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Single dose of ibutilide for conversion of persistent atrial fibrillation after radiofrequency ablation

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Chinese Medical Journal 2011年第5期124卷 710-713页

作者： HOU Yu FANG Pi-hua LIU Jun LI Xiao-feng HU ji-qiang ZHANG shu Clinical EP Lab and Arrhythmia Center Fuwai Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100037 China

Background Patients with persistent or permanent atrial fibrillation （AF） often need direct current cardioversion after radiofrequency ablation. The aim of this study was to investigate the effectiveness and safety of ibutilide for cardioversion of persistent or permanent atrial fibrillation after radiofrequency ablation and the factors related to conversion. Methods Patients with persistent or permanent atrial fibrillation were treated with combined ablation strategy including circumferential pulmonary vein isolation, linear ablation and CAFE potential ablation. If AF was not terminated after ablation, ibutilide was used for cardioversion （1 mg, intravenous injection in 10 minutes）. These patients were divided into a conversion group and a non-conversion group according to whether AF was converted to sinus rhythm within 30 minutes after administration. ECG monitoring was performed during the injection of ibutilide. Atrial waves recorded by coronary sinus electrodes were measured for calculating average wavelength of AF waves in six seconds. The QT interval was measured immediately after conversion and 2 hours after injection of *** Forty patients whose AF was not converted to sinus rhythm after radiofrequency ablation were given an intravenous injection of ibutilide. Of the 40 patients, 29 cases were converted to sinus rhythm, with a conversion rate of 72.5%. The average conversion time was （13.2±5.5） minutes. Compared with the conversion group, patients in the non-conversion group had a longer history of AF （9.4±5.3） years vs. （4.3±2.8） years, P 〈0.05）, and a markedly enlarged left atrium （47.3±2.9） mm vs. （42.1±4.5） mm, P〈0.05）. There were no significant differences in gender, age, body mass index and left ventricular function between the two groups. Ibutilide significantly prolonged the average wavelength of the AF wave （171.8±29.5） ms vs. （242.0±40.0） ms, P 〈0.001）. Two hours after ibutilide treatment, the QT interval was significantly shortened （

关键词： ibutilide conversion atrial fibrillation radiofrequency ablation

Narrow-bandgap materials for optoelectronics applications

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Frontiers of physics 2022年第1期17卷 89-121页

作者： Xiao-Hui Li Yi-Xuan Guo Yujie Ren jia-Jun Peng ji-shu Liu Cong Wang Han Zhang School of Physics&Information Technology Shaanxi Normal UniversityXi’an710119China Shenzhen Key Laboratory of Two-Dimensional Materials and Devices/Shenzhen Engineering Laboratory of Phosphorene and Optoelectronics Collaborative Innovation Center for Optoelectronic Science and TechnologyKey Laboratory of Optoelectronic Devices and Systems of Ministry of Education and GuangdongShenzhen518060China

Narrow-bandgap materials possess the intriguing optical-electric properties and unique structures,which can be widely applied in the field of photonics,energy optoelectronic sensing and biomedicine,***,the researches on nonlinear optical properties of narrow-bandgap materials have attracted extensive attention *** this paper,we review the progress of narrow-bandgap materials from many aspects,such as background,nonlinear optical properties,energy band structure,methods of preparation,and *** materials have obvious nonlinear optical characteristics and the interaction with the short pulse laser excitation shows the extremely strong nonlinear absorption characteristics,which leads to the optical limiting or saturable absorption related to Pauli blocking and excited state ***,some of these novel narrow-bandgap materials have been utilized for the generation of ultrashort pulse that covers the range from the visible to mid-infrared wavelength ***,the study on these materials paves a new way for the advancement of optoelctronics devices.

关键词： narrow-bandgap materials saturable absorber ultrafast lasers modulator photodetectors

Neuroprotection by cattle encephalon glycoside and ignotin beyond the time window of thrombolysis in ischemic stroke

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Neural Regeneration Research 2021年第2期16卷 312-318页

作者： Jun Zhong Rong-Wei Li Ju Wang Ying Wang Hong-Fei Ge ji-shu Xian Hua Feng Liang Tan Department of Neurosurgery Southwest HospitalThe Third Military Medical University(Army Medical University)ChongqingChina Department of Neurosurgery Hanzhong Central HospitalHanzhongShaanxi ProvinceChina Department of Oncology Hanzhong Central HospitalHanzhongShaanxi ProvinceChina State Key Laboratory of Power Transmission Equipment and System Security and New Technology School of Electrical EngineeringChongqing UniversityChongqingChina

Cattle encephalon glycoside and ignotin(CEGI)injection is known as a multi-target neuroprotective drug that contains numerous liposoluble molecules,such as polypeptides,monosialotetrahexosyl ganglioside(GM-1),free amino acids,hypoxanthine and *** has been approved by the Chinese State Food and Drug Administration and widely used in the treatments of various diseases,such as stroke and Alzheimer's ***,the neuroprotective effects of CEGI beyond the time window of thrombolysis(within 4.5 hours)on acute ischemic stroke remain *** study constructed a rat middle cerebral artery occlusion model by suture-occluded method to simulate ischemic *** first daily dose was intraperitoneally injected at 8 hours post-surgery and the CEGI treatments continued for 14 *** of the modified five-point Bederson scale,beam balance test and rotameric test showed the neurological function of ischemic stroke rats treated with 4 m L/kg/d CEGI improved significantly,but the mortality within 14 days did not change *** MRI and 2,3,5-triphenyltetrazolium chloride staining confirmed that the infarct size in the 4 m L/kg/d CEGI-treated rats was significantly reduced compared with ischemic insult *** results of transmission electron microscopy and double immunofluorescence staining showed that the hippocampal neuronal necrosis in the ischemic penumbra decreased whereas the immunopositivity of new neuronal-specific protein doublecortin and the percentage of Ki67/doublecortin positive cells increased in CEGI-treated rats compared with untreated *** results suggest that CEGI has an effective neuroprotective effect on ischemic stroke when administered after the time window of *** study was approved by the Animal Ethics Committee of The Third Military Medical University,China.

关键词： apoptosis brain cattle encephalon glycoside and ignotin central nervous system neurological function plasticity rat regeneration stroke

Morphological Filters and Wavelet-based Histogram Equalization Image Enhancement for Weak Target Detection

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红外技术 2003年第4期25卷 32-38页

作者：吉书鹏 Dept.ofElectronicEngineering TsinghuaUniversityBeijing100084China；Optical-electricitytechnologydevelopmentcenter.HenanLuoyang471009China

Image enhancement methods are typically aimed at improvement of the overall visibility of features. Though histogram equalization can enhance the contrast by redistributing the gray levels, it has the drawback that it reduces the information in the processed image. In this paper, we present a new image enhancement algorithm. After histogram equalization is carried out, morphological filters and wavelet-based enhancement algorithm is used to clean out the unwanted details and further enhance the image and compensate for the information loss during histogram equalization. Experimental results show that the morphological filters and wavelet-based histogram equalization algorithm can significantly enhance the contrast and increase the information entropy of the image.

关键词：弱目标检测形态滤波小波变换图像增强算法

苯乙烯-丁二烯-苯乙烯嵌段共聚物/橡胶粉/碳九石油树脂复合改性高黏沥青的黏附性

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合成橡胶工业 2024年第4期47卷 342-346页

作者：孙吉书濮夏天肖田郭艳芳王松河北工业大学土木与交通学院天津300401 天津市市政工程设计研究院天津300051 河北水利电力学院交通工程系河北沧州061001

为了改善高黏改性沥青与集料之间的黏附性,制备了基于碳九石油树脂、苯乙烯-丁二烯-苯乙烯嵌段共聚物和橡胶粉的高黏改性沥青(HVAM-2),采用滴定法测定了其与集料之间的接触角并计算出黏附功。通过冻融劈裂试验、浸水飞散试验和汉堡车辙... 详细信息

为了改善高黏改性沥青与集料之间的黏附性,制备了基于碳九石油树脂、苯乙烯-丁二烯-苯乙烯嵌段共聚物和橡胶粉的高黏改性沥青(HVAM-2),采用滴定法测定了其与集料之间的接触角并计算出黏附功。通过冻融劈裂试验、浸水飞散试验和汉堡车辙试验进一步验证了HVAM-2混合料的黏附性。结果表明,碳九石油树脂、苯乙烯-丁二烯-苯乙烯嵌段共聚物和橡胶粉三种材料在沥青中形成的网格结构能够大幅度提高沥青的黏附性,有效改善沥青与集料之间的黏接能力;相比于基质沥青,HVAM-2的黏附功提高了72.9%,且HVAM-2沥青混合料具有良好的水稳定性。

关键词：改性沥青碳九石油树脂苯乙烯-丁二烯-苯乙烯嵌段共聚物橡胶粉黏附性水稳定性

Preparation of β-methyl p-iodophenyl pentadecanoicacid (BMIPP) and ^(125)I-BMIPP

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Nuclear Science and Techniques 2000年第4期11卷 240-246页

作者： WU Chun-Ying, ji shu-Ren, LU Chun-Xiong (National Laboratory of Nuclear Medicine, jiangsu Institute of Nuclear Medicine, Wuxi 214063) 江苏省核医学所核医学国家重点实验室江苏无锡 214063

A method with several steps superior to literature has been developed for the preparation of B-methyl p-iodophenyl pentadecanoic acid(BMIPP). The synthesis and physical properties of BMIPP are described. It is characterized by IR, 1HNMR, elemental analysis and MS. 125I-BMIPP can be prepared by three methods: direct labeling, solid-state transfer labeling and Cu(I ) assisted labeling. Cu(I) assisted labeling is simple and not necessary to purify before clinical use. It can fulfil the requirements for kit labeling.

关键词： ^125I-BMIPP 放射性碘标记放射性药物 β-甲基P-碘代苯十五烷酸脂肪酸

Population dynamics and considerations for the conservation of the rare Cycas fairylakea in China

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Forestry Studies in China 2012年第2期14卷 118-123页

作者： WANG Dian-pei PENG Shao-lin CHEN Fei-peng ji shu-yi College of Life Science and Technology Hubei Engineering UniversityXiaogan 432000P.R.China South China Botanical Garden Chinese Academy of SciencesGuangzhou 510650P.R.China College of Life Science Sun Yat-Sen UniversityGuangzhou 510275P.R.China College of Life Science South China Agricultural UniversityGuangzhou 510642P.R.China

Quantitative dynamics and viability of a rare and wild Cycas fairylakea population were studied with a time-specific life table, a Leslie matrix model and a survival function in order to provide scientific guidance for its protection. The results of the time- specific life table show that this C. fairylakea population suffered a high death rate in three age classes, i.e., age class 1 （0-15 years）, V （61-75 years） and VI （76-90 years）. The Leslie matrix model suggests that the number of plants would decline from the present 1613 to 59 per hectare in 150 years. Furthermore, the viability analysis indicates that seedlings have the highest mortality density rate and that middle-aged plants （i.e., 61-75 years, 76-90 years） have high mortality density rate and hazard rate. These conditions affect natural regeneration of the population and lead to a lack of seedlings which in turn causes the extinction of the population. An in situ conservation of the population should be established and protection measures taken as soon as possible.

关键词： Cycasfairylakea population rare species time-specific life table Leslie matrix model viability

The Relationship Between Senescence and Ca^(2+)-ATPase Activity of Microsomal Membrane and Lipid Peroxidation in Harvested Peach Fruit

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Agricultural Sciences in China 2006年第8期5卷 609-614页

作者： GUAN Jun-feng FAN Xiu-cai DOU Shi-juan ZHANG ji-shu LI Guang-min Institute Of Genetics and Physiology Hebei Academy of Agricultural and Forestry Sciences Shijiazhuang 050051 P.R.China Zhengzhou Fruit Institute Chinese Academy of Agricultural Sciences Zhengzhou 450002 P.R.China Northwest A＆F University Yangling 712100 P.R.China

Peach fruit easily soften and have a short storage time at normal temperature. In this study, peach fruit （Prunus persica sieb et Zucc cv. Yingqing） were picked and stored at 25 and 4℃ to investigate the senescence in correlation with Ca^2＋- ATPase activity of microsomal membrane and lipid peroxidation during ripening and senescence. In comparison with that stored at 25~C, the fruit stored at 4℃ exhibited a higher flesh firmness, lower respiration rate, and generated the late bigger peak value of Ca^2＋-ATPase activity as well as maintained the higher activity of the enzyme. Meanwhile, the lower levels of super oxygen radical （O2^-.） production and content of malondialdehyde （MDA）, a product of membrane lipid peroxidation were observed. Sodium orthovanadate （SO） and erythrosin B （EB）, as Ca^2＋-ATPase inhibitors, could stimulate the respiration rate. The results suggested that the slower senescence rate of peach fruit was closely related to the higher peak value and longer duration of Ca^2＋-ATPase activity in microsomal membrane, with the slighter membrane lipid peroxidation and lower O2^-. production rate.

关键词： peach fruit Ca^2+-ATPase active oxygen lipid peroxidation senescence

Performance of Semi-solid Slurry Produced by Twin-screw Stirring Mixer and Rheo-diecasting Process of AZ91D Alloy

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Journal of Wuhan University of Technology(Materials Science) 2004年第3期19卷 81-85页

作者：肖泽辉 Huazhong University of Science and Technology

The microstructure of semi-solid slurry of AZ91D alloy, which was produced by twin-screw stirring mixer under the different parameters, was *** by cold chamber die casting process was performed thereafter. The results indicate that with decreasing of the barrel temperature of the mixer and the pouring temperature of molten Mg alloy, the solid fraction of semi-solid slurry increases and the size of non-dendritic grains becomes smaller. While the shear rate increases, the solid fraction of semi-solid slurry decreases. The tensile strength and elongation of metal rheoformed by die casting are higher by about 37% and 44% respectively than those produced by conventional liquid die casting.

关键词： semi-solid slurry magnesium alloy twin-screw rheoforming die casting