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Sickle Cell Disease in the Zinder Region in 2023: Prevalence and Sociodemographic Factors
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作者 Brah Moustapha Maman Amadou Djibrilla-Almoustapha +3 位作者 Moustapha Elhadji-Chefou Illa Hamidine Moussa Diongolé Hassane Badé Malam-Abdou 《Open Journal of Blood Diseases》 2024年第1期1-7,共7页
Introduction: In view of the number of sickle cell patients and due to a low production of descriptive studies, we decided to determine the prevalence of genes S and C of the disease in the Zinder region. The objectiv... Introduction: In view of the number of sickle cell patients and due to a low production of descriptive studies, we decided to determine the prevalence of genes S and C of the disease in the Zinder region. The objective was to contribute to improving the management of sickle cell disease in Zinder. Methodology: This was a systematic screening by the “Sickle Scan” test of any blood donor admitted to the Zinder Regional Blood Transfusion Center during the 6-month study period, from January to June 2023. The Sickle Scan is a qualitative lateral flow chromatography immunoassay using whole blood samples that aid in the rapid diagnosis of sickle cell disease. Results: The study was carried out on 613 samples during the period concerned. The frequency of sickle cell genes was 26.9% (n = 165) in all samples collected, with 23.1% (n = 142) and 3.8% (n = 23) for the S gene and the C gene, respectively. The 18 - 30 age group was the most represented with 64.4% (n = 395) cases. The median age of blood donors was 26 years ± 10 years (min = 18 years/max = 60 years). The sex ratio was 2.5. Donors of Nigerien nationality accounted for 84.1% (n = 516). There is a predominance of blood donors with an average monthly income between 34,000 and 70,000 CFA francs in 44.3% (n = 272), lived in permanent housing with drinking water supply. Sickle cell trait (SMA) was found in 22.5% (n = 138). Conclusion: The analysis of these results highlights a high frequency of the S gene for sickle cell disease. The population with an average monthly income is the most affected, with a male predominance. 展开更多
关键词 Sickle cell Anemia Blood Donors Sickle scan
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Scan Cell Positioning for Boosting the Compression of Fan-Out Networks
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作者 Ozgur Sinanoglu Mohammed Al-Mulla +1 位作者 Noora A.Shunaiber Alex Orailoglu 《Journal of Computer Science & Technology》 SCIE EI CSCD 2009年第5期939-948,共10页
Ensuring a high manufacturing test quality of an integrated electronic circuit mandates the application of a large volume test set. Even if the test data can be fit into the memory of an external tester, the consequen... Ensuring a high manufacturing test quality of an integrated electronic circuit mandates the application of a large volume test set. Even if the test data can be fit into the memory of an external tester, the consequent increase in test application time reflects into elevated production costs. Test data compression solutions have been proposed to address the test time and data volume problem by storing and delivering the test data in a compressed format, and subsequently by expanding the data on-chip. In this paper, we propose a scan cell positioning methodology that accompanies a compression technique in order to boost the compression ratio, and squash the test data even further. While we present the application of the proposed approach in conjunction with the fan-out based decompression architecture, this approach can be extended for application along with other compression solutions as well. The experimental results also confirm the compression enhancement of the proposed methodology. 展开更多
关键词 scan-based testing test data compression scan cell reordering scan architecture design
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SCANNING ELECTRON MICROSCOPIC STUDY OF FETAL CHICKEN CALVARIAL OSTEOBLAST-LIKE CELLS CULTURED IN VITRO 被引量:1
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作者 柴本甫 汤雪明 +1 位作者 徐荣辉 朱雅萍 《Medical Bulletin of Shanghai Jiaotong University》 CAS 1993年第2期54-59,共6页
Three types of osteoblast-like cells with different cnfigurations could be ob-tained through culturing fetal chicken calvaria in vitro. They were spindle-shaped cells,globular cells, and polygonal or squamous cells. W... Three types of osteoblast-like cells with different cnfigurations could be ob-tained through culturing fetal chicken calvaria in vitro. They were spindle-shaped cells,globular cells, and polygonal or squamous cells. With passage of culture time, there werechanges in configuration so that the spindle-shaped cells and the globular cells turnedgradually into squamous cells, in quantity which increased greatly to produce confluenceand multi-layer formation of cells, and in function as evidenced by emergence ofintracytoplasmic granules, reflecting collagen synthesis. 展开更多
关键词 osteoblast-like cells FETAL CHICKEN CALVARIA in VITRO scanning electron microscope
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TiO<sub>2</sub>Nanoparticles Induced Genotoxicity in Cultured Cells Using Atmospheric Scanning Electron Microscopy (ASEM)
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作者 Shigeru Sato Takashi Takaki +1 位作者 Hidetoshi Nishiyama Tokuya Omi 《Journal of Cosmetics, Dermatological Sciences and Applications》 2013年第1期121-123,共3页
Nano-sized titanium oxide nanoparticles (TiO2 NPs) are widely used as a dye in food and cosmetics. TiO2 NPs are known to induce DNA damage when incorporated into cells. However, no bioassay is currently available to e... Nano-sized titanium oxide nanoparticles (TiO2 NPs) are widely used as a dye in food and cosmetics. TiO2 NPs are known to induce DNA damage when incorporated into cells. However, no bioassay is currently available to easily determine the cell incorporation of TiO2 NPs or related DNA damage, and to date, few studies have examined the different degrees of incorporation into cells according to the size of the TiO2 NPs particles and the presence or absence of cell specificity regarding DNA damage. This present study was therefore designed to examine COS7 cells that had incorporated TiO2 NPs using atmospheric scanning electron microscopy (ASEM). The results indicated that absorption of TiO2 NPs into cells and nuclear abnormalities had occurred. ASEM is a rapid and simple technique that enables the observation of samples immediately after fixation with glutaraldehyde and staining with phosphotungstic acid, and this method was suggested to be useful in screening for DNA damage. 展开更多
关键词 COS7 cells TiO2 ATMOSPHERIC scanning Electron MICROSCOPY (ASEM) NANOPARTICLE
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Observations of Wood Cell Walls with a Scanning Probe Microscope
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作者 Manami Yamashita Masato Yoshida +2 位作者 Miyuki Matsuo Saori Sato Hiroyuki Yamamoto 《Materials Sciences and Applications》 2016年第10期644-653,共11页
Scanning Probe Microscopes (SPMs) observe specimen surfaces with probes by detecting the physical amount of a material between the cantilever and the surface. SPMs have a high resolution and can measure mechanical cha... Scanning Probe Microscopes (SPMs) observe specimen surfaces with probes by detecting the physical amount of a material between the cantilever and the surface. SPMs have a high resolution and can measure mechanical characteristics such as stiffness, adsorptive properties, and viscoelasticity. These features make it easy to identify the surface structure of complex materials;therefore, the use of SPMs has increased in recent years. Wood cell walls are primarily composed of cellulose, hemicellulose, and lignin. It is believed that hemicellulose and lignin surround the cellulose framework;however, their detailed formation remains unknown. Therefore, we observed wood cell walls via scanning probe microscopy to try to reveal the formation of the cellulose framework. We determined that the size of the cellulose microfibril bundle and hemicellulose lignin module composite was 18.48 nm based on topography and that the size of the cellulose microfibril bundle was 15.33 nm based on phase images. In the viscoelasticity image, we found that the viscoelasticities of each cell wall of the same cell were not the same. This is because the cellulose microfibrils in each cell wall lean in different directions. The angle between the leaning of the cellulose microfibril and the cantilever affects the viscoelasticity measurement. 展开更多
关键词 scanning Probe Microscope Wood cell Wall cellulose Microfibril HEMIcellULOSE LIGNIN
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微流体压力驱动的扫描电化学池显微镜长时间稳定成像
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作者 王志武 庄健 +2 位作者 宁少慧 程磊 郑强强 《光学精密工程》 EI CAS CSCD 北大核心 2024年第10期1528-1537,共10页
为了提升扫描电化学池显微镜(SECCM)对复杂形貌表面电化学活性成像能力,以及避免探针尖端微液滴蒸发和结晶,进而实现长时间、稳定成像,构建了基于纳米移液管探针微流体压力驱动的扫描电化学成像系统。对探针尖端开口处的微液滴流量补偿... 为了提升扫描电化学池显微镜(SECCM)对复杂形貌表面电化学活性成像能力,以及避免探针尖端微液滴蒸发和结晶,进而实现长时间、稳定成像,构建了基于纳米移液管探针微流体压力驱动的扫描电化学成像系统。对探针尖端开口处的微液滴流量补偿、复杂表面形貌同步电化学活性成像可靠性等进行了研究。首先,构建了基于移液管探针微流体压力驱动的SECCM扫描成像系统。接着,建立了移液管微流体压力驱动的探针检测数值模型,研究了探针末端背压与探针尖端流体流量间的关系。然后,在理论模型分析的基础上,实验测试了微流体驱动新方法对具有较大表面形貌特征的玻碳电极材料和铝合金材料表面高分辨率形貌和电化学活性同步成像能力。实验结果表明:新方法可对硬质材料表面(样品表面高度起伏为探针开口直径20倍以上)实现长时间、稳定的电化学成像。新系统的研制将为研究人员在材料电化学、金属材料腐蚀研究提供强有力的工具。 展开更多
关键词 扫描电化学池显微镜 局部高分辨率 循环伏安测量 形貌 电化学活性
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基于金字塔池化网络的质子交换膜燃料电池气体扩散层组分推理方法
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作者 王虎 尹泽泉 +6 位作者 王雯婕 黄笠舟 方宁宁 隋俊友 张加乐 张锐明 隋邦傑 《重庆大学学报》 CAS CSCD 北大核心 2024年第1期84-92,共9页
针对质子交换膜燃料电池气体扩散层(gas diffusion layer composition,GDL)形貌划分与制备工艺改进问题,提出了一种基于金字塔池化网络(pyramid scene parsing network,PSPNet)与多层感知器(multi-layer perception,MLP)的气体扩散层组... 针对质子交换膜燃料电池气体扩散层(gas diffusion layer composition,GDL)形貌划分与制备工艺改进问题,提出了一种基于金字塔池化网络(pyramid scene parsing network,PSPNet)与多层感知器(multi-layer perception,MLP)的气体扩散层组分识别与比例推理方法:首先将带标签的气体扩散层扫描电镜(scanning electron microscope,SEM)图片输入神经网络,得到特征图;得到的图像特征层进入金字塔池化模块后,获取SEM图像的深层和浅层特征;随后将深层和浅层特征图层融合输入全卷积网络(fully convolutional network,FCN)模块,得到预测图像;最后统计各个组分上的像素点比例,通过MLP完成组分比例推理。结果表明:所提方法组分识别像素准确率达81.24%;在5%偏差范围内,比例推理准确率为88.89%。该方法解决了气体扩散层多组分无法区分、比例无法获知的问题,可有效应用于气体扩散层的质检、数值重构以及制备工艺改进。 展开更多
关键词 质子交换膜燃料电池 气体扩散层制备 扫描电镜 人工智能 金字塔池化网络 多层感知器
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AlSc15中间合金中Al_(3)Sc金属间化合物的电化学行为及对局部腐蚀的影响
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作者 蒋伟 高坤元 +6 位作者 胡秀华 文胜平 黄晖 吴晓蓝 魏午 聂祚仁 启世亮 《轻合金加工技术》 CAS 2024年第2期54-58,共5页
将过共晶AlSc15合金加热至液态,以10℃/h速率冷却得到毫米级尺寸的Al_(3)Sc金属间化合物。利用微区电化学和扫描开尔文探针力显微镜(SKPFM)研究了Al_(3)Sc金属间化合物在不同pH值的0.1 mol/L NaCl溶液中的电化学特征及对局部腐蚀敏感性... 将过共晶AlSc15合金加热至液态,以10℃/h速率冷却得到毫米级尺寸的Al_(3)Sc金属间化合物。利用微区电化学和扫描开尔文探针力显微镜(SKPFM)研究了Al_(3)Sc金属间化合物在不同pH值的0.1 mol/L NaCl溶液中的电化学特征及对局部腐蚀敏感性的影响。结果表明,Al_(3)Sc金属间化合物存在自钝化现象,且在碱性环境中有明显的维钝区域;随着pH值的增加,Al_(3)Sc腐蚀电位逐渐降低,在中性和碱性条件下的腐蚀速率明显低于酸性条件下的;Al_(3)Sc金属间化合物与周围铝基体之间的伏打电位差约为40 mV,在铝合金中可能作为较弱的局部阴极,对电偶腐蚀的影响不大。 展开更多
关键词 Al_(3)Sc金属间化合物 微电化学技术 扫描开尔文 局部腐蚀
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MRI平扫及增强扫描对肾癌病理亚型的鉴别价值分析
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作者 张尧 张彬 《中国医学工程》 2024年第2期74-79,共6页
目的分析MRI平扫及增强扫描对肾癌病理亚型的鉴别价值。方法回顾性分析2017年2月至2023年4月安阳市人民医院收治的114例肾癌患者的临床资料,所有患者均经病理检查证实为肾癌且治疗前均接受过磁共振成像(MRI)平扫及增强扫描。比较各病理... 目的分析MRI平扫及增强扫描对肾癌病理亚型的鉴别价值。方法回顾性分析2017年2月至2023年4月安阳市人民医院收治的114例肾癌患者的临床资料,所有患者均经病理检查证实为肾癌且治疗前均接受过磁共振成像(MRI)平扫及增强扫描。比较各病理亚型肾癌患者MRI平扫及增强扫描表现,并以病理结果为“金标准”,评价MRI平扫及增强扫描在肾癌病理亚型中的鉴别价值。结果pRCC和cRCC患者ADC值低于ccRCC患者(P<0.05);cRCC患者T1WI和T2WI平扫低、等信号占比高于ccRCC和pRCC患者(P<0.05),混杂信号占比低于ccRCC和pRCC患者(P<0.05)。pRCC和cRCC患者不均匀强化占比低于ccRCC患者(P<0.05),且cRCC患者不均匀强化占比低于pRCC患者(P<0.05);不同病理亚型强化程度分布差异有统计学意义(P<0.05),ccRCC以重度强化为主,pRCC以轻中度强化为主,cRCC均为轻度强化患者;pRCC和cRCC患者皮质期、实质期、延迟期信号强度变化均低于ccRCC患者(P<0.05),且pRCC患者以上各期信号强度变化均低于cRCC患者(P<0.05)。MRI平扫及增强扫描联合鉴别ccRCC的灵敏度、准确度均高于单项鉴别(P<0.05);MRI平扫及增强扫描联合鉴别pRCC的特异度、准确度均高于单项鉴别(P<0.05),灵敏度高于MRI平扫单项鉴别(P<0.05);MRI平扫及增强扫描联合鉴别cRCC准确度高于单项鉴别(P<0.05)。结论不同病理亚型肾癌患者的MRI平扫及增强扫描表现存在差异,且MRI平扫及增强扫描联合鉴别肾癌病理亚型的价值较高。 展开更多
关键词 肾癌 磁共振成像 平扫 增强扫描 病理亚型 鉴别价值
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术前多排螺旋CT三期增强扫描对非小细胞肺癌纵隔淋巴结转移的诊断价值
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作者 张磊 米玉霞 王建业 《实用癌症杂志》 2024年第1期83-86,共4页
目的探讨多排螺旋CT(MSCT)三期增强扫描对非小细胞肺癌(NSCLC)纵隔淋巴结转移(MLNM)中的术前诊断价值。方法回顾性分析80例NSCLC患者的临床资料,术前均行MSCT三期增强扫描,以术后病理结果为金标准,使用Kappa一致性检验评价MSCT三期增强... 目的探讨多排螺旋CT(MSCT)三期增强扫描对非小细胞肺癌(NSCLC)纵隔淋巴结转移(MLNM)中的术前诊断价值。方法回顾性分析80例NSCLC患者的临床资料,术前均行MSCT三期增强扫描,以术后病理结果为金标准,使用Kappa一致性检验评价MSCT三期增强扫描在术前诊断MLNM的诊断效能。结果术后病理检查证实80例NSCLC患者中,N0期31例,N1期24例,N2期25例,其中MLNM 25例(31.25%);术前MSCT诊断N0期34例,N1期24例,N2期22例,术前MSCT对NSCLC患者N分期诊断与术后病理一致性一般(Kappa=0.735);25例合并MLNM患者中,术前MSCT确诊19例,其对NSCLC患者MLNM的诊断与病理结果一致性一般(Kappa=0.531),其诊断的灵敏度、特异度、准确度、阳性预测值和阴性预测值分别为76.00%、80.00%、78.75%、63.33%和88.00%;纵隔淋巴结转移率在不同肿瘤直径、胸膜凹陷与否、不同肿大淋巴结位置、累及粗大肺静脉与否以及不同淋巴结短径的NSCLC患者间比较均有统计学意义(P<0.05)。结论术前MSCT三期增强扫描诊断NSCLC患者MLNM具有一定的准确性,结合原发病灶大小、胸膜凹陷、肿大淋巴结位置、累及粗大肺静脉等多方面信息可为淋巴结清扫提供重要参考。 展开更多
关键词 非小细胞肺癌 多排螺旋CT 增强扫描 纵隔淋巴结 转移
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枯草芽孢杆菌无细胞上清液抑制单增李斯特菌生物被膜形成的研究
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作者 胡安祺 杨慧轩 +5 位作者 姚现琦 董鹏程 朱立贤 罗欣 张一敏 刘昀阁 《食品与发酵工业》 CAS CSCD 北大核心 2024年第13期1-8,共8页
单增李斯特菌(Listeria monocytogenes)是一种常见的食源性致病菌,其生物被膜是导致食品污染和疾病传播的重要原因。该研究选用枯草芽孢杆菌(Bacillus subtilis)无细胞上清液(cell free supernatant,CFS)作为抑制剂,探究B.subtilis CFS... 单增李斯特菌(Listeria monocytogenes)是一种常见的食源性致病菌,其生物被膜是导致食品污染和疾病传播的重要原因。该研究选用枯草芽孢杆菌(Bacillus subtilis)无细胞上清液(cell free supernatant,CFS)作为抑制剂,探究B.subtilis CFS在抑制L.monocytogenes野生菌株118(以下简称No.118)生物被膜方面的作用和潜力。首先测定了B.subtilis CFS的最小抑菌浓度(minimum inhibitory concentration,MIC),接着采用结晶紫染色法测定了不同亚最小抑菌浓度下B.subtilis CFS对No.118的生物被膜抑制率,发现不同亚抑菌浓度下的CFS对No.118生物被膜均具有显著的抑制作用,且在1/64 MIC时生物被膜抑制率仍可达到47%;同时B.subtilis CFS对No.118生物被膜代谢活性、自聚集率、表面疏水性、群集泳动能力和膜外聚合物分泌也均有显著抑制作用;最后,通过激光共聚焦显微镜观察了在CFS作用下,No.118生物被膜结构和细胞分布的变化规律,经CFS处理后,No.118生物被膜结构松散,细菌数量明显减少。综上,B.subtilis CFS可通过影响No.118生物被膜细胞的代谢活性、自聚集能力和群集泳动能力以及膜外聚合物的分泌来抑制其生物被膜形成,对探究益生菌代谢产物作为生物被膜抑制剂方面的应用具有重要的参考价值。 展开更多
关键词 枯草芽孢杆菌 无细胞上清液 单增李斯特菌 生物被膜 激光共聚焦显微镜
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CT增强扫描对评估肾透明细胞癌病理分期准确性及手术指导价值的探讨
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作者 刘居上 王亚楠 《黑龙江医学》 2024年第3期293-296,共4页
目的:探讨CT增强扫描对评估肾透明细胞癌病理分期的准确性及手术指导价值,为临床提供参考。方法:选取2021年3月—2022年3月河南科技大学第一附属医院收治的126例肾透明细胞癌患者作为研究对象,根据手术病理组织活检结果将不同病理分期... 目的:探讨CT增强扫描对评估肾透明细胞癌病理分期的准确性及手术指导价值,为临床提供参考。方法:选取2021年3月—2022年3月河南科技大学第一附属医院收治的126例肾透明细胞癌患者作为研究对象,根据手术病理组织活检结果将不同病理分期患者分为A组(30例,病理诊断为Ⅰ期)、B组(35例,病理诊断为Ⅱ期)、C组(31例,病理诊断为Ⅲ期)、D组(30例,病理诊断为Ⅳ期)。所有患者均接受CT平扫及增强扫描,比较不同扫描方式下不同病理分期的检出情况,比较4组患者在不同扫描方式下的成像特征及CT值。结果:CT增强扫描下,不同病理分期患者的检出率均高于CT平扫,差异有统计学意义(χ^(2)=14.398、13.226、9.517、22.222,P<0.05);增强扫描下,4组患者的CT值差异有统计学意义(F=14.900,P<0.05);增强扫描下,Ⅳ期患者的病灶血管组织侵犯率、转移率均高于其他患者。结论:CT增强扫描可通过观察CT值、周围组织血管侵犯及远处转移情况而实现对肾透明细胞癌患者病理分期的准确评估,结合CT增强扫描结果可有效指导患者手术治疗,对改善患者预后具有重要意义。 展开更多
关键词 肾透明细胞癌 CT增强扫描 病理分期 成像特征 手术指导
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CT增强扫描结合外显体LncRNA RP5-977B1对于非小细胞肺癌诊断和预后的价值研究
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作者 王钺 李晓冬 +1 位作者 王睿 张银文 《中国CT和MRI杂志》 2024年第6期65-67,81,共4页
目的 分析CT增强扫描结合外显体长链非编码RNA(LncRNA)RP5-977B1对于非小细胞肺癌(NSCLC)诊断和预后价值。方法 选择2018年5月~2019年5月本院收治的80例NSCLC患者为NSCLC组,另外选择同期收治的80例肺部良性疾病患者为对照组,均给予CT增... 目的 分析CT增强扫描结合外显体长链非编码RNA(LncRNA)RP5-977B1对于非小细胞肺癌(NSCLC)诊断和预后价值。方法 选择2018年5月~2019年5月本院收治的80例NSCLC患者为NSCLC组,另外选择同期收治的80例肺部良性疾病患者为对照组,均给予CT增强扫描,获得强化峰值(PH)、肿块强化达峰时间(Tp)、灌注值;采用实时荧光聚合酶链式反应(RT-PCR)检测患者血清外显体LncRNA RP5-977B1的表达情况;采用门诊或电话的方式对NSCLC患者随访3年。末次随访时间为2022年5月31日,将患者分为生存组(n=49)和死亡组(n=31),采用受试者工作曲线(ROC)分析CT增强扫描结合外显体LncRNA RP5-977B1对NSCLC的诊断和预后评估价值。结果 相较于对照组,NSCLC组PH、 Tp、灌注值、LncRNA RP5-977B1表达水平均明显较高(P<0.05),ROC曲线显示,CT增强扫描参数联合LncRNA RP5-977B1对诊断NSCLC的效能最高,AUC为0.929;相较于死亡组,生存组PH、Tp、灌注值、LncRNA RP5-977B1表达水平均明显较低(P<0.05),ROC曲线显示,CT增强扫描参数联合LncRNA RP5-977B1对评估NS CLC患者预后的效能最高,AUC为0.925。结论 CT增强扫描参数和LncRNA RP5-977B1表达水平在NSCLC患者均明显升高,其联合对诊断NSCLC和评估患者预后具有较高的价值。 展开更多
关键词 CT增强扫描 外显体LncRNA RP5-977B1 非小细胞肺癌 诊断 预后
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Influence of PTFE on Electrode Structure for Performance of PEMFC and 10-Cells Stack 被引量:1
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作者 LIN Rui ZHAO Tiantian +3 位作者 ZHANG Haiyan CAO Chunhui LI Bing MA Jianxin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第6期1171-1175,共5页
Water plays a critical role on the performance, stability and lifetime of proton exchange membrane fuel cells(PEMFCs). The addition of poly tetrafluoroethylene(PTFE) to the gas diffusion layer, especially, the cat... Water plays a critical role on the performance, stability and lifetime of proton exchange membrane fuel cells(PEMFCs). The addition of poly tetrafluoroethylene(PTFE) to the gas diffusion layer, especially, the cathode side, would optimize the transportation of water, electron and gas and thus improve the performance of the fuel cell. But until now, the studies about directly applying the PTFE to the catalyst layer are rarely reported. In this paper, the membrane electrode is fabricated by using directly coating catalyst to the membrane method(CCM) and applying PTFE directly to the cathode electrode catalyst layer. The performance of the single cell is determined by polarization curves and durability tests. Electrochemical impedance spectroscopy(EIS) and scanning electron microscopy(SEM) techniques are used to characterize the electrochemical properties of PEMFC. Also the performance of a 10-cells stack is detected. Combining the performance and the physical-chemistry characterization of PEMFC shows that addition of appropriate content of PTFE to the electrode enhances the performance of the fuel cell, which may be due to the improved water management. Addition of appropriate content of PTFE enhances the interaction between the membrane and the catalyst layer, and bigger pores and highly textured structure form in the MEA, which favors the oxygen mass transfer and protons transfer in the fuel cell. While superfluous addition of PTFE covers the surface of catalysts and hindered the contact of catalyst with Nation, which leads to the reduction of electrochemical active area and the decay of the fuel cell performance. The proposed research would optimize the water management of the fuel cell and thus improve the performance of the fuel cell. 展开更多
关键词 proton exchange membrane fuel cell poly-tetrafluoroethylene electrochemical impedance spectroscopy scanning electron microscopy fuel cell stack
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Comparative ultrastructural study of endoplasmic reticulum in colorectal carcinoma cell lines with different degrees of differentiation
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作者 Shu Feng Jin Dan Song 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第4期569-571,共3页
INTRODUCTIONThe endoplasmic reticulum(ER)consists of a complexsystem of tubules,lamellae,and flattened vesicles,andhas a variety of morphologies in different cells.It isbelieved to play a central role in the biosynthe... INTRODUCTIONThe endoplasmic reticulum(ER)consists of a complexsystem of tubules,lamellae,and flattened vesicles,andhas a variety of morphologies in different cells.It isbelieved to play a central role in the biosynthesis ofcholesterol,phospholipids, steroids, prostaglandins, 展开更多
关键词 COLORECTAL NEOPLASMS endoplasmic reticulum ULTRASTRUCTURE microscopy electron scanning cell DIFFERENTIATION
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Spiral CT localization of pancreatic function-ing islet cell tumors 被引量:4
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作者 Qing Xu, Wen-Hua Chen and Qing-Juan Huang Nanjing, China Department of Radiology, First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China Department of Radiology, Third Affiliated Hospital of Suzhou Univer- sity, Changzhou 213003, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2004年第4期616-619,共4页
BACKGROUND: Surgeons are always concerned about the localization of pancreatic functioning islet cell tumor. If the tumor is accurately localized before operation, resection of the pancreatic body and tail without int... BACKGROUND: Surgeons are always concerned about the localization of pancreatic functioning islet cell tumor. If the tumor is accurately localized before operation, resection of the pancreatic body and tail without intention can be avoided. The purpose of this study was to evaluate spiral CT localization of pancreatic functioning islet cell tumors and CT techniques. METHODS: CT manifestations in 6 patients with clinically and pathologically proved pancreatic functioning islet cell tumors ware analyzed retrospectively. RESULTS: In 4 patients with insulinomas and 2 patients with glucagonomas, 5 were localized accurately by CT be- fore surgery and 1 was detected retrospectively. The en- hancement of tumors was greater than that of normal pan- creas in arterial phase and pancreatic parenchymal phase. Four patients showed mild high-density and 2, iso-density in the portal venous phase. CONCLUSION: Spiral CT multi-phase enhanced scan with 1.5 ml/kg contrast agent and 2-5 mm slice width can loca- lize functioning islet cell tumors accurately. 展开更多
关键词 islet cell tumor spiral CT enhanced scan
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Effects of drug serum of anti-fibrosis I herbal compound on calcium in hepatic stellate cell and its molecular mechanism 被引量:4
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作者 Yong-HongXiao Dian-WuLiu QingLi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第10期1515-1520,共6页
AIM: To investigate the effects of anti-fibrosis I herbal compound on intracellular Ca2+ in activated hepatic stellate cell (HSC) and to try to survey its molecular mechanism in treatment and prevention of hepatic fib... AIM: To investigate the effects of anti-fibrosis I herbal compound on intracellular Ca2+ in activated hepatic stellate cell (HSC) and to try to survey its molecular mechanism in treatment and prevention of hepatic fibrosis and portal hypertension.METHODS: The activated HSC line was plated on small glass cover slips in 24 wells culture dishes at a density of 5x106/mL, and incubated in RPMI-1640 media for 24 h.After the cells were loaded with Fluo-3/AM, intracellular Ca2+ was measured with laser scanning confocal microscopy (LSCM). The dynamic changes of intracellular Ca2+,stimulated by carbon tetrachloride, TGF-β1 antibody and the drug serum of anti-fibrosis I herbal compound and under orthogonal design were determined by LSCM. The effect of anti-fibrosis I herbal compound on intracellular Ca2+ was observed before and after the addition of TGF-β1antibody.RESULTS: The intracellular Ca2+ were significantly different in different dosage of carbon tetrachloride anti-fibrosis Iformula drug serum, TGF-β1 antibody and different turn of these substance, but their interval time between CCl4and TGF-β1 antibody, CCl4 and anti-fibrosis I drug serum had no influence on intracellular Ca2+. The result showed intracellular Ca2+ wasn't significantly different between rat serum without anti-fibrosis I and untreated group.After carbon tetrachloride stimulation, intracellular Ca2+ of activated HSC increased significantly when the dosage of CCl4 from 5 to 15 mmol/L, however, decreased significantly after stimulation by 5-20 μg/mL TGF-β1antibody or 5-20 mL/L drug serum. Moreover, before and after the addition of TGF-β1 antibody, intracellular Ca2+was significantly different. These results suggested that the molecular mechanism was independent of blocking TGF-β1 effects.CONCLUSION: Anti-fibrosis I herbal compound may treat hepatic fibrosis and decrease portal hypertension by inhibiting activated HSC contractility through decrease of intracellular Ca2+. 展开更多
关键词 抗纤维化药 中草药 肝脏星状细胞 分子机制 钙离子 肝纤维 高血压
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Effect of solanine on the membrane potential of mitochondria in HepG_2 cells and [Ca^(2+)]i in the cells 被引量:17
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作者 Shi-Yong Gao Qiu-Juan Wang Yu-Bin Ji 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第21期3359-3367,共9页
瞄准:在 HepG (2 ) 房间在线粒体的膜电位上观察茄硷的效果,并且揭开并且[Ca (2+)] 在房间的(i) 茄硷由导致 apoptosis 的机制。方法:HepG (2 ) 房间是双的与 AO/EB 染色了,并且房间的词法变化被观察使用激光共焦的扫描显微镜学(LCS... 瞄准:在 HepG (2 ) 房间在线粒体的膜电位上观察茄硷的效果,并且揭开并且[Ca (2+)] 在房间的(i) 茄硷由导致 apoptosis 的机制。方法:HepG (2 ) 房间是双的与 AO/EB 染色了,并且房间的词法变化被观察使用激光共焦的扫描显微镜学(LCSM ) 。HepG (2 ) 房间与 TMRE 被染色,并且在在房间的线粒体的膜电位的变化用 LCSM 被观察。HepG (2 ) 房间是双的与 Fluo-3/AM,和变化染色了[Ca (2+)] 在房间的(i) 用 LCSM 被观察。HepG (2 ) 房间是双的染色了与 TMRE 和 Fluo-3/AM,和两个在线粒体和的膜电位的变化[Ca (2+)] 在房间的(i) 用 LCSM 被观察。结果:在对待的组的房间显示出 apoptosis 的典型符号。与 TMRE 染色显示出那茄硷能更低的膜电位;与 Fluo-3/AM 染色证明茄硷能在肿瘤房间增加 Ca (2+) 的集中;并且那些两倍与 TMRE 和 Fluo-3/AM 染色证明当它降低了线粒体的膜电位,茄硷能在一样的时间在房间增加 Ca (2+) 的集中。结论:茄硷由降低膜电位在膜开创磅隧道,导致 Ca (2+) 在它的集中坡度下面被搬运,它接着在房间导致 Ca (2+) 的集中的上升,打开为 apoptosis 的机制。 展开更多
关键词 病理机制 茄碱 电位 线立体 形态学
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VISUALIZATION OF DYNAMIC ORGANIZATION OF CYTOSKELETON GELS IN LIVING CELLS BY HYBRID-SPM 被引量:4
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作者 K.Kawabata Y.Sado +4 位作者 M.Nagayama T.Nitta K.Nemoto Y.Koyama H.Haga 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2003年第2期169-174,共6页
We succeeded in performing of hybrid Scanning Probe Microscopy (hybrid-SPM) in which mechanical-SPM andfluorescence microscopy are combined. This technique is able to measure simultaneously mechanical properties anddi... We succeeded in performing of hybrid Scanning Probe Microscopy (hybrid-SPM) in which mechanical-SPM andfluorescence microscopy are combined. This technique is able to measure simultaneously mechanical properties anddistribution of cytoskeletons of living cells by using green fluorescent protein. We measured evolution of both local elasticityand distributions of actin stress fibers in an identical fibroblast living in physiological conditions. The SPM experimentsrevealed that stiffer lines develop in living cells, which correspond to actin stress fibers. The elasticity of the actin stressfibers is as high as 100 kPa. We discuss mechanical effects on the development of actin filament networks. 展开更多
关键词 scanning probe microscopy Green fluorescent protein FIBROBLAST cell migration Cytoskeleton ELASTICITY
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Diagnostic of Flooding and Hysteresis Phenomena for Proton Exchange Membrane Fuel Cell using Cyclo-Voltammogram Simulation
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作者 Der-Sheng Chan Kan-Lin Hsueh 《Journal of Chemistry and Chemical Engineering》 2011年第10期863-872,共10页
关键词 滞后现象 质子交换膜燃料 洪水 电池使用 多孔电极 模拟 伏安 诊断
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