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Sensitivity of Total-Dose Radiation Hardness of SIMOX Buried Oxides to Doses of Nitrogen Implantation into Buried Oxides 被引量:2
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作者 郑中山 刘忠立 +6 位作者 张国强 李宁 李国花 马红芝 张恩霞 张正选 王曦 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第5期862-866,共5页
In order to improve the total-dose radiation har dness of the buried oxides(BOX) in the structure of separation-by-implanted-oxygen(SIMOX) silicon-on-insulator(SOI),nitrogen ions are implanted into the buried oxides w... In order to improve the total-dose radiation har dness of the buried oxides(BOX) in the structure of separation-by-implanted-oxygen(SIMOX) silicon-on-insulator(SOI),nitrogen ions are implanted into the buried oxides with two different doses,2×10 15 and 3×10 15 cm -2 ,respectively.The experimental results show that the radiation hardness of the buried oxides is very sensitive to the doses of nitrogen implantation for a lower dose of irradiation with a Co-60 source.Despite the small difference between the doses of nitrogen implantation,the nitrogen-implanted 2×10 15 cm -2 BOX has a much higher hardness than the control sample (i.e.the buried oxide without receiving nitrogen implantation) for a total-dose irradiation of 5×104rad(Si),whereas the nitrogen-implanted 3×10 15 cm -2 BOX has a lower hardness than uhe control sample.However,this sensitivity of radiation hardness to the doses of nitrogen implantation reduces with the increasing total-dose of irradiation (from 5×104 to 5×105rad (Si)).The radiation hardness of BOX is characterized by MOS high-frequency (HF) capacitance-voltage (C-V) technique after the top silicon layers are removed.In addition,the abnormal HF C-V curve of the metal-silicon-BOX-silicon(MSOS) structure is observed and explained. 展开更多
关键词 SIMOX buried oxide radiation-hardness nitrogen implantation
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A novel high performance TFS SJ IGBT with a buried oxide layer 被引量:2
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作者 张金平 李泽宏 +1 位作者 张波 李肇基 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第8期625-630,共6页
A novel high performance trench field stop (TFS) superjunction (S J) insulated gate bipolar transistor (IGBT) with a buried oxide (BO) layer is proposed in this paper. The BO layer inserted between the P-base ... A novel high performance trench field stop (TFS) superjunction (S J) insulated gate bipolar transistor (IGBT) with a buried oxide (BO) layer is proposed in this paper. The BO layer inserted between the P-base and the SJ drift region acts as a barrier layer for the hole-carrier in the drift region. Therefore, conduction modulation in the emitter side of the SJ drift region is enhanced significantly and the carrier distribution in the drift region is optimized for the proposed structure. As a result, compared with the conventional TFS SJ IGBT (Conv-SJ), the proposed BO-SJ IGBT structure possesses a drastically reduced on-state voltage drop (gce(on)) and an improved tradeoff between gee(on) and turn-off loss (Eoff), with no breakdown voltage (BV) degraded. The results show that with the spacing between the gate and the BO layer Wo = 0.2 μm, the thickness of the BO layer Lo = 0.2 μm, the thickness of the drift region Ld = 90 μm, the half width and doping concentration of the N- and P-pillars Wn = Wp = 2.5μm and Nn = Np = 3 × 10^15 cm^-3, the Vce(on) and Eoff of the proposed structure are 1.08 V and 2.81 mJ/cm2 with the collector doping concentration Nc = 1 × 10^18 cm^-3 and 1.12 V and 1.73 mJ/cm2 with Nc = 5 × 10^17 cm^-3, respectively. However, with the same device parameters, the Vce(on) and Eoff for the Conv-SJ are 1.81 V and 2.88 mJ/cm2 with Nc= 1 × 10^18 cm^-3 and 1.98 V and 2.82 mJ/cm2 with Nc = 5 ×10^17 cm^-3, respectively. Meanwhile, the BV of the proposed structure and Conv-SJ are 1414 V and 1413 V, respectively. 展开更多
关键词 insulated gate bipolar transistor trench field stop SUPERJUNCTION buried oxide layer
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Compound buried layer SOI high voltage device with a step buried oxide
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作者 王元刚 罗小蓉 +7 位作者 葛锐 吴丽娟 陈曦 姚国亮 雷天飞 王琦 范杰 胡夏融 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第7期399-404,共6页
A silicon-on-insulator (SOI) high performance lateral double-diffusion metal oxide semiconductor (LDMOS) on a compound buried layer (CBL) with a step buried oxide (SBO CBL SOI) is proposed. The step buried oxi... A silicon-on-insulator (SOI) high performance lateral double-diffusion metal oxide semiconductor (LDMOS) on a compound buried layer (CBL) with a step buried oxide (SBO CBL SOI) is proposed. The step buried oxide locates holes in the top interface of the upper buried oxide (UBO) layer. Furthermore, holes with high density are collected in the interface between the polysilicon layer and the lower buried oxide (LBO) layer. Consequently, the electric fields in both the thin LBO and the thick UBO are enhanced by these holes, leading to an improved breakdown voltage. The breakdown voltage of the SBO CBL SOI LDMOS increases to 847 V from the 477 V of a conventional SOI with the same thicknesses of SOI layer and the buried oxide layer. Moreover, SBO CBL SOI can also reduce the self-heating effect. 展开更多
关键词 breakdown voltage step buried oxide compound buried layer self-heating effect
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Oxidative desulfurization of model and real oil samples using Mo supported on hierarchical alumina–silica: Process optimization by Box–Behnken experimental design 被引量:1
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作者 Nasim Ghorbani Gholamreza Moradi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第11期2759-2770,共12页
The catalytic performance of Mo supported on hierarchical alumina–silica(Si/Al = 15) with Mo loadings of 3, 6 and 15 wt% was investigated for the oxidative desulfurization(ODS) of model and real oil samples. Hierarch... The catalytic performance of Mo supported on hierarchical alumina–silica(Si/Al = 15) with Mo loadings of 3, 6 and 15 wt% was investigated for the oxidative desulfurization(ODS) of model and real oil samples. Hierarchical alumina–silica(h Al–Si) was synthesized by economical and ecofriendly silicate-1 seed-induced route using cetyltrimethylammonium bromide(CTAB) as mesoporogen. The effect of CTAB on the structure of catalyst was studied by characterization techniques. The results revealed that 6%Mo/h Al–Si had the highest sulfur removal compared to the other catalyst loadings. The effect of operating parameters was evaluated using Box–Behnken experimental design. The optimal desulfurization conditions with the 6%Mo/h Al–Si catalyst were determined at oxidation temperature of 67 ℃, oxidation time of 42 min, H2O2/S molar ratio of 8 and catalyst dosage of 0.008 g·ml^-1 for achieving a conversion of 95%. Under optimal conditions, different sulfur-containing compounds with initial concentration of 1000 ppm, Dibenzothiophene(DBT), Benzothiophene(BT) and Thiophen(Th), showed the catalytic oxidation reactivity in the order of DBT > BT>Th. According to the regeneration experiments, the 6%Mo/h Al–Si catalyst was reused 4 times with a little reduction in the performance. Also, the total sulfur content of gasoline and diesel after ODS process reached 156.6 and 4592.2 ppm, respectively. 展开更多
关键词 oxidATIVE DESULFURIZATION HIERARCHICAL alumina–silica Silicate-1 seed-induced route box–Behnken experimental design
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Simulation and Experiment on a Buried-Oxide Trench-Gate Bipolar-Mode JFET
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作者 田波 吴郁 +2 位作者 胡冬青 韩峰 亢宝位 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第10期1860-1863,共4页
A buried-oxide trench-gate bipolar-mode JFET (BTB-JFET) with an oxide layer buried under the gate region to reduce the gate-drain capacitance Cgd is proposed. Simulations with a resistive load circuit for power loss... A buried-oxide trench-gate bipolar-mode JFET (BTB-JFET) with an oxide layer buried under the gate region to reduce the gate-drain capacitance Cgd is proposed. Simulations with a resistive load circuit for power loss comparison at high frequency application are performed with 20V-rated power switching devices,including a BTB-JFET,a trench MOSFET (T-MOSFET) generally applied in present industry, and a conventional trench-gate bipolar-mode JFET (TB-JFET) without buried oxide,for the first time. The simulation results indicate that the switching power loss of the normally-on BTB-JFET is improved by 37% and 14% at 1MHz compared to the T-MOSFET and the normally-on TB-JFET, respectively. In order to demonstrate the validity of the simulation, the normally-on TB-JFET and BTB-JFET have been fabricated successfully for the first time, where the buried oxide structure is realized by thermal oxidation. The experimental results show that the Cgd of the BTB-JFET is decreased by 45% from that of the TB-JFET at zero source-drain bias. Compared to the TB-JFET,the switching time and switching power loss of the BTB-JFET decrease approximately by 7. 4% and 11% at 1MHz,respectively. Therefore,the normally-on BTB-JFET could be pointing to a new direction for the R&D of low volt- age and high frequency switching devices. 展开更多
关键词 TB-JFET BTB-JFET buried oxide gate-drain capacitance switching power loss
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Box-Behnken效应面法优化Ni/ZnO-SiO_2复合氧化物制备工艺及其吸附脱硫性能研究 被引量:1
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作者 张玉婷 张景成 于海斌 《化学工程师》 CAS 2016年第3期77-79,共3页
利用响应曲面法对影响Ni/ZnO-SiO_2复合氧化物制备工艺的主要因素:活性金属组分比例、成胶pH值、老化时间进行试验设计。以Ni/ZnO-SiO_2复合氧化物用于低硫石脑油吸附脱硫处理中,产物硫含量为响应函数,建立相应的数学模型,优化试验方法... 利用响应曲面法对影响Ni/ZnO-SiO_2复合氧化物制备工艺的主要因素:活性金属组分比例、成胶pH值、老化时间进行试验设计。以Ni/ZnO-SiO_2复合氧化物用于低硫石脑油吸附脱硫处理中,产物硫含量为响应函数,建立相应的数学模型,优化试验方法。得到的最佳试验条件为:活性金属组分比例(Ni/Zn)为1.09、成胶pH值为5、老化时间为5h。此时Ni/ZnO-SiO_2复合氧化物对低硫石脑油的吸附脱硫性能为最优。Box-Behnke实验设计法用于Ni/ZnO-SiO_2复合氧化物制备工艺优化筛选是可行的,数学模型的预测值与实验观察值相符。 展开更多
关键词 响应曲面法 Ni/ZnO-SiO_2复合氧化物 box-Behnken实验设计 吸附脱硫
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宫颈癌DExH-box解旋酶9抑制转录本来源的长链非编码RNA在高糖诱导的心肌细胞氧化应激损伤过程中的作用及其机制
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作者 马健 杨维维 +2 位作者 李帅 袁敏杰 魏盟 《上海医学》 CAS 2021年第8期583-587,共5页
目的探讨宫颈癌DExH-box解旋酶9抑制转录本来源的长链非编码RNA(lnc-CCDST)对高糖诱导的新生小鼠心肌细胞(NMC)中活性氧(ROS)生成和细胞凋亡的影响,以及微RNA-339-5p(miR-339-5p)负向调节lnc-CCDST的机制。方法①构建小鼠1型糖尿病模型... 目的探讨宫颈癌DExH-box解旋酶9抑制转录本来源的长链非编码RNA(lnc-CCDST)对高糖诱导的新生小鼠心肌细胞(NMC)中活性氧(ROS)生成和细胞凋亡的影响,以及微RNA-339-5p(miR-339-5p)负向调节lnc-CCDST的机制。方法①构建小鼠1型糖尿病模型后,检测其心肌细胞lnc-CCDST表达,体外实验采用高浓度葡萄糖(35 mmol/L)培养基刺激NMC后测定细胞内lnc-CCDST表达;②小干扰RNA(siRNA)抑制NMC中lnc-CCDST表达再予高糖刺激24 h,测定细胞内ROS含量、胱天蛋白酶-3(caspase-3)活性,以及DNA片段(DNA fragmentation);③过表达和抑制miR-339-5p,验证其参与lnc-CCDST的调节;④过表达miR-339-5p后再予高糖刺激,检测细胞内ROS生成、caspase-3活性,以及DNA fragmentation;⑤过表达lnc-CCDST和(或)miR-339-5p,分析miR-339-5p对心肌细胞氧化应激损伤的保护作用。结果糖尿病小鼠心肌组织中和高糖诱导后的NMC中lnc-CCDST的表达分别较相应的对照组均显著增加(P值均<0.01);高糖诱导后NMC的ROS生成、caspase-3活性和DNA fragmentation均显著增加(P值均<0.05),而抑制lnc-CCDST表达可减少高糖诱导的ROS生成、caspase-3活性和DNA fragmentation增加(P值均<0.05)。在NMC中过表达miR-339-5p,可显著抑制lnc-CCDST表达;抑制miR-339-5p可促进lnc-CCDST表达(P值均<0.05)。此外,过表达miR-339-5p能够显著抑制高糖诱导的ROS生成、caspase-3活性和DNA fragmentation增加(P值均<0.05),而此作用可被过表达lnc-CCDST所抵消。结论lnc-CCDST参与高糖诱导的心肌细胞氧化应激损伤过程,而这一作用受miR-339-5p负向调节。 展开更多
关键词 宫颈癌DExH-box解旋酶9抑制转录本来源的长链非编码RNA 微RNA miR-339-5p 氧化应激损伤 细胞凋亡
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Abdominal paracentesis drainage ameliorates myocardial injury in severe experimental pancreatitis rats through suppressing oxidative stress 被引量:14
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作者 Yi Wen Hong-Yu Sun +5 位作者 Zhen Tan Ruo-Hong Liu Shang-Qing Huang Guang-Yu Chen Hao Qi Li-Jun Tang 《World Journal of Gastroenterology》 SCIE CAS 2020年第1期35-54,共20页
BACKGROUND Abdominal paracentesis drainage(APD)is a safe and effective strategy for severe acute pancreatitis(SAP)patients.However,the effects of APD treatment on SAPassociated cardiac injury remain unknown.AIM To inv... BACKGROUND Abdominal paracentesis drainage(APD)is a safe and effective strategy for severe acute pancreatitis(SAP)patients.However,the effects of APD treatment on SAPassociated cardiac injury remain unknown.AIM To investigate the protective effects of APD on SAP-associated cardiac injury and the underlying mechanisms.METHODS SAP was induced by 5%sodium taurocholate retrograde injection in Sprague-Dawley rats.APD was performed by inserting a drainage tube with a vacuum ball into the lower right abdomen of the rats immediately after SAP induction.Morphological staining,serum amylase and inflammatory mediators,serum and ascites high mobility group box(HMGB)1,cardiac-related enzymes indexes and cardiac function,oxidative stress markers and apoptosis and associated proteins were assessed in the myocardium in SAP rats.Nicotinamide adenine dinucleotide phosphate oxidase activity and mRNA and protein expression were also examined.RESULTS APD treatment improved cardiac morphological changes,inhibited cardiac dysfunction,decreased cardiac enzymes and reduced cardiomyocyte apoptosis,proapoptotic Bax and cleaved caspase-3 protein levels.APD significantly decreased serum levels of HMGB1,inhibited nicotinamide adenine dinucleotide phosphate oxidase expression and ultimately alleviated cardiac oxidative injury.Furthermore,the activation of cardiac nicotinamide adenine dinucleotide phosphate oxidase by pancreatitis-associated ascitic fluid intraperitoneal injection was effectively inhibited by adding anti-HMGB1 neutralizing antibody in rats with mild acute pancreatitis.CONCLUSION APD treatment could exert cardioprotective effects on SAP-associated cardiac injury through suppressing HMGB1-mediated oxidative stress,which may be a novel mechanism behind the effectiveness of APD on SAP. 展开更多
关键词 Abdominal paracentesis drainage Severe acute pancreatitis Myocardial injury High mobility group box 1 Nicotinamide adenine dinucleotide phosphate oxidase oxidative stress
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Influence of nitrogen dose on the charge density of nitrogen-implanted buried oxide in SOI wafers 被引量:1
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作者 郑中山 刘忠立 +2 位作者 李宁 李国花 张恩霞 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2010年第2期99-102,共4页
To harden silicon-on-insulator(SOI) wafers fabricated using separation by implanted oxygen(SIMOX) to total-dose irradiation,the technique of nitrogen implantation into the buried oxide(BOX) layer of SIMOX wafers... To harden silicon-on-insulator(SOI) wafers fabricated using separation by implanted oxygen(SIMOX) to total-dose irradiation,the technique of nitrogen implantation into the buried oxide(BOX) layer of SIMOX wafers can be used.However,in this work,it has been found that all the nitrogen-implanted BOX layers reveal greater initial positive charge densities,which increased with increasing nitrogen implantation dose.Also,the results indicate that excessively large nitrogen implantation dose reduced the radiation tolerance of BOX for its high initial positive charge density. The bigger initial positive charge densities can be ascribed to the accumulation of implanted nitrogen near the Si-BOX interface after annealing.On the other hand,in our work,it has also been observed that,unlike nitrogen-implanted BOX,all the fluorine-implanted BOX layers show a negative charge density.To obtain the initial charge densities of the BOX layers,the tested samples were fabricated with a metal-BOX-silicon(MBS) structure based on SIMOX wafers for high-frequency capacitance-voltage(C-V) analysis. 展开更多
关键词 buried oxide charge density nitrogen implantation fluorine implantation
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E-box元件对大鼠γ-GCS催化亚单位基因调控作用的组织特异性研究 被引量:4
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作者 陈辉 李冰 冉丕鑫 《广州医学院学报》 2007年第1期1-5,共5页
目的:探讨大鼠γ-谷氨酰半胱氨酸合成酶(γ-GCS)催化亚单位(GCLC)基因启动子(-745~-705)区段E-box元件对其转录调控是否存在组织细胞差异性。方法:分别将GCLC5’端上游序列驱动的荧光素酶报道基因载体GCLC-Luc、E-box缺失的delE-box-GC... 目的:探讨大鼠γ-谷氨酰半胱氨酸合成酶(γ-GCS)催化亚单位(GCLC)基因启动子(-745~-705)区段E-box元件对其转录调控是否存在组织细胞差异性。方法:分别将GCLC5’端上游序列驱动的荧光素酶报道基因载体GCLC-Luc、E-box缺失的delE-box-GCLC-Luc及pGL3-enhancer空载体瞬时转染大鼠不同组织来源的细胞,测得荧光素酶活性;并经蛋白定量及pSV-β-半乳糖苷酶的活性测定,获得校正荧光素酶活性值,通过比较校正荧光素酶活性值差异间接判断E-box元件对GCLC转录活性的影响。结果:在大鼠心肌细胞H9C2(2-1),转染delE-box-GCLC-Luc组荧光素酶活性值较转染GCLC-Luc组明显升高(P<0.001),说明E-box能使其GCLC转录活性下调;在大鼠肾小球细胞HBZY-1,转染delE-box-GCLC-Luc组荧光素酶活性值较GCLC-Luc组明显降低(P<0.02),提示E-box具有上调该细胞GCLC转录活性的作用;而在大鼠神经胶质瘤细胞C6和小肠隐窝上皮细胞IEC-6,组间差异无统计学意义(P>0.05),提示E-box对其GCLC转录活性无影响。结论:E-box元件能组织特异性的调控大鼠GCLC基因的转录,该元件可能是决定GCLC基因存在组织差异性表达的重要顺式作用元件。 展开更多
关键词 Γ-谷氨酰半胱氨酸合成酶 氧化应激 E-box元件 组织特异性转录 大鼠
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A high-voltage SOI MOSFET with a compensation layer on the trenched buried oxide layer
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作者 赵秋明 李琦 +1 位作者 唐宁 李勇昌 《Journal of Semiconductors》 EI CAS CSCD 2013年第3期31-34,共4页
A new silicon-on-insulator(SOI) high-voltage MOSFET structure with a compensation layer on the trenched buried oxide layer(CL T-LDMOS) is proposed.The high density inverse interface charges at the top surface of the b... A new silicon-on-insulator(SOI) high-voltage MOSFET structure with a compensation layer on the trenched buried oxide layer(CL T-LDMOS) is proposed.The high density inverse interface charges at the top surface of the buried oxide layer(BOX) enhance the electric field in the BOX and a uniform surface electric field profile is obtained,which results in the enhancement of the breakdown voltage(BV).The compensation layer can provide additional P-type charges,and the optimal drift region concentration is increased in order to satisfy the reduced surface electric field(RESURF) condition.The numerical simulation results indicate that the vertical electric field in the BOX increases to 6 MV/cm and the B V of the proposed device increases by 300%in comparison to a conventional SOI LDMOS,while maintaining low on-resistance. 展开更多
关键词 trenched buried oxide layer breakdown voltage ON-RESISTANCE compensation layer
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Effects of Influencing Factors on Fenton Oxidation of Antibiotic Pharmaceutical Wastewater by a Statistical Design Approach 被引量:1
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作者 赵俊杰 祁佩时 +1 位作者 刘云芝 林娜 《Journal of Donghua University(English Edition)》 EI CAS 2013年第1期26-33,共8页
A series of batch-scale experiments were completed to investigate the effects of operational parameters on chemical oxygen demand (COD) removal by Fenton reagent for antibiotic pharmaceutical wastewater (APW). The sig... A series of batch-scale experiments were completed to investigate the effects of operational parameters on chemical oxygen demand (COD) removal by Fenton reagent for antibiotic pharmaceutical wastewater (APW). The significance of five operational factors including the mass ratio of H2O2/COD (g/g), the mole ratio of H2O2/Fe2+ (mol/mol), initial pH, oxidation temperature T, and reaction time t were evaluated statistically by Box-Behnken design (BBD). It was found that the five parameters were all significant to the COD removal efficiency by t-test, as well as the interactions between mass ratio/reaction time and oxidation temperature/reaction. The optimal COD removal efficiency (89.50%) was achieved when the mass ratio of H2O2/COD and the mole ratio of H2O2/Fe2+ were 3.00 and 5.00 respectively, with pH value of 3.68 at 298K for 72min reaction. A quadratic regression model with 0.9907 regression coefficient (R2) was developed which had good agreement to the experimental data. 展开更多
关键词 Fenton oxidation response surface methodology (RSM) box-Behnken design (BBD) antibiotic pharmaceutical wastewater (APW)
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Correlation of serum HMGB1 and sTLT-1 contents with oxidative stress response and endothelial injury in patients with ischemic stroke
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作者 Xiao-Peng Zhang 《Journal of Hainan Medical University》 2017年第21期135-138,共4页
Objective: To study the correlation of serum HMGB1 and sTLT-1 contents with oxidative stress response and endothelial injury in patients with ischemic stroke. Methods: The patients who were diagnosed with ischemic str... Objective: To study the correlation of serum HMGB1 and sTLT-1 contents with oxidative stress response and endothelial injury in patients with ischemic stroke. Methods: The patients who were diagnosed with ischemic stroke in Zhouzhi County People's Hospital between February 2015 and March 2017 were selected as the stroke group of the study, and healthy subjects who received physical examination during the same period were selected as the control group of the study. Serum was collected to determine the contents of HMGB1, sTLT-1, oxidative stress reaction molecules and endothelial injury molecules. Results: Serum HMGB1, sTLT-1, vWF, vWF-cp, sTM, ET-1, D-D, 8-OHdG, LPO and NOS contents of stroke group were significantly higher than those of control group while T-SOD and GSH-Px contents were significantly lower than those of control group;serum T-SOD and GSH-Px contents of stroke patients with high HMBG-1 content were significantly lower than those of stroke patients with low HMBG-1 content while 8-OHdG, LPO and NOS contents were significantly higher than those of stroke patients with low HMBG-1 content;serum vWF, vWF-cp, sTM, ET-1 and D-D contents of stroke patients with high sTLT-1 content were significantly higher than those of stroke patients with low sTLT-1 content. Conclusion: The abnormally elevated HMGB1 and sTLT-1 in serum of patients with ischemic stroke can induce oxidative stress response and aggravate endothelial injury. 展开更多
关键词 Ischemic stroke High mobility group box 1 TRIGGERING receptor EXPRESSED on MYELOID cells-like transcript-1 oxidative stress response Endothelial injury
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鹿茸多肽对骨质疏松模型大鼠的改善作用及对SIRT1/FOXO1信号通路的影响 被引量:3
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作者 迟雪婷 黄晓巍 +5 位作者 陈芳园 周高峰 王晋冀 律广富 林喆 龚庆 《吉林大学学报(医学版)》 CAS CSCD 北大核心 2024年第1期120-127,共8页
目的:探讨鹿茸多肽(VAP)对骨质疏松(OP)模型大鼠的保护作用,并阐明其可能的作用机制。方法:60只12周龄SD大鼠随机分为对照组、模型组、阳性药组(1 mg·kg^(-1)·d^(-1)阿仑膦酸钠灌胃)、低剂量(100 mg·kg^(-1)·d^(-1)... 目的:探讨鹿茸多肽(VAP)对骨质疏松(OP)模型大鼠的保护作用,并阐明其可能的作用机制。方法:60只12周龄SD大鼠随机分为对照组、模型组、阳性药组(1 mg·kg^(-1)·d^(-1)阿仑膦酸钠灌胃)、低剂量(100 mg·kg^(-1)·d^(-1))VAP组、中剂量(200 mg·kg^(-1)·d^(-1))VAP组和高剂量(300 mg·kg^(-1)·d^(-1))VAP组,每组10只。除对照组外,其余各组大鼠肌肉注射地塞米松(2 mg·kg^(-1))复制OP大鼠模型,对照组大鼠肌肉注射等体积生理盐水,每周2次,连续11周。双能X射线骨密度仪检测各组大鼠股骨骨密度(BMD),酶联免疫吸附试验(ELISA)法检测各组大鼠血清中血钙(Ca^(2+))、血磷(P)、骨保护素(OPG)、碱性磷酸酶(ALP)和骨钙素(OCN)水平,生化法检测各组大鼠血清中丙二醛(MDA)水平和超氧化物歧化酶(SOD)活性,HE染色观察各组大鼠骨组织病理形态表现,Western blotting法检测各组大鼠骨组织中沉默信息调节因子1(SIRT1)、过氧化氢酶(CAT)、Runt相关转录因子2(RUNX2)和叉头框蛋白O1(FOXO1)蛋白表达水平。结果:与对照组比较,模型组大鼠股骨BMD明显降低(P<0.05);与模型组比较,阳性药组、中剂量VAP组和高剂量VAP组大鼠股骨BMD明显升高(P<0.05或P<0.01)。与对照组比较,模型组大鼠血清中Ca^(2+)、P和OPG水平及SOD活性明显降低(P<0.05),ALP、OCN和MDA水平明显升高(P<0.05);与模型组比较,低剂量VAP大鼠血清中OPG水平明显升高(P<0.05),阳性药组、中剂量VAP组和高剂量VAP组大鼠血清中Ca^(2+)、P和OPG水平及SOD活性明显升高(P<0.05或P<0.01),阳性药组和各剂量VAP组大鼠血清中ALP、OCN和MDA水平明显降低(P<0.05或P<0.01)。HE染色,与对照组比较,模型组大鼠骨组织中骨细胞数量减少且排列混乱,骨小梁纤细,出现大片断裂,髓腔扩大;与模型组比较,阳性药组、中剂量VAP组和高剂量VAP组大鼠骨组织中骨小梁粗壮,排列紧密。Western blotting法,与对照组比较,模型组大鼠骨组织中SIRT1、CAT、RUNX2和FOXO1蛋白表达水平明显降低(P<0.05);与模型组比较,阳性药组、中剂量VAP组和高剂量VAP组大鼠骨组织中SIRT1、CAT、RUNX2和FOXO1蛋白表达水平明显升高(P<0.05或P<0.01)。结论:VAP对OP模型大鼠具有保护作用,其作用机制可能与介导SIRT1/FOXO1信号通路抗氧化应激作用有关。 展开更多
关键词 骨质疏松症 地塞米松 鹿茸多肽 氧化应激 沉默信息调节因子1 叉头框蛋白O1 信号通路
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穿心莲内酯调节HMGB1/RAGE信号通路对糖尿病周围神经病变大鼠坐骨神经功能损伤的影响 被引量:1
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作者 孙跃先 王九妹 +1 位作者 崔新刚 于晶 《中国药房》 CAS 北大核心 2024年第5期572-577,共6页
目的探讨穿心莲内酯调节高迁移率族蛋白B1(HMGB1)/晚期糖基化终产物受体(RAGE)信号通路对糖尿病周围神经病变(DPN)大鼠坐骨神经功能损伤的影响。方法将84只大鼠随机分为对照组(生理盐水)、DPN组(生理盐水)、穿心莲内酯低剂量组(0.833 mg... 目的探讨穿心莲内酯调节高迁移率族蛋白B1(HMGB1)/晚期糖基化终产物受体(RAGE)信号通路对糖尿病周围神经病变(DPN)大鼠坐骨神经功能损伤的影响。方法将84只大鼠随机分为对照组(生理盐水)、DPN组(生理盐水)、穿心莲内酯低剂量组(0.833 mg/kg)、穿心莲内酯高剂量组(3.332 mg/kg)、硫辛酸组(阳性对照,0.1 g/kg)、重组大鼠HMGB1蛋白(rHMGB1,8μg/kg)组、穿心莲内酯高剂量+rHMGB1组,每组12只。除对照组外,其余各组大鼠均采用高糖高脂饲料喂养联合腹腔注射链脲佐菌素的方式构建DPN模型。造模成功24 h后,进行给药处理,每天1次,持续8周。给药结束后,检测大鼠空腹血糖、机械痛阈值、热痛阈值、坐骨神经传导速度的变化;观察大鼠坐骨神经病理变化;检测大鼠坐骨神经中超氧化物歧化酶(SOD)活性及丙二醛(MDA)含量;检测大鼠坐骨神经中HMGB1、RAGE蛋白表达水平和核因子κB p65(NF-κB p65)蛋白磷酸化水平。结果与对照组比较,DPN组大鼠坐骨神经病理损伤严重,空腹血糖、热痛阈值、MDA含量及HMGB1、RAGE蛋白表达水平和NF-κB p65蛋白磷酸化水平均显著升高(P<0.05),机械痛阈值、感觉神经传导速度、运动神经传导速度、SOD活性显著降低/减慢(P<0.05);与DPN组比较,穿心莲内酯低、高剂量组和硫辛酸组大鼠上述指标均显著改善(P<0.05),rHMGB1组对应指标变化趋势与上述3个给药组相反(P<0.05);并且,rHMGB1可减弱高剂量穿心莲内酯对DPN大鼠血糖的降低作用及坐骨神经氧化应激损伤的改善作用(P<0.05)。结论穿心莲内酯可能通过抑制HMGB1/RAGE信号通路来降低血糖、抑制氧化应激,进而改善DPN大鼠坐骨神经损伤。 展开更多
关键词 穿心莲内酯 糖尿病周围神经病变 高迁移率族蛋白B1 晚期糖基化终产物受体 坐骨神经 氧化应激
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下调XBP1s通过Sirt3/SOD2/mtROS轴减轻缺氧/复氧诱导的肾小管上皮细胞衰老 被引量:1
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作者 彭宣 倪海强 +1 位作者 顾世琦 宫念樵 《器官移植》 CSCD 北大核心 2024年第1期46-54,共9页
目的探讨剪接型X-盒结合蛋白1(XBP1s)在缺氧/复氧(H/R)诱导的原代肾小管上皮细胞衰老中的作用及机制。方法将原代肾小管上皮细胞分为空白对照组(NC组)、H/R组、空载腺病毒阴性对照组(Ad-shNC组)、靶向沉默XBP1s腺病毒组(Ad-shXBP1s组)... 目的探讨剪接型X-盒结合蛋白1(XBP1s)在缺氧/复氧(H/R)诱导的原代肾小管上皮细胞衰老中的作用及机制。方法将原代肾小管上皮细胞分为空白对照组(NC组)、H/R组、空载腺病毒阴性对照组(Ad-shNC组)、靶向沉默XBP1s腺病毒组(Ad-shXBP1s组)、空载腺病毒+H/R处理组(Ad-shNC+H/R组)、靶向沉默XBP1s腺病毒+H/R处理组(Ad-shXBP1s+H/R组)。检测NC组、H/R组、Ad-shNC组、Ad-shXBP1s组XBP1s的表达情况。检测Ad-shNC组、Ad-shNC+H/R组、Ad-shXBP1s+H/R组β-半乳糖苷酶染色情况,细胞衰老标志物p53、p21、γH2AX表达情况,氧化应激相关指标活性氧(ROS)、丙二醛(MDA)和超氧化物歧化酶(SOD)水平。采用染色质免疫共沉淀验证XBP1s转录调控沉默信息调节因子3(Sirt3),检测下调XBP1s后Sirt3及下游SOD2表达,采用流式细胞术检测线粒体活性氧簇(mt ROS)。结果与NC组比较,H/R组XBP1s表达增多;与Ad-sh NC组比较,Ad-sh XBP1s组XBP1s表达减少(均为P<0.001)。与Adsh NC组比较,Ad-sh NC+H/R组β-半乳糖苷酶染色阳性细胞数增加,p53、p21、γH2AX表达增多,ROS、MDA、mt ROS水平升高,SOD活性下降,Sirt3表达量降低,Ac-SOD2/SOD2比值升高;与Ad-sh NC+H/R组相比,Ad-sh XBP1s+H/R组β-半乳糖苷酶染色阳性细胞数减少,p53、p21、γH2AX表达减少,ROS、MDA、mt ROS水平下降,SOD活性升高,Sirt3表达量升高,Ac-SOD2/SOD2比值下降(均为P<0.05)。结论下调XBP1s可减轻H/R诱导的原代肾小管上皮细胞衰老,可能是通过Sirt3/SOD2/mt ROS信号轴发挥作用。 展开更多
关键词 肾移植 缺血-再灌注损伤 剪接型X盒结合蛋白1 细胞衰老 氧化应激 沉默信息调节因子3 线粒体活性氧簇 超氧化物歧化酶
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双埋氧绝缘体上硅SRAM铀离子单粒子效应研究
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作者 王春林 高见头 +5 位作者 刘凡宇 陈思远 王娟娟 王天琦 李博 倪涛 《现代应用物理》 2024年第4期40-46,58,共8页
随着集成电路技术的进步,提高电路的单粒子翻转(single event upset,SEU)阈值变得愈发困难。双埋氧层绝缘体上硅(double silicon-on-insulator,DSOI)技术为单粒子加固技术提供了新方法。利用哈尔滨工业大学空间地面模拟装置(space envir... 随着集成电路技术的进步,提高电路的单粒子翻转(single event upset,SEU)阈值变得愈发困难。双埋氧层绝缘体上硅(double silicon-on-insulator,DSOI)技术为单粒子加固技术提供了新方法。利用哈尔滨工业大学空间地面模拟装置(space environment simulation and research infrastructure,SESRI)产生的铀离子对中国科学院微电子研究所研制的DSOI静态随机存取存储器(static random access memory,SRAM)开展了SEU效应研究。铀离子是目前可获得的线性能量传递(linear energy transfer,LET)最高的重离子。2种不同SEU加固能力的DSOI 4 kbit SRAM试验结果显示,通过对NMOS和PMOS的背栅实施独立偏压控制,可实现DSOI SRAM电路抗SEU能力的宽范围调制。最优条件下,使用LET为118 MeV·cm ^(2)·mg^(-1)的铀离子,累积注量为1×10^(7) cm^(-2)时,被测器件无SEU发生。 展开更多
关键词 绝缘体上硅 双埋氧层绝缘体上硅 静态随机存储器 单粒子效应 单粒子翻转
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锰掺杂DSA电极及其对印染废水处理的过程优化
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作者 朱连燕 周幸福 《化工进展》 EI CAS CSCD 北大核心 2024年第6期3459-3467,共9页
以Ti/SnO_(2)-Sb形稳电极(DSA)为基底,采用浸渍法制备负载有活性层的Ti/SnO_(2)-Sb/SnO_(2)-Sb-Mn电极并进行了表征。利用box-behnken实验设计及响应曲面分析法,探讨槽压、搅拌速率、电极间距这三个因素对亚甲基蓝电催化脱色效率的影响... 以Ti/SnO_(2)-Sb形稳电极(DSA)为基底,采用浸渍法制备负载有活性层的Ti/SnO_(2)-Sb/SnO_(2)-Sb-Mn电极并进行了表征。利用box-behnken实验设计及响应曲面分析法,探讨槽压、搅拌速率、电极间距这三个因素对亚甲基蓝电催化脱色效率的影响,并建立相应的多元二次回归模型,方差分析结果表明,模型的拟合效果好,影响因素的显著性顺序依次为:槽压>电极间距>搅拌速率。验证实验结果显示,当槽压为4.8V、搅拌速率为320r/min、电极间距为1.5cm时,亚甲基蓝的脱色效果达到最佳,此时脱色率达到99.3%,模型的预测值非常接近实验值,验证了该方法的可行性和有效性,可为电催化脱色处理印染废水提供一定的技术指导。 展开更多
关键词 box-behnken响应曲面法 锰掺杂DSA电极 电催化氧化 脱色 印染废水
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新型排水用轴向中空壁聚氯乙烯埋地管力学性能试验及数值分析
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作者 唐鹏飞 胡少伟 +3 位作者 潘福渠 叶宇霄 侯兆光 何宗院 《中南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第4期1509-1522,共14页
为了研究埋地轴向中空壁塑料排水管的变形与力学响应特性,以便充分利用材料与结构性能,基于模型箱试验,获得埋地管道受到土荷载、地面荷载和管土相互作用下管道及其管周土体的力学及其变形特性;基于ABAQUS有限元分析管截面在埋地外压、... 为了研究埋地轴向中空壁塑料排水管的变形与力学响应特性,以便充分利用材料与结构性能,基于模型箱试验,获得埋地管道受到土荷载、地面荷载和管土相互作用下管道及其管周土体的力学及其变形特性;基于ABAQUS有限元分析管截面在埋地外压、排水内压及两者组合作用下的应力和变形特性,建立管道的基本力学参数在砂箱试验与真实埋地条件下的换算关系,提出边界效应修正计算公式。研究结果表明:土柱法+分布角法适用于计算地面静荷载作用下埋地结构壁管道的管顶竖向压力,荷载扩散角宜取30°~35°;在地面静荷载作用下,管道径向变形计算方法中Spangler-Iowa公式偏保守,AWWA M23规范计算结果与试验结果较吻合,而考虑准永久值系数会导致变形计算结果偏小;在埋土外压作用下,管腰位置内壁易发生受压破坏;排水时,管顶位置内壁易发生受拉破坏;内外壁起主要承载作用,受力较大;中间筋主要起连接作用,受力时应力以中性轴为零点向两侧呈梯度增加;本文提出的边界效应修正计算公式是准确可行的。研究成果可为轴向中空壁塑料管等柔性埋地管道的结构设计、力学和损伤失效分析提供参考。 展开更多
关键词 轴向中空壁塑料管 砂箱埋地试验 力学性能 有限元分析 边界效应
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针对某车尿素喷嘴喷射量变小问题的分析与改进
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作者 田占勇 赵超越 +2 位作者 杨燕楠 范明果 蔡君辉 《内燃机与配件》 2024年第5期15-17,共3页
商用车国六产品投放初期,某主机厂重型车辆出现尿素喷嘴喷射量变小问题,造成发动机排气后处理系统故障灯常亮,通过拆检尿素喷嘴,发现其内部存在堵塞物。本文针对该问题提出了排气后处理系统优化改进方案,通过拆检尿素喷嘴结构、取样尿... 商用车国六产品投放初期,某主机厂重型车辆出现尿素喷嘴喷射量变小问题,造成发动机排气后处理系统故障灯常亮,通过拆检尿素喷嘴,发现其内部存在堵塞物。本文针对该问题提出了排气后处理系统优化改进方案,通过拆检尿素喷嘴结构、取样尿素液样品分析、尿素溶液浸泡铝板以及拆检尿素箱进行电镜分析等方法,发现尿素喷嘴喷孔内壁均可见黑色、黑褐色沉积物,其主要为含铝的氧化物以及与其他成分混合,最后对优化改进后的车辆进行了跟踪验证。试验结果表明,车辆未再出现上述现象,验证了改进措施的可行性,对日后实际设计工作具有一定借鉴意义。 展开更多
关键词 排气后处理系统 尿素箱 尿素喷嘴 喷射量 堵塞物 含铝氧化物 电镜分析
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