ株具有3个免疫优势的抗原成分,相对分子质量(Mr)分别为160×103、116×103、55×103;此外,IMS法可直接从隐性感染大鼠盲肠上皮细胞中检测到少量寄生的Ty。结论用IMS技术可有效地富集和纯化Ty,并可以作为Ty隐性感染血清学抗原检查的候选方法。 相似文献
48.
目的研究离体培养的海马神经元LKB1表达下调对于神经元微小兴奋性突触后电流(mEP-SC)的影响。方法选用17d的胚胎大鼠培养海马神经元,分别用电穿孔的方法转染CAG-RE质粒和LKB1RNAi质粒,培养10~12d后进行电生理记录,选用全细胞膜片钳方式及自由记录模式,细胞外液加TTX阻断动作电位,加Bicucullin抑制GABA电流,记录神经元的mEPSC,比较2组神经元的mEPSC频率和幅度的差别。结果转染CAG-RE的神经元mEPSC幅度平均为25.6pA,频率平均为(5.21±0.25)Hz,是基线的99.8%;转染LKB1RNAi的神经元mEPSC幅度平均为35.1pA,频率平均为(5.79±0.27)Hz,是基线的127.1%;比较2组间频率、幅度变化,差别有显著性意义(P<0.05)。结论LKB1基因表达下调增强了培养海马神经元突触传递的效率。 相似文献
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Body weight and comorbidity predict mortality in COPD patients treated with oxygen therapy. 总被引:1,自引:0,他引:1
The aim of this study was to investigate the association between clinical variables and all-cause and respiratory mortality in patients with chronic obstructive pulmonary disease (COPD) undergoing long-term oxygen therapy (LTOT). The authors retrospectively studied a historic cohort of 128 patients with COPD (126 males, mean age+/-SD 68.9+/-9.7 yrs, body mass index (BMI) 25.1+/-4.5 kg.m-2, and forced expiratory volume in one second 25.4+/-8.8% predicted), who were being treated with long-term oxygen therapy in a tertiary teaching hospital between 1992 and 1999. Comorbidity, assessed with the Charlson Index, was present in 38% of the patients. Vital status and cause of death were assessed through the population death registry. A total of 78 patients (61%) had died by the end of follow-up. Three-year survival was 55%. Death was due to respiratory causes in 77% of cases. On Cox analysis, BMI<25 kg.m-2, comorbid conditions, age>or=70 yrs and cor pulmonale were associated with all-cause mortality. The BMI and comorbidity were the only significant predictive factors when the analysis was restricted to respiratory mortality. In conclusion, body mass index<25 kg.m-2 and comorbidity were predictors of all-cause and respiratory mortality in a cohort of chronic obstructive pulmonary disease patients treated with long-term oxygen therapy. These factors should be taken into account when considering the management and prognosis of these patients. 相似文献