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诺木洪河流域地下水水化学特征及演化规律研究
Hydrochemistry characteristics and evolution of groundwater in Nomhon River Basin in Qinghai

杨炳超,,,,
- , 2016,
Abstract: 【目的】对青海省诺木洪河流域地下水水化学特征及演化规律进行研究,为合理开发和保护该地区地下水提供指导。【方法】采集诺木洪河流域具有代表性的水样58个,测定水样中的Na+、K+、Ca2+、Mg2+、HCO3-、Cl-、SO42-、CO32-、矿化度等指标,在此基础上,运用Piper 三线图图示法和离子比例系数法,系统研究了地下水水化学的空间分布特征与演化规律。【结果】①由南而北,研究区地下水水化学特征呈环带状分布,主要从HCO3·SO4·Cl-Na·Mg·Ca、HCO3·Cl-Mg·Na型向SO4·Cl-Na 、Cl-Na型演化转变,矿化度由小于1 g/L增至10 g/L以上。②溶滤作用、蒸发浓缩作用、阳离子交换作用是控制研究区地下水水化学演化的主要水化学作用,沿地下水径流方向,主要发生了石盐、石膏和长石的溶解反应、方解石和白云石的沉淀反应及Ca-Na 阳离子交换反应。【结论】诺木洪河流域地下水水化学特征受水循环特征影响,戈壁滩与冲洪积平原区地下水水化学类型以HCO3·Cl-Na·Mg为主,矿化度小于1 g/L,为淡水;冲湖积平原区地下水水化学类型以Cl-Na为主,矿化度大于1 g/L,为咸水甚至卤水。
【Objective】Hydrochemistry characteristics and evolution of groundwater in Nuomuhong River Basin were studied to provide guidance for reasonable application and protection of groundwater.【Method】Fifty-eight water samples were collected from the basin and Na+,K+,Ca2+,Mg2+,HCO3-,Cl-,SO42-,CO32-,and salinity were measured.The spatial variation of the hydrochemistry characteristics and evolution of groundwater were studied based on piper diagram and ratio coefficients of main ions.【Result】① From south to north,the hydrochemistry characteristics of groundwater were distributed in ring zones.The species changed gradually from HCO3·SO4·Cl-Na·Mg·Ca,HCO3·Cl-Na·Mg to SO4·Cl-Na and Cl-Na.Salinity increased from less than 1 g/L to more than 10 g/L.② The hydrochemistry processes were mainly controlled by lixiviation,evaporation and ion exchange.Along the direction of groundwater,precipitation between calcite and dolomite,dissolution of gypsum,plagioclase and potassium feldspar,and cation exchange between Ca2+ and Na+ were observed.【Conclusion】The hydrochemistry characteristics of groundwater were affected by water cycle in this area.HCO3·Cl-Na·Mg was the main hydrochemistry type in Gobi and alluvial plain with salinity of less than 1 g/L.Cl-Na was the main hydrochemistry type in lake plain with salinity of more than 1 g/L
盐度对草鱼生长和肌肉品质的影响
勤 ?,星星,冷向军,
水产学报 , 2007, DOI: 10.3724/SP.J.00001
Abstract: 为考察盐度对草鱼生长和肌肉品质的影响,设置盐度为0(对照组),5.0、7.5、10.0的4个水平,饲养平均体重为(725±42)g的草鱼30d,测定草鱼生长性能、肌肉营养成分和肌肉物理性能指标。结果表明,在0、5.0、7.5盐度中草鱼生长良好,成活率均为100%,增重率为27.6%、28.3%、26.4%,但在盐度为10.0的水体中,草鱼成活率和增重率均极显著降低(p<0.01),仅为60%、4.5%,而饲料系数显著上升(p<0.01);在肌肉基本营养成分方面,盐度为0,5.0,7.5各组草鱼肌肉水分、粗蛋白、灰分含量无显著差异,但盐度为10的草鱼组肌肉水分含量显著增加,粗蛋白含量降低。经过不同盐度水体暂养后,草鱼肌肉中脂肪含量显著减少(p<0.01),胶原蛋白含量增加,肌纤维耐折力提高,肌纤维直径减小,而盐度对肌肉失水率的影响则呈现不同的特点,其中5.0、10.0盐度使肌肉失水率显著上升(p<0.01),而7.5盐度则使肌肉失水率显著下降(p<0.01)。上述结果表明,半咸水暂养草鱼可改善其肌肉品质,适宜的盐度值为7.5。表4参28
重粉尘环境敞开循环冷却水系统水稳剂的研制
,怀义,徐承明
腐蚀科学与防护技术 , 2002,
Abstract: 针对重粉尘环境发电厂敞开循环冷却水系统的工艺条件,通过旋转腐蚀挂片试验、静态阻垢试验、动态污垢热阻及腐蚀速度测试等一系列试验,研制了其相应的水稳剂.
BIEA对铝在盐酸中的缓蚀作用研究
俞敦义,淑红,
腐蚀科学与防护技术 , 2000,
Abstract: 通过腐蚀失重实验和极化曲线测试,研究合成药剂N、N、N′、N′四(2甲基苯并咪唑)1、2-乙二胺(简称BIEA)分子对铝在1.5mol/LHCl溶液中的缓蚀性能,分析其作用机理,并研究BIEA与丁胺、庚胺的协同作用.结果表明对铝在1.5mol/LHCl溶液中BIEA是一种性能良好的缓蚀剂.
室外膨胀超薄型氯醚树脂钢结构防火涂料
郭晓军,,张其滨,
涂料工业 , 2005,
Abstract: ?以氯醚树脂、丙烯酸树脂为成膜物质,添加复合阻燃发泡材料,研制了一种室外钢结构用超薄型防火涂料。由该涂料制得的涂层遇火发泡膨胀,具有一定高度的密实微孔状阻烯层,从而延长钢结构的耐火极限。该涂料具有良好的耐候性、阻燃性。
乌司他丁减轻老年大鼠髋部骨折后肺损伤程度的实验研究
,刘浩,,
- , 2017,
Abstract: 目的 探讨乌司他丁减轻髋部骨折后肺损伤的作用及相关机制。方法 将24只10月龄SD大鼠随机分为对照组、实验组及干预组,每组8只,后2组制成左侧髋部骨折,其中干预组在造模前给予尾静脉注射乌司他丁50 000 U/kg。造模24 h后处死各组大鼠,检测各组实验动物血清中线粒体DNA(mtDNA)水平,肺泡灌洗液中肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)水平,肺组织中toll样受体-9(TLR9)、转录因子NF-κB表达水平,肺组织干湿质量比(W/D)、病理评分情况。结果 实验组大鼠血清中mtDNA水平,肺泡灌洗液中TNF-α、IL-6水平,肺组织中TLR9、NF-κB表达水平,肺组织W/D、病理评分情况均高于对照组( P<0.05);干预组大鼠血清中mtDNA水平,肺泡灌洗液中TNF-α、IL-6水平,肺组织中TLR9、NF-κB表达水平,肺组织W/D、病理评分情况均较实验组下降( P<0.05),但均未恢复至对照组水平( P<0.05)。结论 乌司他丁可能通过减少髋部骨折释放的mtDNA,进而降低肺组织中TLR9、NF-κB表达及下游的炎症因子水平,最终达到保护肺功能的作用。
Objective To investigate the protective effect and its possible mechanism of ulinastatin on lung injury caused by hip fracture. MethodsTotal 24 SD rats were randomly divided into control, hip fracture and hip fracture+ulinastatin groups (n=8). The rats of hip fracture and hip fracture+ulinastatin groups made the left hip fracture. The tail vein of rats of hip fracture+ulinastatin group were injected with 50 000 U/kg ustodin before made fracture model. Killed rats 24 h after mold building. Serum mtDNA, tumor necrosis factor-α (TNF-α) and interleukin (IL)-6 in bronchoalveolar lavage fluid, Toll like receptor-9 (TLR9) and nuclear factor (NF)-κB protein expression in lung tissue, wet/dry ratio and pathological scores of lung were detected in all three groups. ResultsSerum mtDNA, TNF-α and IL-6 in bronchoalveolar lavage fluid, TLR9 and NF-κB protein expressions in lung tissue, wet/dry ratio and pathological scores of lung in hip fracture group were significantly higher than those in control group ( P<0.05). Ulinastatin significantly reduced the levels of serum mtDNA, TNF-α and IL-6 in bronchoalveolar lavage fluid, TLR9 and NF-κB protein expressions in lung tissue, as well as wet/dry ratio and pathological scores of lung ( P<0.05). ConclusionUlinastatin might could provide protection on lung injury in hip fracture, and mtDNA-TLR9-NF-κB pathway may play the role of reducing inflammatory level in the process.
长链非编码RNAH19促进结直肠癌细胞株增殖的研究
,裴振,永芝,
- , 2017,
Abstract: 目的 研究长链非编码RNA(long non-coding RNA, lncRNA) 家族分子母源性印迹基因19 转录因子(H19 )在结直肠癌组织及细胞株中的表达情况及其对人结直肠癌SW620细胞增殖的影响。方法 采用实时荧光定量PCR(qRT-PCR)检测20例结直肠癌组织及其癌旁组织,以及结直肠癌细胞株SW480、HCT116、SW620和正常结直肠上皮NCM460细胞中H19的表达。结直肠癌SW620细胞分别转染H19 siRNA(si-H19 组) 和阴性对照序列(si-NC组) ,分别采用流式细胞技术、细胞克隆形成实验和CCK8检测两组细胞的增殖情况。qRT-PCR和Western blot检测两组细胞G1/S-特异性周期蛋白-D1(CyclinD1)和细胞周期素依赖激酶(cyclin dependent kinase 4, CDK4)的表达情况。结果 与癌旁组织和正常结直肠上皮NCM460细胞相比较,结直肠癌组织和细胞株中H19的表达水平升高( P<0.05);si-H19组细胞H19表达水平低于si-NC组,且细胞活力和细胞克隆数均低于si-NC组,以上差异均有统计学意义( P<0.05);同时,相较于si-NC组,si-H19组CyclinD1和CDK4基因和蛋白的表达受到了明显抑制( P<0.05)。结论 结直肠癌组织及细胞株中H19 呈高表达,沉默H19 表达能明显抑制结直肠癌细胞的增殖能力,为结直肠癌的靶向治疗提供了潜在策略。
ObjectiveTo determine the expression level of long non-coding RNA (lncRNA) imprinted maternallyexpressed transcript (H19) in colorectal cancer tissues and its effect on proliferation of colorectal cancer SW620 cells. MethodsReal-time quantitative PCR (qRT-PCR) was applied to detect the expression of H19 in 20 paired tumor tissues and adjacent normal tissues, and in normal NCM460 cells and colorectal cancer SW480, HCT116 and SW620 cells. The specific small interfering RNA for H19 (si-H19 group) or negative control sequence (si-NC group) were transfected into SW620 cells. Proliferation of the transfected cells was detected using flow cytometry, CCK8 assay and clone formation experiment. The expressions of CyclinD1 and cyclin dependent kinase 4 (CDK4) were detected by qRT-PCR and Western blot. ResultsThe expression levels of H19 in colorectal cancer tissues and cells were higher compared with those in adjacent normal tissues and normal NCM460 cells. Lower H19 level, cell activities and cell clone numbers were found in si-H19 transfected cells compared with those in si-NC transfected cells ( P<0.05). si-H19transfected cells had decreased expression of CyclinD1 and CDK4 ( P<0.05). ConclusionH19expression in colorectal cancer is high. Knock-down H19 expression can inhibit proliferation of colorectal cancer cells, which provides a potential strategy for targeted therapy of colorectal cancer.
斜卧青霉转录调控蛋白Hac1染色质免疫共沉淀分析方法的建立
Establishment of chromatin immunoprecipitation protocol for analysis of transcriptional regulation protein Hac1 in Penicillium decumbens

房艳华,,,,
- , 2018,
Abstract: 【目的】对斜卧青霉转录调控因子Hac1进行染色质免疫共沉淀(CHIP)试验,为其调控机制及生物学功能研究奠定基础。【方法】以斜卧青霉为材料,DTT诱导转录调控因子Hac1表达,用交联Buffer处理菌丝,使Hac1与靶基因交联,超声破碎染色质后,进行解交联染色体检验,研究不同交联时间(5,10,20,30,40 min)、不同菌丝用量(10 mL CHIP缓冲液中分别添加0.25,0.50,1.00,1.50 g菌丝)及不同超声功率(15,20,25,30 W)、超声时间(1,3,5 s)、超声间隔时间(10,20,30,40 s)、超声次数(15,25,30,40次)对试验效果的影响。在优化的条件下对菌丝进行处理,获得合格的DNA片段,进行CHIP试验,采用随机PCR方法检测染色质免疫共沉淀效果。【结果】适用于斜卧青霉Hac1的最佳染色质免疫共沉淀试验的条件为:交联时间控制在20 min以内;最佳菌丝用量为10 mL CHIP缓冲液中加入1 g菌丝;25 W超声功率,工作时间5 s,间隔时间40 s,超声30次。在优化的条件下富集DNA片段,进行随机PCR,结果在500~750 bp间可见明显的扩增条带。【结论】优化了斜卧青霉转录调控因子Hac1 CHIP条件,成功进行了CHIP试验。
【Objective】The objective of this study was to establish chromatin immunoprecipitation protocol for analysis of transcriptional regulation factor Hac1 in Penicillium decumbens,which would lay foundation for further study on the regulation mechanism and biological function of Hac1.【Method】In this study,DTT was used to induce the expression of Hac1.Mycelium were treated by crosslinking buffer and ultra-sonication was used for disruption of chromatin. The effects of crosslinking time (5,10,20,30,and 40 min),hyphae dosage added to 10 mL CHIP buffer (0.25,0.50,1.00,and 1.50 g),ultra-sonication power (15,20,25,and 30 W),working time (1,3,and 5 s),interval time (10,20,30,and 40 s)and working times (15,25,30,and 40) on CHIP were determined.Mycelium were then treated under the optimal conditions and the DNA collected by chromatin immunoprecipitation was determined by random PCR.【Result】The obtained optimal conditions of ultra-sonication were crosslinking time within 20 min,dosage for hyphae added to 10 mL CHIP buffer 1 g,power 25 W,working time 5 s,interval time 40 s and working for 30 times.According to these conditions,DNA fragments (500-750 bp) collected from chromatin immunoprecipitation were successfully detected by random PCR.【Conclusion】The chromatin immunoprecipitation protocol for analysis of Hac1 in Penicillium decumbens was successfully established
海南不同林龄木麻黄海防林土壤微生物群落组成与酶活性的动态分析
Analysis of soil microbial community and enzyme activity of Casuarina equisetifolia plantations at different stand ages in Hainan

徐志霞,,蔡莲子,
- , 2018,
Abstract: 【目的】研究海南滨海木麻黄林地土壤微生物群落组成和酶活性随林龄的变化规律,探讨木麻黄成熟林林地地力衰退的原因。【方法】在位于海南省海口市海滨的木麻黄幼龄林(5年生)、中龄林(15年生)和成熟林(30年生)中各设置3个10 m×10 m的样方,采用“S”形5点混合取样法取5~20 cm土层土样,提取土壤宏基因组DNA对土壤细菌、真菌的菌属组成、相对丰度和多样性进行分析,测定土壤酶活性并对酶活性与土壤理化性质的关系进行通径分析,同时对土壤微生物与土壤酶活性和理化性质的关系进行典范对应分析(CCA)。【结果】(1)中龄林土壤细菌和真菌群落的物种组成最丰富且均匀程度高。各林龄林地土壤细菌均以酸杆菌_Gp1占优势,中龄林土壤中特有菌属鞘氨醇杆菌属也为优势菌属。各林龄土壤真菌以发菌科中一种尚未分类的菌属占优势,其在成熟林中相对丰度最高。(2)随林龄增加,土壤蔗糖酶和脲酶活性逐渐升高,而过氧化氢酶、过氧化物酶活性逐渐降低,多酚氧化酶和酸性磷酸酶活性呈先降低后升高的趋势。通径分析表明,土壤呼吸作用、pH值及全钾、全磷、有机质含量是影响土壤酶活性的直接因素。(3)CCA分析表明,铵态氮对细菌群落的影响程度最大,而土壤体积质量对真菌群落的影响程度最大。多酚氧化酶活性与分枝杆菌属相关性最大,而酸性磷酸酶、过氧化物酶、过氧化氢酶活性与土壤真菌相关菌属相关性最大。土壤优势菌属中鞘氨醇杆菌属与有机质、硝态氮含量最相关,发菌科中一种尚未分类的真菌与过氧化氢酶活性、pH最相关。【结论】成熟林中微生物群落丰富度和均匀程度降低以及氧化还原酶类活性随林龄增长而逐渐降低,是木麻黄成熟林林地地力衰退的一个重要原因。
【Objective】This paper studied soil microbial community composition and soil enzyme activity of Casurina equisetifolia at different stages to explore the cause of soil degradation in C.equisetifolia mature plantation.【Method】C.equisetifolia plantations in the coast of Haikou,Hainan were selected and three 10 m×10 m sample plots were created in the stands at young stage (5-year),middle aged stage (15-year) and mature stage (30-year).The S shape five point sampling method was used for stratification and sampling of soil (5-20 cm).Metagenomic DNA was extracted for analyzing composition at genus level,relative abundance and diversity of the bacteria and fungi communities.The soil enzyme activities were also measured.Path analysis between soil enzyme activities and nutrients,as well as canonical correspondence analysis (CCA) of soil microbe,enzyme activities and soil physico chemical properties were carried out.【Result】(1) Richness and evenness of microbial communities were the highest in middle-aged forest.The population density of Acidobacteria_Gp1 was the greatest in the bacterial community at all ages.In the middle-aged forest,Sphingobacterium took advantage in the bacterial community.An unclassified Trichocomaceae was predominant in the fungal community,and its abundance was the highest in the mature forest.(2) The activities of urease and invertase increased as the growth of plantation,while the activities of catalase and peroxidase decreased.The polyphenol oxidase and acid phosphatase activities decreased from young stage to middle-aged stage,and then increased.Soil respiration,pH,total K,organic matter,and total P were crucial factors affecting enzyme activities.(3) Ammonia N was the largest factor on the bacterial community CCA ordination,and the soil bulk density impacted fungal community the most.Polyphenol oxidase activity showed good correlation to
藏药瑞香狼毒多糖提取工艺的优化及其抑菌和抗氧化活性研究
Optimization of polysaccharides extraction from Tibetan medicine Stellera chamaejasme and the antibacterial and antioxidant activities

,,,振亮,
- , 2018,
Abstract: 【目的】优化乙醇/(NH4)2SO4双水相体系提取藏药瑞香狼毒多糖的工艺参数,并分析瑞香狼毒多糖的抑菌及抗氧化活性,为瑞香狼毒功能产品的研发及多元化应用提供理论依据。【方法】以不同的料(g)液(mL)比(1∶30,1∶40,1∶50)、提取温度(45,55,65 ℃)和提取时间(20,30,40 min)作为考察因素,以多糖的提取率作为评价指标,采用响应曲面优化分析确定瑞香狼毒多糖最佳提取工艺参数。利用硫酸亚铁 水杨酸氧化法和邻苯三酚自氧化法分别评估瑞香狼毒多糖(质量浓度分别为0.6,1.2,1.8,2.4,3.0,3.6 mg/mL)对羟基自由基(·OH)和过氧负离子自由基(·O2-2)的体外清除能力。采用滤纸片扩散法研究瑞香狼毒多糖(质量浓度为0.3和3.0 mg/mL)的抑菌活性。【结果】料(g)液(mL)比1∶40、提取温度55 ℃、提取时间30 min为最优的工艺参数,在该条件下瑞香狼毒多糖的提取率最高,达15.34%。3.0 mg/mL瑞香狼毒多糖对·OH的清除率最大,为29.4%;2.4 mg/mL瑞香狼毒多糖对·O2-2的清除率最大,为24.7%。抑菌试验结果表明,3.0 mg/mL瑞香狼毒多糖对金黄色葡萄球菌和大肠杆菌高度敏感,对枯草芽孢杆菌中度敏感。【结论】确定了瑞香狼毒多糖乙醇/(NH4)2SO4双水相体系提取的最佳工艺参数,建立了因素与提取率之间的二次函数模型;瑞香狼毒多糖具有一定的体外抑菌、抗氧化活性。
【Objective】In this work, the extraction parameters of Stellera chamaejasme polysaccharides (SCP) using the aqueous two phase system of ethanol/ammonium sulphate were optimized and the antibacterial and antioxidant activities of SCP were evaluated to provide theoretical basis for research,development and diversification of the products.【Method】The optimal extraction parameters were determined using response surface method for extraction temperature (45,55 and 65 ℃),extraction time (20,30 and 40 min) and ratio of liquid to materials(1∶30,1∶40 and 1∶50) with SCP yield as index.The scavenging effect of hydroxyl radical and superoxide radical were detected with the oxidation of ferrous sulfate-salicylic acid and self oxidation of pyrogallic acid system under the mass concentrations of 0.6,1.2,1.8,2.4,3.0 and 3.6 mg/mL.The antibacterial activities at mass concentrations of 0.3 and 3.0 mg/mL were determined by filter paper diffusion method.【Result】The optimum extraction conditions were extraction temperature 55 ℃,extraction time 30 min and ratio of liquid to materials 1∶40 (g∶mL) with the highest SCP yield of 15.34%.SCP exhibited significant protection against hydroxyl radical and superoxide ion induced oxidative damage and the maximum scavenging activities were 29.4% (3.0 mg/mL) and 24.7%(2.4 mg/mL),respectively.The 3.0 mg/mL SCP presented high sensitivity to Colibacillus and Staphylococcus aureus,but medium sensitivity to Bacillus subtilis. 【Conclusion】 The optimum SCP extraction parameters by the aqueous two phase system of ethanol/ammonium sulphate were determined and a quadratic multinomial regression model between extraction factors and yield was established.SCP showed antioxidant and antimicrobial activities in vitro.
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