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1.
利用动物实验探讨低温刺激与大气PM2.5对大鼠肺组织及系统炎症因子的影响。方法将36只健康雄性Wistar大鼠按体重配对分成6组,随机给予0℃、10℃及20℃(常温对照)的单独低温刺激及低温+PM2.5暴露。给予低温+PM2.5暴露组低温刺激及气管滴注PM2.5[0.25 m L/8 mg·(只·次-1)],单独低温刺激组给予无菌生理盐[0.25 m L/(只·次-1)],间隔48h,连续3次。末次染毒48 h后处死大鼠,采用试剂盒法测定肺组织白介素-6(interleukin-6,IL-6)及C-反应蛋白(C-reactive protein,CRP)及血浆IL-6、CRP、白介素-8(interleukin-8,IL-8)及肿瘤坏死因子α(tumor necrosis factorα,TNF-α)水平。结果在不同低温刺激下,PM2.5染毒组肺组织中IL-6、CRP及血浆中IL-6、CRP及IL-8均显著高于单独低温刺激组(P0.05)。尤其在0℃时这种影响最为显著,肺和血液中的IL-6和CRP水平在该低温刺激下的PM2.5暴露组显著高于其他各组(P0.05)。两因素方差分析提示低温刺激与PM2.5对肺组织IL-6存在交互作用(P0.05),而对其他指标并未有显著的交互作用。肺组织中IL-6和CRP水平与血浆中的IL-6和CRP水平存在显著相关性(P0.05)。说明低温刺激可能增加大气PM2.5对大鼠肺组织及系统炎症的影响。  相似文献   

2.
目的 初步探讨 Protectin DX (保护素 DX,PDX)对老年大鼠肺叶切除术后肺损伤相关炎性介质及氧化因子 的调控及保护作用。 方法 将 30 只 SPF 级健康的老年雄性 SD 大鼠(10 月龄)随机分为假手术组( n = 10) 、手术组 ( n = 10) 、PDX 处理组( n = 10) 。 假手术组和手术组在造模 1 h 后腹腔注射 300 μL 生理盐水,PDX 处理组于造模 1 h 后腹腔注射 300 μL PDX(500 ng) 。 将所有大鼠于造模 24 h 后采用过度麻醉的方法处死,收集标本。 采用 HE 染色观察各组肺标本病理形态变化,评价各组大鼠肺标本的干湿质量比( W / D) ;检测肺泡灌洗液中蛋白浓度及相 关炎症因子的含量;检测肺组织中 MDA、ROS、SOD 的含量以及 HO-1、核因子 NF-κB 的蛋白表达量。 结果 假手术 组肺组织结构清晰,未见炎症细胞浸润;手术组老年大鼠肺组织结构紊乱,伴有大量炎症细胞浸润;PDX 处理组大 鼠肺组织结构不清晰,存在少量的炎症细胞浸润。 与假手术组相比较,手术组老年大鼠肺损伤评分及肺组织 W / D 显著增高( P<0. 01) ,肺泡灌洗液中蛋白浓度及 IL-1β、IL-6 和 TNF-α 含量明显增加( P< 0. 01) ,肺组织中 MDA、ROS 含量及 NF-κB 蛋白表达显著升高,SOD 活性及 HO-1 蛋白表达明显降低( P< 0. 05) 。 与手术组相比较,PDX 处理组 老年大鼠肺损伤评分及肺组织 W / D 显著降低( P<0. 01) ,肺泡灌洗液中蛋白浓度及 IL-1β、IL-6 和 TNF-α 含量明显 下降( P<0. 01) ,肺组织中 MDA、ROS 含量及 NF-κB 蛋白表达显著降低,SOD 活性及 HO-1 蛋白表达明显升高( P < 0. 05) 。 结论 PDX 能够明显减低老年大鼠肺叶切除术后的肺损伤程度,这种作用可能与其调节肺组织中 HO-1、 NF-κB 蛋白的表达从而抑制肺部的氧化应激反应和炎症反应相关。  相似文献   

3.
流行病学证据表明,老年人长期接触PM2.5可能导致记忆障碍.为了探究短期、严重雾霾天气对人们健康的影响,以C57BL/6J小鼠为研究对象,用不同浓度的PM2.5(0、193、1 930、19 300 μg·kg-1·day-1),通过鼻腔滴注的实验,染毒1 w,探究急性高浓度PM2.5污染所造成的神经毒性.首先通过Morris水迷宫实验对小鼠认知能力进行检测,暴露结束后对小鼠脑组织进行组织病理学检测(H&E)、氧化应激水平测定(ROS、MDA、SOD).实验结果表明,急性高浓度PM2.5暴露虽然不影响小鼠大脑的生长发育,但会导致小鼠认知能力下降,高剂量19 300 μg·kg-1·day-1PM2.5染毒组小鼠与空白对照组小鼠5 d逃避潜伏期的平均值有显著性差异(为P<0.05);小鼠脑组织海马区出现病理学损伤;小鼠脑组织中的ROS水平、MDA含量上升,SOD活性下降.实验揭示了急性高浓度PM2.5暴露对小鼠脑组织能造成氧化损伤,破坏海马神经中枢细胞结构,影响小鼠的学习记忆能力.  相似文献   

4.
研究采集PM_(2.5)样本,制备PM_(2.5)生理盐水混悬液,对雄性SD大鼠进行染毒实验,检测大鼠肺组织病理学改变,测定肺中炎症因子和CK-18mRNA和蛋白表达。结果显示,随着PM_(2.5)染毒剂量增加,肺组织出现肺充血和炎性细胞浸润等炎症反应,冬季PM_(2.5)所致肺病理学损伤比夏季严重。冬季PM_(2.5)中、高剂量组和夏季高剂量组大鼠肺中TNF-α、IL-6、TGF-β、CK-18mRNA和蛋白表达比对照组显著增加。这说明PM_(2.5)亚慢性染毒可增加炎症因子表达水平,促进肺炎症反应。CK-18表达上调提示PM_(2.5)致肺组织处于氧化应激状态。太原市冬季PM_(2.5)引起大鼠肺炎症损伤效应比夏季严重。  相似文献   

5.
At 1.0?4.0 GPa and 1123?1473 K and under oxygen fugacity-controlled conditions (Ni+NiO, Fe+Fe3O4, Fe+FeO and Mo+MoO2 buffers), a YJ-3000t Model six-anvil solid high-pressure apparatus and a Sarltron-1260 Impedance/Gain-Phase analyzer were employed to conduct an in situ measurement of the electrical conductivity of single crystal olivine. Experimental results showed that: (1) within the range of experimentally selected frequencies (103?106 Hz), the electrical conductivity of the sample is of great dependence on the frequency; (2) with the rise of temperature (T), the electrical conductivity (σ) will increase, and the Arrenhius linear relationship is established between lgσ and 1/T; (3) under the control of oxygen buffer Fe+Fe3O4, with the rise of pressure, the electrical conductivity tends to decrease whereas the activation enthalpy and independent-of-temperature preexponential factor tend to increase, with the activation energy and activation volume of the sample estimated at (1.25±0.08) eV and (0.105±0.025) cm3/mol, respectively; (4) under given pressure and temperature conditions, the electrical conductivity tends to increase whereas the activation energy tends to decrease with increasing oxygen fugacity; and (5) the mechanism of electrical conduction of small polarons can provide insight into the behavior of electrical conduction of olivine under high pressure and high temperature.  相似文献   

6.
为观察五味沙棘口服液对实验性慢性支气管炎动物模型的防治作用,初步探讨其作用机制,采用改良烟熏法复制大鼠慢性支气管炎模型,分为7组,按设计剂量分别灌胃给药,连续21d,末次给药后第2d取样,测定各组大鼠血清、肺组织及支气管肺泡灌洗液(BALF)中内皮素(ET-1)、一氧化氮(NO)肿瘤坏死因子(TNF-α)、白细胞介素(IL-8)、丙二醛(MDA)的含量.取部分肺组织进行病理学观察.结果显示模型组大鼠血清、肺组织及BALF中TNF-α、IL-8、ET-1、MDA含量均较正常组明显升高(P0.01),NO含量则明显低于正常对照组(P0.01).治疗组(除五味沙棘口服液低剂量组)大鼠血清、肺组织及BALF中TNF-α、IL-8、ET-1、MDA含量较模型组明显降低(P0.01或P0.05),NO含量则明显高于模型组(P0.01或P0.05),改善肺组织病理损伤.藏药五味沙棘口服液在一定程度上可治疗慢性支气管炎,且对肺组织具有一定的保护性.其作用机制可能与它增强肺组织自由基清除能力、改善机体功能状态、抑制炎性细胞因子的释放有关.  相似文献   

7.
采用亚铁(Fe2+)分别联合次氯酸钠(NaClO)、过硫酸钠(Na?S?O8)和过氧化氢(H2O2) 3种氧化剂处理某原油浸染土壤的热脱附废水,考察了pH值、Fe2+投加量、氧化剂投加量和反应时间对处理效能的影响。Fe2+/H2O2和Fe2+/ Na?S?O8均能有效去除热脱附废水中的典型污染物——石油烃物质,去除率分别达到100.0%和97.8%,但Fe2+/H2O2体系对化学耗氧量(COD)的去除效果明显优于Fe2+/Na?S?O8。Fe2+/H2O2可将有机物彻底氧化分解,而Fe2+/NaClO和Fe2+/Na?S?O8仅是将有机物氧化分解为中间物质。多元变量分析结果表明,pH值和氧化剂投加量是影响去除效果的主要因素,Fe2+/H2O2处理热脱附废水的吨水处理成本较高,但是综合效果最好;Fe2+/Na?S?O8处理成本次之,但无法彻底降解COD;Fe2+/NaClO成本最低,但对有机物去除效果最差。综合去除效果和经济因素考量, Fe2+/H2O2体系更适用于处理热脱附废水。  相似文献   

8.
 用失重法研究了4种金属离子(Na+,Zn2+,Cu2+,Fe3+)在0.5 mol/L H2SO4以及500 mg/L没食子酸+0.5 mol/L H2SO4介质中在20℃对冷轧钢腐蚀行为的影响.结果表明:Cu2+对钢的腐蚀起抑制作用;而其余3种金属离子(Na+,Zn2+,Fe3+)对钢的腐蚀起加速作用.在相同条件下,冷轧钢在0.5 mol/L H2SO4溶液中的腐蚀速率顺序为:Cu2+2++3+;而在500 mg/L没食子酸+0.5 mol/L H2SO4介质中,腐蚀速率顺序为:Cu2+2+3++.  相似文献   

9.
以2017年PM2.5污染较为严重的贵州六盘水市为研究对象,分析PM2.5的月变化与季变变,探讨PM2.5污染来源与各个因子之间的关系。通过PM2.5与平均气温的相关性分析、PM2.5与平均植被指数的相关性分析,以月、季为时间尺度对六盘水市5的监测点(PM2.5)进行浓度变化分析。得出时间上六盘水市大气中PM2.5浓度变化具有季节性,季平均气温与季平均PM2.5呈负相关,各监测点(PM2.5)在冬季最高,各监测点平均PM2.5浓度达到55.16μg/m3,夏季最低为22.59μg/m3。季PM2.5浓度变化与季平均植被指数呈现负相关,植被覆盖的变化对大气PM2.5浓度变化有显著影响,在土地利用类型中耕地与领地的植被指数变化最大,土地利用类型当中的耕地与林地对大气中PM2.5浓度变化有显著影响。  相似文献   

10.
佤药灯台树对大鼠博莱霉素所致肺损伤早期作用的研究   总被引:1,自引:0,他引:1  
观察佤药灯台树对博莱霉素诱导的大鼠肺泡炎早期的防治作用。以博莱霉素气管内注射建立肺纤维化模型,第二天分别给与灯台树和强的松灌胃治疗,于给药第7d、14d处死动物,右肺组织行病理组织学检查,左肺组织匀浆进行超氧化物歧化酶(SOD)活力、丙二醛(MDA)、谷胱甘肽(GSH)、肿瘤坏死因子(TNf-α)含量检测。结果与博莱霉素对照组相比:各治疗组肺泡炎的程度均明显减轻;7d时灯台树组肺组织匀浆MDA、TNF-α含量降低(P<0.05),强的松组肺组织匀浆GSH含量升高(P<0.05);14d时灯台树、强的松组肺组织匀浆SOD活力、GSH含量均增高(P<0.05),MDA含量降低(P<0.05)。证明灯台树水煎液可以增强SOD的活性,提高清除氧自由基能力,减轻脂质过氧化物损伤,维持氧化/抗氧化平衡。对肺损伤后早期肺泡炎阶段具有显著治疗作用。  相似文献   

11.
A murine CD4+ thymocyte subset with phenotype of TCRαβ+ 3G11 6C10 CD4+ CD8 CD69+/- HSAmed/lo contains the cells in relatively functional matured status. The functional property of the cells in this subset is characterized by the unique pattern of cytokine production at transitional stage from Th0 to Th2 type with the latter being the dominant type. After being co-cultured with murine thymic medullary epithelial cell line (MTEC1) cells, a murine thymic medullary type epithelial cell line, the TCRαβ+ 3G11 6C10 CD4+ CD8 CD69+/- HSAmed/lo thymocytes, has exhibited significantly higher levels of proliferation capability and IL-6 production, whereas the production of IL-4 and IL-10 is suppressed after co-culturing with MTECl. By contrast, MTECl could not induce thymocytes to secrete Thl type of cytokines. The results suggest that MTECl can regulate functional status of this thymocyte subset and induce them to develop into a specialized Th2 subset.  相似文献   

12.
给出了Na+-K+-ATP酶跨越细胞膜同时主动向胞内运转钾离子和向胞外运转钠离子这一生化过程的π-演算模型及该模型的Spin验证. 证明了用过程代数的方法表示以“相互通讯”和“可移动”为主要特征的生物系统并模拟其行为的可行性.   相似文献   

13.
Effects of La3+ and Gd3+ on Ca2+ influx were investigated in rat hepatoma H-35 cells by measuring the initial rate of45Ca2+ uptake. It was found that the maximum initial rate of Ca2+ uptake was increased six-to ten-fold at low concentrations of La3+ and Gd3+. Kinetic analyses by measuring the initial rate of Ca2+ influx at different external Ca2+ concentrations indicated the existence of two intracellular exchangeable components in the basal Ca2+ system, with low and high affinities for Ca2+, and only one class of Ca2+ binding sites was observed in the La3+-or Gd3+-treated cells. For high affinity, La3+ and Gd3+ increased both kinetic parametersK m andV max of basai Ca2+ influx. La3+ and Gd3+ compete directly with Ca2+ for Ca2+ binding site for low affinity. The kinetics is competitive.  相似文献   

14.
TCRαβCD4-CD8+ thymocytes are heterogeneity. They may undergo phenotypic and functional maturation within thymic medulla. Medullary-type CD8SP thymocytes were divided into seven subsets based on phenotypic analysis, and their precursor-progeny relationship along with the differential pathway was also delineated. To further testify the validity of the maturation pathway, we purified 6C10-CD69+ cells representing the early stage and 6C10-Qa-2+ cells representing the later stage among medullary-type CD8SP thymocytes and compared their functional maturation levels. CD8+ T cells of spleen were used as the control. It is shown that there is no obvious difference of proliferation ability among these three subsets; however, intracytoplasmic cytokine assay shows that there is a hier archy of IFN-γ and TNFα secretion among these subsets, strikingly comparable to their phenotypic status among medullary type CD8SP thymocytes. The bioassays of IL-2 and IFN-γ in culture supernatant give the similar results.  相似文献   

15.
Activities of234Th and nutrient concentrations in the upper 500 m water column were measured at a time-series station in the South China Sea over a time span of 12.3 d. Results showed a reduction of dissolved234Th and an overall increase of particulate234Th during the period. Meanwhile, activities of total234Th kept fairly constant, implying rapid transformation of234Th between the dissolved and particulate forms. Vertical profiles of total234Th showed evident deficit of234Th relative to238U in the upper 500 m water column. Using an irreversible steady-state model of thorium scavenging, export fluxes of particulate organic carbon (POC) corresponding to time pointsT 1 andT 2 were estimated to be 46.5 and 13.1 mmolC · m−2 · d−1. It was demonstrated that the estimation of POC export was greatly dependent on the POC/234ThP ratios and the bias caused by the different models of234Th scavenging, however, was considered to be of minor importance.  相似文献   

16.
The oxygen isotopic data for amphibolites from Archaean continental nucleus, North China Craton indicate that ( i ) the evolving lines structured by the data are parallel to the geoselenic evolving line, which means that the parent materials of these continental nucleus originated from solar matter; ( ii ) different intercepts for these evolving lines manifest that oxygen isotopic compositions of different continental nucleus are heterogeneous, which means that these continental nucleuses originated from different parent resources with different original compositions.  相似文献   

17.
A new method suitable for determining specific activity of230Th in uranium ore samples is built. The method is characterized by adding the230Th/232Th standard dilution agent with lower activity ratio (Its230Th/232Th activity ratio and230Th have been known) to the samples and using isotopic dilution analysis. The method can be applied to analyses of230Th specific activity in various230Th/232Th activity ratio samples. The precision can also be improved.  相似文献   

18.
采用溶剂热法在N,N-二甲基甲酰胺溶液中合成了不同摩尔比例的SrCl_2和Bi(NO_3)_3(分别为5%,10%,30%,50%,80%)与对苯二甲酸形成的含Sr~(2+)和Bi~(3+)有机杂化体,并在紫外可见光照射下对其进行了罗丹明B降解活性的评价.结果表明:杂化体在紫外可见光下对RhB降解活性良好,其中SrCl_2摩尔比例10%掺杂的催化剂光降解活性最佳,这归结于其在紫外区域对光有很好的吸收及光生电子和空穴能有效地分离.双金属离子能协同调节有机杂化体的光催化活性.  相似文献   

19.
Phenotypic analysis of the medullary-type CD4 CD8+ (CD8SP) thymocytes has revealed phenotypic heterogeneity within this cell population. The phenotype of mature peripheral CDS+T cells is TCRαβ+CD3+Qa-2+HSA 3G116C10, whereas in the medullary-type CD8SP thymocytes, 20% are Qa-2+; 33%, HAS; 30%, 3G11; and 70% are 6C10. The disparate expression patterns of these four cell surface markers suggest that medullary-type CD8SP thymocytes may undergo phenotypic maturation process. According to the distribution of these four cell surface markers, six subgroups of CD8SP thymocytes have been identified. The precursor-progeny relationship along with developmental pathway is postulated as follows: 6C10+HSA+3G11 Qa-2→ 6C10+HSA+ 3G11+Qa-2 → 6C10 HSA+3G11+Qa-2 → 6C10HSA3G11+Qa-2 → 6C10HSA3G11 Qa-2 → 6C10HA S 3G11 Qa-2+, the cells in the last subgroup exit the thymus and home into periphery.  相似文献   

20.
The samples of Caledonian mylonitized granite and Jurassic meta-sedimentary rocks were collected in the north of Dangjinshan Pass, Qaidam gate fault-valley and Gesi fault-valley. Detailed studies under the microscope and electronic microscope suggest that all the samples contain the syntectonic-growing minerals such as white mica, chlorite, sericite, biotite, etc. By dating these minerals, we got a group of 40Ar/39Ar laser probe isochronal ages of 89—92 Ma and apparent ages of (46.6±6.4) Ma. The ages ranging from 97 to 46 Ma were reported for the first time in the isotopic dating researches of the Altyn Fault. The isochronal age group of (98—89) Ma indicates that a ductile strike-slip event, with low-grade metamorphism, began in late Cretaceous. This suggests that the strike-slip movement of the Altyn Fault should be related to the formation of the so-called west tectonic syntaxis in the Nepal-western Kunlun area.  相似文献   

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