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The novel trichlorfon (TCF)-degrading bacterium PA F-3, identified as Bacillus tequilensis, was isolated from pesticide-polluted soils by using an effective screening and domesticating procedure. The TCF biodegradation pathways of PA F-3 were also systematically elucidated. As revealed by high-performance liquid chromatography, the TCF residues in the mineral salt medium demonstrated that PA F-3 can utilize TCF as its sole carbon source and reach the highest degradation of 71.1 % at an initial TCF concentration of 200 mg/L within 5 days. The TCF degradation conditions were optimized using response surface methodology as follows: temperature, 28 °C; inoculum amount, 4 %; and initial TCF concentration, 125 mg/L. Biodegradation treatments supplemented with exogenous carbon sources and yeast extract markedly increased the microbial dry weights and TCF-degrading performance of PA F-3, respectively. Meanwhile, five metabolic products of TCF were identified through gas chromatography/mass spectrometry, and a biodegradation pathway was proposed. Results indicated that deoxidation and dehydration (including the cleavage of the P–C phosphonate bond and the C–O bond) were the preferred metabolic reactions of TCF in this TCF-degrading bacterium.  相似文献   
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以烤烟品种K326为试验材料,在云南、福建和河南三个生态烟区大田种植,自烟叶生理成熟期起至工艺成熟期,分4次采集中部(第11叶位)烟样,对烟叶的δ13 C值、总碳、全氮、光合色素等进行测定,比较不同生态烟区烤烟δ13 C值的分布、生理生态适应性及品质特征。结果表明:(1)三个生态烟区烟叶δ13 C值、总碳、碳氮比、比叶重、叶绿素a、总叶绿素含量均表现为云南福建河南,全氮含量则为河南云南福建,叶绿素b含量为云南河南福建,类胡萝卜素含量为河南福建云南,其中的δ13 C值、总碳、碳氮比、类胡萝卜素含量在福建和云南烟区间较为接近。(2)烟叶δ13 C值与总碳含量在云南呈正相关,在福建、河南呈负相关关系;三个生态烟区烟叶δ13 C值与全氮含量均呈负相关关系;δ13 C值与光合色素含量在云南、河南烟区均呈正相关关系,在福建烟区均呈负相关关系;δ13 C值与烟碱、氮、钾、氯呈负相关关系,与总糖、还原糖呈正相关关系。(3)云南烤烟香韵丰富,刺激性中等,化学成分协调性最好;河南烤烟香气量较高,刺激性较大;福建烤烟在香气量和化学成分协调性方面表现较差。研究发现,烟叶δ13 C值与烟叶的生理特征、品质特征存在紧密联系,用烟叶的δ13 C值、生理指标、化学品质可区分不同生态烟区烤烟香气风格和品质特征。  相似文献   
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目的基于循证医学系统性评价飞行质谱鉴定临床分离真菌的准确度,并与常规方法准确度进行比较。方法检索主要英文数据库PubMed、Cochrane、Web of Science,以及中文数据库CBM、万方、维普、知网数据库,检索飞行质谱鉴定临床分离真菌的原始文献。结果经筛选后纳入19篇文献(6609株真菌),Meta分析结果显示飞行质谱鉴定真菌至种水平正确率为0.9368(95%CI=0.9091~0.9598),常规方法鉴定真菌至种水平正确率为0.9104(95%CI=0.8874~0.9340);对结果进行了亚组分析,主要包括:菌株类型、研究类型、样本处理方法、金标准检测范围、鉴定阈值等;敏感性分析表明结果稳定可靠,Begg和Egger’s结果表明飞行质谱鉴定真菌不存在发表偏倚,常规方法鉴定真菌存在一定发表偏倚。结论基质辅助激光解吸电离-飞行时间质谱系统(MALDI-TOF MS)方法对鉴定临床致病性真菌准确率较高,是临床常规方法的可靠替代方法。  相似文献   
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目的:分析妊娠哺乳期乳腺癌患者的预后情况及其影响因素。方法:将2010年1月至2012年12月期间贵州省贵阳市妇幼保健院、贵州省医科大学和贵州省肿瘤医院收治的妊娠哺乳期乳腺癌患者60例作为研究组,选择同期收治的非妊娠哺乳期乳腺癌患者60例作为对照组,比较两组5年生存率和临床病理特征,并应用单因素和多因素Logistic回归分析患者预后的影响因素。结果:研究组5年生存率为61.67%(37/60),5年无病生存率为46.67%(28/60),均低于对照组的81.67%(49/60),73.33%(44/60)(P0.05)。研究组肿瘤最大直径、腋淋巴结转移率、TNM分期为III期的比例、雌激素受体阳性率、Ki67细胞阳性率≥20%的比例均高于对照组(P0.05),两组孕激素受体阳性率比较无统计学差异(P0.05)。单因素分析显示妊娠哺乳期乳腺癌患者总生存期与肿瘤最大直径、TNM分期、Ki67细胞阳性率≥20%的比例、腋淋巴结转移率有关(P0.05)。多因素Logistic回归分析显示,TNM分期为III期、Ki67细胞阳性率≥20%、腋淋巴结转移是影响妊娠哺乳期乳腺癌患者预后的独立危险因素(P0.05)。结论:妊娠哺乳期乳腺癌患者的预后较差,TNM分期为III期、Ki67细胞阳性率≥20%、腋淋巴结转移是影响患者预后的危险因素,对于临床防治具有重要的启示作用。  相似文献   
347.
Chronic obstructive pulmonary disease(COPD), lung cancer(LC) and tuberculosis(TB) are common chronic lung diseases that generate a large disease burden and significant health care resource use in China. The aim of this study was to quantify spatial patterns and effects of air pollution and meteorological factors on hospitalization of COPD, LC and TB in Beijing. Daily counts of hospitalization for 2010 were obtained from the Beijing Urban Employees Basic Medical Insurance(UEBMI) system.Bayesian hierarchical Poisson regression models were applied to identify spatial patterns of hospitalization for COPD, LC and TB at the district level and explore associations with inhalable particulate matter(aerodynamic diameter 10 μm, PM_(10)), sulfur dioxide(SO_2), nitrogen dioxide(NO_2), mean temperature and relative humidity. There were 18,882, 14,295 and 2,940 counts of hospitalizations for COPD, LC and TB respectively, in Beijing in 2010. Clusters of high relative risk were in different locations for the three diseases. The effect of relative humidity on COPD hospitalization was most significant with a relative risk(RR) of 1.070(95%CI: 1.054, 1.086) per one percent increase. For lung cancer hospitalization, exposure to ambient SO_2 was associated with a RR of 1.034(95%CI: 1.011, 1.058) per μg m~(–3) increase. For tuberculosis, the effect of mean temperature was significant with a RR of 1.107(95%CI: 1.038, 1.180) per °C increase. Risk factors and spatial patterns were different for hospitalization of non-infectious and infectious chronic lung disease in Beijing. Even over a short time period(one year), associations were apparent with air pollution and meteorological factors.  相似文献   
348.
正Dear Editor,Perennial ryegrass (Lolium perenne) is a globally important forage and turf grass species that commonly forms symbiotic associations with the asexual fungal endophyte—Epichlo? festucae var. lolii. Epichlo? endophytes mutualistically interact with host plants by providing major fitness enhancements and protection from both biotic and abiotic stresses  相似文献   
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该研究探讨氰酸盐(cyanate)诱导肾小管上皮细胞氧化应激损伤和促进肾纤维化的作用。氰酸盐作用HK-2肾小管上皮细胞后, CCK8法检测其对细胞活力的影响;倒置显微镜观察细胞形态的改变; DCFH-DA法检测细胞ROS水平;细胞免疫荧光和Western blot分别检测E-cadherin、Fibronectin、α-SMA的表达; Western blot检测TGF-β的表达水平。结果显示, 2 mmol/L氰酸盐明显下调HK-2细胞的活力(P<0.05),细胞形态变为长梭形。氰酸盐作用24 h后, HK-2细胞内ROS水平呈浓度依赖性升高。免疫荧光和Western blot结果均显示,氰酸盐作用24 h后, HK-2的Fibronectin、α-SMA表达升高, E-cadherin表达下降; TGF-β的表达水平随氰酸盐浓度升高而上调(P<0.05)。以上结果表明,氰酸盐诱导肾小管上皮细胞产生过量ROS,上调TGF-β水平促进细胞上皮–间充质细胞转化(epithelia-mesenchymal transition, EMT)。  相似文献   
350.
Initial functional studies have demonstrated that RNA‐binding motif protein 10 (RBM10) can promote apoptosis and suppress cell proliferation; however, the results of several studies suggest a tumour‐promoting role for RBM10. Herein, we assessed the involvement of RBM10 in lung adenocarcinoma cell proliferation and explored the potential molecular mechanism. We found that, both in vitro and in vivo, RBM10 overexpression suppresses lung adenocarcinoma cell proliferation, while its knockdown enhances cell proliferation. Using complementary DNA microarray analysis, we previously found that RBM10 overexpression induces significant down‐regulation of RAP1A expression. In this study, we have confirmed that RBM10 decreases the activation of RAP1 and found that EPAC stimulation and inhibition can abolish the effects of RBM10 knockdown and overexpression, respectively, and regulate cell growth. This effect of RBM10 on proliferation was independent of the MAPK/ERK and P38/MAPK signalling pathways. We found that RBM10 reduces the phosphorylation of CREB via the AKT signalling pathway, suggesting that RBM10 exhibits its effect on lung adenocarcinoma cell proliferation via the RAP1/AKT/CREB signalling pathway.  相似文献   
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