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某型蓄电池工程车主车架结构分析 预览
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作者 葛东坡 徐巍 +3 位作者 张衬英 钟万 万雳 李福金 《装备制造技术》 2019年第5期101-103,110共4页
主车架是蓄电池工程车的关键部件之一,其结构性能好坏直接影响车辆的运行品质和行车安全。以某型蓄电池工程车的主车架为研究对象,建立了主车架的有限元分析模型,确定了主车架上载荷的组合工况,运用ANSYS完成了多种工况下主车架的刚度... 主车架是蓄电池工程车的关键部件之一,其结构性能好坏直接影响车辆的运行品质和行车安全。以某型蓄电池工程车的主车架为研究对象,建立了主车架的有限元分析模型,确定了主车架上载荷的组合工况,运用ANSYS完成了多种工况下主车架的刚度、强度和模态的有限元计算分析,验证了其结构设计的合理性。 展开更多
关键词 蓄电池工程车 主车架 有限元 强度 模态
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炼油厂燃料气回收液化气过程的设计与控制研究 预览
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作者 商先永 薛长勇 +3 位作者 杨义磊 钟旺 朱敏燕 孙兰义 《石油炼制与化工》 CAS CSCD 北大核心 2019年第2期100-105,共6页
以某炼油厂燃料气回收液化气(LPG)为对象,分别对3种LPG回收流程进行了研究。在稳态模拟的基础上,以年总费用为优化目标,优化了各流程的主要工艺参数。结果表明,隔壁塔流程较另外两种流程的年总费用分别降低37.66%和11.35%,表现出较大的... 以某炼油厂燃料气回收液化气(LPG)为对象,分别对3种LPG回收流程进行了研究。在稳态模拟的基础上,以年总费用为优化目标,优化了各流程的主要工艺参数。结果表明,隔壁塔流程较另外两种流程的年总费用分别降低37.66%和11.35%,表现出较大的经济优势。此外,对炼油厂燃料气回收LPG隔壁塔流程的动态特性进行了研究,提出的四点温度控制结构能够有效地抵抗进料扰动,具有良好的可控性。由此可见,隔壁塔在炼油厂燃料气回收LPG工艺中具有非常高的应用潜力。 展开更多
关键词 液化气 过程设计 隔壁塔 动态控制
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Effects of dietary phosphorous supplementation on laying performance,egg quality,bone health and immune responses of laying hens challenged with Escherichia coli lipopolysaccharide 预览
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作者 Wei Nie Bo Wang +2 位作者 Jing Gao Yuming Guo Zhong Wang 《畜牧与生物技术杂志:英文版》 SCIE CAS CSCD 2018年第4期980-990,共11页
Background:Phosphorus is an essential nutrient to maintain poultry health and performance.The objective of this study was to evaluate the effect of dietary phosphorus levels on egg production,egg quality,bone health,i... Background:Phosphorus is an essential nutrient to maintain poultry health and performance.The objective of this study was to evaluate the effect of dietary phosphorus levels on egg production,egg quality,bone health,immune responses of laying hens challenged with Escherichia coli lipopolysaccharide.Methods:Three hundred laying hens at 28 wk were randomly divided into 2 dietary treatments with 10 replicates of 15 birds.The wheat-soybean based diets contained either 0.12%or 0.4%non-phytate phosphorus(NPP).At 32 wk of age,all the birds of each dietary treatment were injected into the abdomen with 1.5 mg/kg body weight(BW)of either LPS or saline once a day at 24-h intervals for continuous 9 d.The performance of laying hens was evaluated for 9 d.The eggs after the fifth injection were collected to value the egg quality.Three hours after the first injection,blood was collected to measure serum metabolite and immune response associated parameters.Three hours after the fifth injection,the hens were euthanized to obtain tibia,cecal tonsils and jejunum.Results:Compared with saline-injected hens,LPS-injected hens had lower feed intake and egg production(P<0.05).Eggshell thickness,strength,albumin height and Haugh unit were significantly increased in LPS-injected hens compared with saline-injected hens(P<0.05).Furthermore,laying hens challenged with LPS had lower villious height/crypt depth ration than those received saline.Serum calcium,phosphorus and SOD activities significantly decreased in the LPS-injected hens compared with the control(P<0.05).LPS up-regulated expression of IL-1β,IL-6 and IL-10 in cecum,and serum concentration of MDA,IL-1βand IL-6(P<0.05),whereas 0.40%dietary non-phytate phosphorus supplementation significantly increased(P<0.05)villi height/crypt depth ratio,decreased(P<0.05)serum MDA and IFN-γconcentration compared with the 0.12%non-phytate phosphorus group.Conclusion:In summary,this study demonstrates that 0.40%dietary non-phytate phosphorus supplementation significantly increased calcium and phosp 展开更多
关键词 EGG quality Immune response LAYING HENS LIPOPOLYSACCHARIDE Phosphorus
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Comparison between modified lateral supraorbital approach and pterional approach in the surgical treatment of middle cerebral artery aneurysms
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作者 Zhouqing Chen Xiaoou Sun +6 位作者 Tai Lu Zhengyang Lu Ming Jiang Chongshun Zhao Wanchun You Yun Zhu Zhong Wang 《中华神经外科杂志(英文)》 CSCD 2018年第1期1-6,共6页
Background:The Middle cerebral artery (MCA) aneurysm is a common type of craniocerebral aneurysm that is prone to rupture and high mortality. The classic surgical approaches are the Pterional approach and the Lateral ... Background:The Middle cerebral artery (MCA) aneurysm is a common type of craniocerebral aneurysm that is prone to rupture and high mortality. The classic surgical approaches are the Pterional approach and the Lateral Supraorbital (LSO) approach, but there are shortcomings. Methods:This study retrospectively analyzed clinical and imaging data from 181 patients with MCA aneurysm clipping in the Department of Neurosurgery, First Affiliated Hospital of Soochow University between 2011 and 2017. Statistical analysis using parametric and nonparametric tests showed that P values below 0.05 were considered statistically significant. Results: The preoperative GCS score (P=0.003), Hunt-Hess scale (P < 0.001) and the operating habits of the surgeon (P < 0.001) affected the surgeon to choose a surgical approach. The choice of two surgical methods on the operation time (P < 0.001), skin incision (P < 0.001), complications (P=0.026), tracheotomy (P=0.014), prognosis (P=0.002) were significantly different. Different surgical approaches (P=0.002), Hunt-Hess scale (P <0.001), GCS scale (P < 0.001), GCS sorse (P < 0.001), skin incision (P=0.031) and complications (P < 0.001) are closely related to the prognosis of patients. Conclusions: Modified LSO approach provides another surgical approach for MCA aneurysm clipping, while avoiding the drawbacks of the LSO approach in the clipping of MCA distal aneurysm. 展开更多
关键词 ANEURYSM CLIPPING Middle cerebral artery ANEURYSMS MODIFIED LATERAL supraorbital APPROACH LATERAL supraorbital APPROACH Pterional APPROACH
贝克隆变换与几类KdV型方程 预览
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作者 郭晓茵 王忠 +2 位作者 薛汾仪 杨灵娥 周德浩 《理论数学》 2018年第2期121-125,共5页
本文研究了几类KdV型方程之间的贝克隆变换。通过贝克隆变换,本文求得了一类新型KdV方程和一类五阶KdV方程的孤立子解。
关键词 贝克隆变换 KDV方程 孤立子
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Genetic association and epistatic interaction of the interleukin-10 signaling pathway in pediatric inflammatory bowel disease 预览
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作者 Zhenwu Lin Zhong Wang +6 位作者 John P Hegarty Tony R Lin Yunhua Wang Sue Deiling Rongling Wu Neal J Thomas Joanna Floros 《世界胃肠病学杂志:英文版》 SCIE CAS 2017年第27期4897-4909,共13页
AIM To study the genetic association and epistatic interaction of the interleukin(IL)-10 and IL-10/STAT3 pathways in pediatric inflammatory bowel disease(IBD). METHODS A total of 159 pediatric inflammatory IBD patient... AIM To study the genetic association and epistatic interaction of the interleukin(IL)-10 and IL-10/STAT3 pathways in pediatric inflammatory bowel disease(IBD). METHODS A total of 159 pediatric inflammatory IBD patients(Crohn’s disease,n = 136; ulcerative colitis,n = 23) and 129 matched controls were studied for genetic association of selected single nucleotide polymorphisms(SNPs) of the IL-10 gene and the genes IL10 RA,IL10 RB,STAT3,and HO1,from the IL-10/STAT3 signaling pathway. As interactions between SNPs from different loci may significantly affect the associated risk for disease,additive(a) and dominant(d) modeling of SNP interactions was also performed to examine highorder epistasis between combinations of the individual SNPs. RESULTS The results showed that IL-10 rs304496 was associated with pediatric IBD(P = 0.022),but no association was found for two other IL-10 SNPs,rs1800872 and rs2034498,or for SNPs in genes IL10 RA,IL10 RB,STAT3,and HO1. However,analysis of epistatic interaction among these genes showed significant interactions:(1) between two IL-10 SNPs rs1800872 and rs3024496(additive-additive P = 0.00015,Bonferroni P value(Bp) = 0.003);(2) between IL-10 RB rs2834167 and HO1 rs2071746(dominant-additive,P = 0.0018,Bp = 0.039); and(3) among IL-10 rs1800872,IL10 RB rs2834167,and HO1 rs2071746(additivedominant-additive,P = 0.00015,Bp = 0.005),as well as weak interactions among IL-10 rs1800872,IL-10 rs3024496,and IL-10RA(additive-additive-additive,P = 0.003; Bp = 0.099),and among IL10 RA,IL10 RB,and HO1 genes(additive-dominant-additive,P = 0.008,Bp = 0.287).CONCLUSION These results indicate that both the IL-10 gene itself,and through epistatic interaction with genes within the IL-10/STAT3 signaling pathway,contribute to the risk of pediatric IBD. 展开更多
关键词 小儿科的煽动性的肠疾病 INTERLEUKIN-10 HO1 挑选核苷酸多型性 IL10-STAT3 小径 Epistatic 相互作用
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Method Based on Time Randomization to Resist Fault Sensitivity Analysis 预览
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作者 Yingjian Yan Jijun Xu +2 位作者 ShouchengWang ZhongWang Min Liu 《北京理工大学学报:英文版》 EI CAS 2017年第3期411-417,共7页
A fault sensitivity analysis(FSA)-resistance model based on time randomization is proposed.The randomization unit is composed of two parts,namely the configurable register array(R-A)and the decoder(chiefly random numb... A fault sensitivity analysis(FSA)-resistance model based on time randomization is proposed.The randomization unit is composed of two parts,namely the configurable register array(R-A)and the decoder(chiefly random number generator,RNG).In this way,registers chosen can be either valid or invalid depending on the configuration information generated by the decoder.Thus,the fault sensitivity information can be confusing.Meanwhile,based on this model,a defensive scheme is designed to resist both fault sensitivity analysis(FSA)and differential power analysis(DPA).This scheme is verified with our experiments. 展开更多
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Bt基因导入对侵染丛枝菌根真菌的玉米生长生理及磷转运基因表达的影响 预览 被引量:2
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作者 钟旺 曾慧兰 王建武 《中国生态农业学报》 CSCD 北大核心 2017年第8期1198-1205,共8页
为了分析Bt玉米与常规玉米对接种丛枝菌根真菌响应的异同,本文在接种摩西球囊霉(Funneliformis mosseae)和不接种的条件下,对比分析了两个Bt玉米品种‘5422Bt1’(Bt11)和‘5422CBCL’(Mon810)以及同源常规玉米品种‘5422’根系中丛枝菌... 为了分析Bt玉米与常规玉米对接种丛枝菌根真菌响应的异同,本文在接种摩西球囊霉(Funneliformis mosseae)和不接种的条件下,对比分析了两个Bt玉米品种‘5422Bt1’(Bt11)和‘5422CBCL’(Mon810)以及同源常规玉米品种‘5422’根系中丛枝菌根真菌侵染率、磷转运基因的表达量、生长和养分利用状况。结果表明:生长50d和80d时,Bt玉米‘5422Bt1’和‘5422CBCL’根系丛枝菌根真菌侵染率显著高于常规玉米‘5422’,分别比‘5422’高13.54%、11.24%和9.83%、6.70%;50d取样时,接菌和不接菌处理玉米‘5422Bt1’、‘5422CBCL’和‘5422’根系内的磷转运基因表达量均没有显著差异;接菌和不接菌处理下玉米‘5422Bt1’的干重显著高于‘5422CBCL’相应的处理,而与‘5422’没有显著差异;80d取样时,不接菌处理玉米‘5422Bt1’的根长、根表面积和根体积显著高于‘5422’和‘5422CBCL’不接菌处理。Bt基因的导入主要影响了两个Bt玉米品种(‘5422Bt1’和‘5422CBCL’)苗期(50d)和成熟期(80d)的氮素吸收利用,与常规玉米品种‘5422’相比,合成Bt蛋白消耗了部分氮素和磷;3个玉米品种对接种AMF的响应不同,接菌处理提高了‘5422Bt1’和‘5422CBCL’苗期(50d)和成熟期(80d)的氮素吸收利用。在磷养分条件满足玉米生长需要的条件下,接种丛枝菌根真菌对Bt玉米磷转运基因表达量和磷的吸收利用没有显著影响。Bt基因的导入以及接种F.mosseae对Bt玉米生长和养分利用的影响与不同转化事件形成的品种特性相关。 展开更多
关键词 BT玉米 丛枝菌根真菌 生长特性 养分利用 磷转运基因
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基于多元统计分析的城市竞争力研究 预览 被引量:1
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作者 王中 邓琼 王跃恒 《经济数学》 2017年第3期30-34,共5页
应用多元统计分析方法对34个省会城市和计划单列市的竞争力进行了综合评估.首先设立城市竞争力评价指标,由于指标之间存在相关性,采用因子分析法选取公共因子作为评价的综合指标,然后构造评价函数,根据城市竞争力在各公因子上的得分及... 应用多元统计分析方法对34个省会城市和计划单列市的竞争力进行了综合评估.首先设立城市竞争力评价指标,由于指标之间存在相关性,采用因子分析法选取公共因子作为评价的综合指标,然后构造评价函数,根据城市竞争力在各公因子上的得分及其综合排名,分析各城市的发展特色和竞争优劣点.基于因子分析法得到的公因子替代原始变量,分别采用系统聚类分析法和K均值聚类分析法给各城市划分类型,比较两种不同聚类法得出的结果,分析聚类结果可靠性.最后基于综合评估结果给出了提高城市竞争力的合理建议. 展开更多
关键词 区域经济学 竞争力与综合实力正相关 多元统计分析 聚类分析
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高定形聚乙二醇/剑麻纤维素/膨胀石墨相变储能材料的研制及热性能 预览 被引量:4
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作者 贾仕奎 王忠 +3 位作者 陈立贵 李雷权 付蕾 包维维 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2017年第1期137-141,共5页
以聚乙二醇(PEG)作为相变组分,以高导热的膨胀石墨(EG)和富含羟基的剑麻纤维素(CSF)作为相变支撑组分,分别利用自制的超声辅助真空设备进行动态灌注或机械搅拌进行熔融共混制备了不同PEG用量的定形相变储能材料(PCMs)。采用... 以聚乙二醇(PEG)作为相变组分,以高导热的膨胀石墨(EG)和富含羟基的剑麻纤维素(CSF)作为相变支撑组分,分别利用自制的超声辅助真空设备进行动态灌注或机械搅拌进行熔融共混制备了不同PEG用量的定形相变储能材料(PCMs)。采用扫描电子显微镜、高分辨率光学相机、差示扫描量热仪、Hotdisk-导热仪、热重分析仪等技术测试了PEG基复合PCMs的微观形貌、定形性、储热性能、导热率及稳定性。结果表明,新颖的动态灌注法制备的PEG基复合相变材料呈现出更致密的微观形态,更好的储热性能和更高的导热率及热稳定性。同时,实验发现由于CSF大量的极性羟基和多孔隙结构,当CSF质量分数为30%,EG质量分数为1%时,复合材料表现出极好的定形效果。 展开更多
关键词 剑麻纤维素 聚乙二醇 膨胀石墨 动态灌注法
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Application of gemstone spectral imaging for efficacy evaluation in hepatocellular carcinoma after transarterial chemoembolization 预览
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作者 Qi-Yu Liu Chuan-Dong He +6 位作者 Ying Zhou Dan Huang Hua Lin Zhong Wang Dong Wang Jin-Qiu Wang Li-Ping Liao 《世界胃肠病学杂志:英文版》 SCIE CAS 2016年第11期3242-3251,共10页
AIM: To assess the value of gemstone spectral imaging(GSI) in efficacy evaluation in hepatocellular cancer(HCC) after transcatheter arterial chemoembolization(TACE) treatment.METHODS: Thirty patients with HCC underwen... AIM: To assess the value of gemstone spectral imaging(GSI) in efficacy evaluation in hepatocellular cancer(HCC) after transcatheter arterial chemoembolization(TACE) treatment.METHODS: Thirty patients with HCC underwent GSI, including nonenhanced, arterial, portalvenous and delayed phase scans, after TACE treatment. Arterial phase images were acquired with GSI for reconstruction of virtual nonenhanced images and color overlay images. Digital subtraction angiography(DSA) was performed in all these patients. Two blinded and independent readers evaluated the data in two reading sessions; standard nonenhanced, arterial, portalvenous, and delayed phase images were read in session A, and the optimal monochromatic images, iodine/water based images and spectrum features were read in session B. Sensitivity and specificity were calculated with the DSA data as the reference standard. The sensitivity and specificity were compared using the χ2 test.RESULTS: DSA revealed 154 lesions in 30 patients, and 100 of them had blood supply. Overall sensitivity and specificity were 72%( 72/100) and 77.8 %(42/54) for session A, and 97%(97/100) and 94.4%(51/54) for session B, respectively. The sensitivity and specificity of the two reading sessions were significantly different(χ2 = 23.04, χ2 = 7.11, P < 0.05).CONCLUSION: Compared with conventional CT, GSI could significantly improve the detection of small and multiple lesions without increasing the radiation dose. Based on spectrum features, GSI could assess tumor homogeneity and more accurately identify residual tumors and recurrent or metastatic lesions during efficacy evaluation and follow-up in HCC after TACE treatment. 展开更多
关键词 Gemstone SPECTRAL imaging HEPATOCELLULAR carcinoma TRANSCATHETER ARTERIAL CHEMOEMBOLIZATION Digital
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Serration Behavior in Zr-Cu-Al Glass-forming Systems
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作者 Zhong WANG Jiao-jiao LI +3 位作者 Li-wei REN Yong ZHANG Jun-wei QIAO Bao-cheng WANG 《钢铁研究学报:英文版》 SCIE CAS CSCD 2016年第1期42-47,共6页
The metallic glass matrix composites(MGMCs)and bulk metallic glasses(BMGs)were studied by statistical analysis during plastic deformation at the strain rates of 2×10-2,2×10-3,and 2×10-4 s-1,respecti... The metallic glass matrix composites(MGMCs)and bulk metallic glasses(BMGs)were studied by statistical analysis during plastic deformation at the strain rates of 2×10-2,2×10-3,and 2×10-4 s-1,respectively.No serration events occur in both MGMCs and BMGs during compression tests at the strain rate of 2×10-2 s-1.When deformed at the strain rate of 2×10-3 s-1,the BMG displays a larger plasticity,which is due to the larger serration events followed by a series of small serrations caused by the continuous movement of free volume.The amplitudes and elastic-energy densities increase with increasing the strain rates owing to many serrations in MGMCs.It is deduced that the Young′s modulus decreases from the normalized stress drop and fluctuations are observed on stressstrain curves,which is attributed to a lower coefficient according to the stick-slip model. 展开更多
关键词 bulk metallic glass metallic glass matrix composite SERRATION shear band
Application of Polyurethane Curing Barn in Flue-cured Tobacco Production 预览
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作者 Ang LI Qingzhi JANG +2 位作者 Wenjian ZHANG Zhong WANG Jun WAN 《农业生物技术:英文版》 CAS 2016年第2期34-36,39共4页
[Objective] This study aimed to investigate the curing performance of polyurethane curing barn and reduce the cost of tobacco leaf flue-curing.[Method] The temperature control effect,curing effect and curing cost of p... [Objective] This study aimed to investigate the curing performance of polyurethane curing barn and reduce the cost of tobacco leaf flue-curing.[Method] The temperature control effect,curing effect and curing cost of polyurethane curing barn and traditional bulk curing barn were analyzed and compared.[Result] The results showed that there were no significant differences in curing performance between two types of curing barns.Horizontal temperature differences increased slightly as the temperature rose.Specifically,horizontal temperature differences between each layer ranged from 0.2 ℃ to 0.5 ℃.Both two types of curing barns exhibited uniform air distribution.Polyurethane curing barn exhibited stable vertical temperature differences.Both two types of curing barns presented good curing effects with slight differences.Polyurethane curing barn exhibited higher economic benefits,lower coal cost,lower electricity cost,lower labor cost and longer service life than traditional bulk curing barn,but its construction cost was higher.[Conclusion] Polyurethane curing barn exhibits better curing performance with good application prospects. 展开更多
关键词 聚氨酯 酯固化 烤烟生产 应用 密集烤房 发电成本 固化性能 烟叶烘烤
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Self-organized Criticality Behavior in Bulk Metallic Glasses
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作者 Jun-wei QIAO Zhong WANG 《钢铁研究学报:英文版》 SCIE CAS CSCD 2016年第1期7-13,共7页
Serrated flows are known as repeated yielding of bulk metallic glasses(BMGs)during plastic deformation under different loading conditions,which are associated with the operation of shear banding.According to the stati... Serrated flows are known as repeated yielding of bulk metallic glasses(BMGs)during plastic deformation under different loading conditions,which are associated with the operation of shear banding.According to the statistics of some parameters,the shear avalanches can display a self-organized critical state,suggesting a large ductility of BMGs.The emergence of the self-organized criticality(SOC)behavior in different BMGs is due to the temperature,strain rate,and chemical compositions.The SOC behavior is accompanied with the following phenomena:the interactions occur in the shear bands;the incubation time is longer than the relaxation time;the time interval is lacking of typical time scale;and the spatial or temporal parameters should display apower-law distribution. 展开更多
关键词 self-organized criticality behavior bulk metallic glass serrated flow power-law distribution
β3-adrenoceptor Impacts Apoptosis in Cultured Cardiomyocytes via Activation of PI3K/Akt and p38MAPK 预览
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作者 马苗苗 朱晓丽 +7 位作者 王丽 胡小芳 王忠 赵瑾 马依彤 杨毅宁 陈邦党 刘芬 《华中科技大学学报:医学英德文版》 SCIE CAS 2016年第1期1-7,共7页
β3-adrenoceptor(β3-AR) has been shown to promote myocardial apoptosis. However, the exact physiological role and importance of this receptor in the human myocardium, and its underlying mode of action, have not been ... β3-adrenoceptor(β3-AR) has been shown to promote myocardial apoptosis. However, the exact physiological role and importance of this receptor in the human myocardium, and its underlying mode of action, have not been fully elucidated. The present study aimed to determine the effects of β3-AR on the promotion of myocardial apoptosis and on norepinephrine(NE) injury. We analyzed NE-induced cardiomyocyte(CM) apoptosis by using a TUNEL and an annexin V/propidium iodide apoptosis assay. Furthermore, we investigated the NE-induced expression of the apoptosis marker genes Akt and p38 MAPK, their phosphorylated counterparts p-Akt and p-p38 MAPK, caspase-3, Bcl-2, and Bax. In addition, we determined the effect of a 48-h treatment with a β3-AR agonist and antagonist on expression of these marker genes. β3-AR overexpression was found to increase CM apoptosis, accompanied by an increased expression of caspase-3, bax/bcl-2, and p-p38 MAPK. In contrast, the β3-blocker reduced apoptosis of CMs and the associated elevated Akt expression. We identified a novel and potent anti-apoptosis mechanism via the PI3K/Akt pathway and a pro-apoptosis pathway mediated by p38 MAPK. 展开更多
关键词 医学 临床 诊断 症状
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ON THE CAUCHY PROBLEM OF A COHERENTLY COUPLED SCHRODINGER SYSTEM 预览
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作者 王忠 崔尚斌 《数学物理学报:B辑英文版》 SCIE CSCD 2016年第2期371-384,共14页
In this article, we consider the well-posedness of a coherently coupled Schrdinger system with four waves mixing in space dimension n ≤ 4. The Cauchy problem for the cubic system is studied in L~2 for n ≤ 2 and in... In this article, we consider the well-posedness of a coherently coupled Schrdinger system with four waves mixing in space dimension n ≤ 4. The Cauchy problem for the cubic system is studied in L~2 for n ≤ 2 and in H~1 for n ≤ 4. We obtain two sharp conditions between global existence and blow up. 展开更多
关键词 Cauchy problem coherently Schrdinger system global existence
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地埋管道安全埋深研究进展 被引量:1
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作者 高金翎 姚文娟 +2 位作者 刘雄 陶佳丽 钟旺 《地下空间与工程学报》 CSCD 北大核心 2016年第S1期331-342,共12页
管道是自来水、电力、燃气等生活必需品的重要输送工具,将管道埋置在地下合理的深度不仅可以提高管道使用过程中的安全性,还可以达到节约地上空间的目的。随着国民经济的发展,新型材料、大直径、薄壁、长距离的地埋管线结构相继出现,对... 管道是自来水、电力、燃气等生活必需品的重要输送工具,将管道埋置在地下合理的深度不仅可以提高管道使用过程中的安全性,还可以达到节约地上空间的目的。随着国民经济的发展,新型材料、大直径、薄壁、长距离的地埋管线结构相继出现,对地埋管道安全埋深计算理论和方法提出了迫切要求。从土的本构模型、地埋管道垂直土压力计算、管土相互作用、埋管外载、土体类型以及数值模拟六个角度综述了地埋管道安全埋深的研究进展,得出前人研究管道安全埋深问题的思路和方法,同时针对存在的问题进行分析,最后对其未来的发展进行了展望,以期为后续管道安全埋深研究提供科学、新颖、合理的意见和建议。 展开更多
关键词 地埋管道 安全埋深 综述 进展
二期尿道成型术更适合于需要横断尿道板并伴有严重弯曲畸形的近段型尿道下裂
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作者 Da-Chao Zheng Hai-Jun Yao Zhi-Kang Cai Jun Da Qi Chen Yan-Bo Chen Ke Zhang Ming-Xi Xu Mu-Jun Lu Zhong Wang 《亚洲男性学杂志:英文版》 SCIE CAS CSCD 2015年第1期94-97,I0009共5页
对于伴有严重阴茎弯曲的尿道下裂,横断尿道板后是选择一期还是二期手术仍存在争议。这项回顾性研究比较评价了这两种方法的优劣。本研究共收集66例伴有严重阴茎弯曲的近端型尿道下裂的患者,根据手术方式分成两组,其中32例行一期手术... 对于伴有严重阴茎弯曲的尿道下裂,横断尿道板后是选择一期还是二期手术仍存在争议。这项回顾性研究比较评价了这两种方法的优劣。本研究共收集66例伴有严重阴茎弯曲的近端型尿道下裂的患者,根据手术方式分成两组,其中32例行一期手术(Duckett),34例行二期手术。一期和二期手术组的中位年龄分别为7.5岁和11.0岁,中位随访时间分别为28.5个月和35个月。所有患者术后尿道外口均位于龟头顶端。随访期间无患者出现阴茎弯曲复发,患者及其家属对阴茎的长度和外观均满意。术后两组各有8例患者出现并发症,两组间并发症率无统计学差异。一期手术尿道狭窄的远期并发症率高j(18.75%1,JO%)。在一期手术组中,青春期前患者的并发症率显著低于青春期后患者(10.52%w46.15%3。中期随访结果提示,横断尿道板可有效矫正近端型尿道下裂合并的重度阴茎弯曲。考虑到一期手术组中较高的尿道狭窄发生率,本文认为分期手术更适合伴有严重阴茎弯曲需要横断尿道板的近端型尿道下裂。 展开更多
关键词 阴茎弯曲 近端型尿道下裂 一期尿道成形术 二期尿道成形术
Ginsenoside Rd promotes neurogenesis in rat brain after transient focal cerebral ischemia via activation of PI3K/Akt pathway
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作者 Xin-yu LIU Xin-yu ZHOU +4 位作者 Jin-cai HOU Hua ZHU Zhong WANG Jian-xun LIU Yong-qiu ZHENG 《中国药理学报:英文版》 SCIE CAS CSCD 2015年第4期421-428,共8页
瞄准: 在 ischemia/reperfusion 损害(IRI ) 以后在老鼠大脑在神经发生上调查人参皂甙 Rd (Rd ) 的效果。
关键词 局灶性脑缺血 神经发生 人参皂甙 大鼠脑 Akt 缺血/再灌注损伤 信号通路 激活
Effect of dietary nonphytate phosphorus on laying performance and small intestinal epithelial phosphate transporter expression in Dwarf pink-shell laying hens 预览
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作者 Wei Nie Ying Yang +2 位作者 Jianmin Yuan Zhong Wang Yuming Guo 《畜牧与生物技术杂志:英文版》 SCIE 2014年第3期333-339,共7页
This study examined the effects of various levels of dietary nonphytate phosphorus on laying performance and the expression patterns of phosphorus metabolism related genes in Dwarf pink-shell laying hens.A total of 40... This study examined the effects of various levels of dietary nonphytate phosphorus on laying performance and the expression patterns of phosphorus metabolism related genes in Dwarf pink-shell laying hens.A total of 40528-week-old Dwarf pink-shell laying hens were fed the same corn-soybean basal meals but containing 0.20%,0.25%,0.30%,0.35%or 0.40%nonphytate phosphorus.The results showed that feed intake,egg production,and average egg weights were quadratically correlated with dietary nonphytate phosphorus content(P< 0.05),and the highest egg production,feed intake and average egg weights were achieved when dietary nonphytate phosphorus was at 0.3%(P< 0.05).mRNA expression of intestinal sodium phosphorus co-transporter linearly decreased when dietary nonphytate phosphorus increased.mRNA and protein expression of intestinal calbindin and vitamin D receptor correlated quadratically with dietary nonphytate phosphorus,and the highest expression was found when dietary available phosphorus was at 0.25%to 0.3%.In conclusion,the ideal phosphorus requirement for Dwarf pink-shell layer hens is estimated to be 0.3%in a corn-soybean diet.With this level of phosphorus supplementation,calbindin and vitamin D receptor reached their highest expression. 展开更多
关键词 非植酸磷 产蛋性能 粉壳蛋鸡 肠上皮 日粮 转运 粉色 mRNA表达
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