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Effects of L-arginine and N~ω-nitro-L-arginine methylester on learning and memory and α7 nAChR expression in the prefrontal cortex and hippocampus of rats

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Neuroscience Bulletin 2013年第3期29卷 303-310页

作者： xiao-Ming Wei Wei yang Li-xia Liu Wen-Xiu Qi Shanxi Medical University Department of Physiology Nanyang Medical College of Henan Department of Physiology Fenyang College of Shanxi Medical University

Nitric oxide （NO） is a novel type of neurotransmitter that is closely associated with synaptic plasticity, learning and memory. In the present study, we assessed the effects of Larginine and NnitroL arginine methylester （LNAME, a nitric oxide synthase inhibitor） on learning and memory. Rats were assigned to three groups receiving intracerebroventricular injections of LArg （the NO precursor）, LNAME, or 0.9% NaCI （control）, once daily for seven con secutive days. Twelve hours after the last injection, they underwent an electric shockpaired Y maze test. Twentyfour hours later, the rats＇ memory of the safe illuminated arm was tested. After that, the levels of NO and a7 nicotinic acetylcholine receptor （a7 nAChR） in the prefrontal cortex and hippocampus were assessed using an NO assay kit, and immunohistochemistry and Western blots, respectively. We found that, compared to controls, LArgtreated rats received fewer foot shocks and made fewer errors to reach the learning criterion, and made fewer errors during the memorytesting session. In contrast, LNAMEtreated rats received more foot shocks and made more errors than controls to reach the learning criterion, and made more errors during the memorytesting session. In parallel, NO content in the prefrontal cortex and hippocampus was higher in LArgtreated rats and lower inLNAME rats, compared to controls. Similarly, （]7 nAChR immunoreactivity and protein expression in the prefrontal cortex and hippocampus were higher in LArgtreated rats and lower in LNAME rats, compared to controls. These results suggest that the modulation of NO content in the brain correlates with a7 nAChR distribution and expression in the prefrontal cortex and hippocampus, as well as with learning and memory performance in the Ymaze.

关键词： nitric oxide L-arginine N-nitro-L-arginine methylester learning and memory nicotinic acetylcholine receptor cerebral cortex andhippocampus Y-maze

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A systematic review of the effects and mechanisms of preoperative 5α-reductase inhibitors on intraoperative haemorrhage during surgery for benign prostatic hyperplasia

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Asian Journal of Andrology 2011年第6期13卷 812-818页

作者： Huan-Tao Zong xiao-xia Peng Chen-Chen yang Yong Zhang Department of Urology Beijing Chao Yang Hospital University Beijing 100069 China School of Public Health and Family Medicine Capital Medical University Beijing 100069 China

5α-reductase inhibitors （5α-RIs）, including finasteride and dutasteride, are commonly used medical therapies for benign prostatic hyperplasia （BPH）. Many studies reported that preoperative 5α-RI had impact on intraoperative haemorrhage during surgery for BPH, but it was still in controversial. So, we conducted a systematic review of the effects and mechanisms of 5α-RIs on intraoperative bleeding for BPH. MEDLINE, EMBASE, the Cochrane Controlled Trail Register of Controlled Trials and the reference lists of retrieved studies were searched in the analysis. Sixteen publications involving 15 different randomized controlled trials （RCTs） and a total of 1156 patients were used in the analysis, including 10 RCTs for finasteride and five RCTs for dutasteride. We found that preoperative finasteride treatment decreases microvessel density （MVD） in resected prostate specimens. Total blood loss, blood loss per gram of resected prostate tissue and decreases in haemoglobin were all greatly reduced in the finasteride group as compared to controls. Dutasteride appeared to have no effect on bleeding. This meta-analysis shows that preoperative finasteride treatment could decrease intraoperative haemorrhage during surgery for BPH. Preoperative dutasteride had no effect on intraoperative haemorrhage, but further high-qualitv prospective studies are still needed to confirm this observation.

关键词： 5α-reductase inhibitor benign prostate hyperplasia haemorrhage meta-analysis microvessel density

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Analysis of oxide layer structure in nitrided grain-oriented silicon steel

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International Journal of Minerals,Metallurgy and Materials 2019年第12期26卷 1531-1538页

作者： xiao-long Wu xia Li Ping yang Zhi-wei Jia Hai-li Zhang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Iron and Steel Research Institute Angang GroupAnshan 114000China

The production of low-temperature reheated grain-oriented silicon steel is mainly based on the acquired inhibitor *** to the additional nitriding process,a high nitrogen content exists in the oxide layer,which changes the structure of the oxide *** this study,the structure of the surface oxide layer after nitriding was analyzed by scanning electron microscopy(SEM),electron back-scattered diffraction(EBSD),glow discharge spectrometry(GDS),and X-ray diffraction(XRD).The size and orientation of ferritic grains in the oxide layer were characterized,and the distribution characteristics of the key elements along the thickness direction were *** results show that the oxide layer of the steel sample mainly comprised particles of Fe2SiO4 and spherical and lamellar SiO2,and Fe4N and fcc-Fe phases were also ***,the size and orientation of ferritic grains in the oxide layer were different from those of coarse matrix ferritic grains beneath the oxide layer;however,some ferritic grains exhibited same orientations as those in the neighboring *** nitrogen content was detected in the oxide layer than that in the matrix beneath the oxide *** form of nitrogen enrichment in the oxide layer was analyzed,and the growth mechanism of ferritic grains during the oxide layer formation is proposed.

关键词： grain-oriented silicon steel decarburization annealing oxide layer ferritic grains silica

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Phase Separation and Crystallization Induced by Electron Irradiation in Nanoscale Fe_(56.5)Mn_(11)Cr_(8.5)Ni_4Si_(10)C_(10) Metallic Glass

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Acta Metallurgica Sinica(English Letters) 2015年第11期28卷 1332-1335页

作者： xiao-yang Chen Shu-Guang Zhang Ming-Xu xia Jian-Guo Li School of Materials Science and Engineering Shanghai Jiao Tong University

A nanoscale Fe56.5Mn11Cr8.5Ni4Si10C10 metallic glass was irradiated by electron beam in a 200 kV trans- mission electron microscope. Structure evolution in the metallic glass was investigated in situ during continuous irradi- ation, where phase separation was observed after irradiation for 5 min and crystallization was observed after 33.5 min. Based on the analysis of irradiation effect, atomic displacement is believed to be the main reason for the structure rearrangement. Accumulation of atomic displacement increases the energy of the sample and promotes atomic diffusion during transformation. On the other hand, the large specific surface area of the sample also contributes to increasing free energy and atomic diffusion.

关键词： Metallic glass Electron irradiation Transmission electron microscopy Phase separation Crystallization

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Improvement, Comparison, and Application of Field Measurement Methods for Grassland Vegetation Fractional Coverage

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Journal of Integrative Plant Biology 2005年第9期47卷 1074-1083页

作者： xiao-Bing LI Yun-Hao CHEN Hua yang Yun-xia ZHANG College of Resources Sciences and Technology Key Laboratory of Environmental Change and Natural Disaster of the Ministry of Education Beijing Normal University Beijing 100875 China

As one of the important vegetation parameters, vegetation fractional coverage （VFC） is more difficult to measure accurately among a good many parameters of plant communities. The temperate typical steppe in the north of China was chosen for investigation in the present study and a digital camera was used to measure herb community coverage in the field, adopting methods of ocular estimation, gridding measurement, visual interpretation, supervised classification, and information extraction of color spatial transformation to calculate the VFC of images captured by the digital camera. In addition VFC calculated by various methods was analyzed and compared VFC, enabling us to propose an effective method for measuring VFC using a digital camera. The results of the present study indicate that：（i） as two common useful and effective methods of measuring VFC with a digital camera, not only does the error of estimated values of visual estimation and supervised classification vary considerably, but the degree of automatization is very low and depends, to a great extent, on the manipulator; （ii） although the method of visual interpretation may assure the precision of the calculated VFC and enable the precision of results obtained using other methods to be determined, as far as large quantities of data are concerned, this method has the disadvantages of wasting time and energy, and the applications of this method are limited; （iii） the precision and stability of VFC calculated using the grid and node method are superior to those of visual estimation and supervised classification and inferior to those of visual interpretation, but, as for visual interpretation and supervised classification, gridding measurements are difficult to apply in practice because they are not time efficient; and （iv） in terms of the precision of calculation of the VFC, an information-extracting model based on an intensity, hue, saturation （IHS） color space-multi-component series segmentation strategy is s

关键词： color space transformation digital camera field measurement grassland vegetationfractional coverage.

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Corrosion Fatigue Behavior of 7A85 Aluminum Alloy Thick Plate in NaCl Solution

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Acta Metallurgica Sinica(English Letters) 2015年第8期28卷 1047-1054页

作者： Zuo-Yan Ye Dao-Xin Liu xiao-Hua Zhang xiao-Ming Zhang Ming-xia Lei Zhi yang Corrosion and Protection Research Laboratory Northwestern Polytechnical University AVIC the First Aircraft Institute

The S–N curves of 7A85-T7452 aluminum alloy in laboratory air and in neutral 3.5 wt% NaCl solution were obtained by axial fatigue tests. Results show that the detrimental effect of the aggressive solution was not noticeable at high-cyclic-stress regions, but the effect was significant at low-stress region. Corrosion fatigue mechanism was discussed by corrosion morphology analysis, fracture surface analysis and microstructure characterization. It was found that the corrosion fatigue crack commonly initialed at the localized intergranular corrosion site. TEM analysis showed that the microstructures of 7A85-T7452 aluminum alloy were characterized by fine and homogeneously distributed matrix precipitates, as well as continually distributed anodic grain boundary precipitates. The types of microstructures are the reason for its intergranular corrosion susceptibility. The corrosion fatigue process of 7A85 aluminum alloy in 3.5 wt% NaCl solution can be divided into four stages： the crack initiation stage, the stable growth stage with low and high growth rate and the final rupture stage. The sodium chloride solution mainly affected the crack initiation stage and the stable growth stage with low growth rate, and when the crack growth rate reached a threshold, the effect was reduced.

关键词： Corrosion fatigue Intergranular corrosion Microstructure 7A85 aluminum alloy

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Defective callose walls and cell plates during abnormal meiosis cause male-sterility in the oat mutant zbs1

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Journal of Integrative Agriculture 2016年第2期15卷 241-248页

作者： SHI xiao WU Jin-xia ZHOU Hai-tao yang xiao-hong LI Tian-liang ZHANG Xin-jun yang Cai HAN xiao Biotechnology Research Institute Chinese Academy of Agricultural Sciences/National Key Facility for Gene Resources and Gene Improvement Beijing 100081 P.R.China Zhangjiakou Academy of Agricultural Sciences Zhangjiakou 075000 P.R.China

During meiosis in flowering plants,degradation of the callose wall in tetrads releases newly produced microspores,which develop into mature pollen *** this study,we identified zbs1,a male-sterile mutant of naked oat（Avena nuda L.）that displayed complete spikelet sterility due to inviable mature *** abnormal pollen grains originated from microspores with a defective callose wall and cell plate during *** defective callose wall and cell plate of the zbs1 mutant were detected by the labeling of cell wall epitopes（β-1,3-glucan） with immunogold during meiosis,and an abnormal chromosome configuration was observed by propidium iodide *** mature pollen grains of the zbs1 mutant were irregular in shape,and abnormal germination was observed by scanning electron ***,our results indicate that the cause of male sterility in zbs1 is abnormal meiosis.

关键词： callose male sterility meiosis microspore naked oat

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Towards understanding the microstructure and temperature rule in large strain extrusion machining

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Advances in Manufacturing 2021年第2期9卷 262-272页

作者： Yun-Yun Pi Wen-Jun Deng Jia-yang Zhang xiao-Long Yin Wei xia College of Mechanical and Automobile Engineering South China University of TechnologyGuangzhou 510640People’s Republic of China

Large strain extrusion machining(LSEM)is a typical process for preparing ultrafine or nanocrystalline *** based on large plastic *** processing parameters of LSEM in this study were optimized by experiments and *** the orthogonal array,signal-to-noise ratio,and analysis of variance,the influence and contribution of processing parameters on response variables were *** of the difference in processing parameters between optimizing the average grain size and the maximum temperature,the response variables analyzed must be correctly ***,the optimal processing parameters for obtaining the minimum average grain size and the lowest maximum temperature are *** results show that the tool rake angle is the most important ***,the level of this factor required to achieve the minimum average grain size is different from that required to obtain the lowest maximum *** validity of the method is verified through experiments and simulations.

关键词： Large strain extrusion machining(LSEM) Taguchi design Analysis of variance(ANOVA) Average grain size Maximum temperature

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Geochemistry and Geochronology of the Cenozoic Zhalaga Granitoids of the Yulong Alkali-rich Porphyry Belt in Eastern Tibet(Xizang), SW China: Petrogenesis and Tectonic Implications

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Acta Geologica Sinica(English Edition) 2020年第6期94卷 2077-2090页

作者： XU Chi YUAN Yajuan xiao yang GUO Feng xia Bin LU Ye School of Marine Sciences Sun Yat-sen UniversityGuangzhou 510006China Key Laboratory of Offshore Oil Exploration and Development of Guangdong Higher Education Institutes Guangzhou 51006China Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering Guangzhou 510006China School of Geography South China Normal UniversityGuangzhou 510631China Guangdong Marine Geological Survey Institute Guangzhou 510075China

Large-scale Cenozoic magmatic rocks from the interplay between the Indian and Eurasian plate are exposed in the Yulong porphyry copper belt in the northern Jinshajiang-Ailaoshan ***-rich magmas along the Yulong porphyry copper belt can reveal the tectono-magmatic processes in the Sanjiang *** this study,we present new zircon U-Pb-Hf isotopes and whole rock geochemistry of Cenozoic granitoids from the Zhalaga area in the northern Yulong porphyry copper *** Zircon U-Pb dating results show that the Zhalaga granitic porphyry crystallized at ca.42-38 *** porphyry deposits are depleted in Nb,Ta,Sr,and Ti enriched in alkaline and rare earth elements(REEs),and exhibit high zircon saturation temperatures,that strongly indicate A-type *** data and the generally positiveεHf(t)values(2.0-4.5)suggest the magmas originated from a hybrid of partial melting of subduction-modified lithospheric mantle,possibly triggered by upwelling of the asthenospheric *** and geochemical data of the current and previous studies distinguish three magmatic phases during the Cenozoic in the Jinshajiang-Ailaoshan region:(1)ca.62-48 Ma;(2)ca.44-30 Ma;and(3)ca.28-16 *** strong collision between the Indian and Eurasian plates produced relatively fast convergence rates during the first episode(ca.62-48 Ma),whereas the subsequent right-lateral strike-slip faulting in the Jinshajiang fault zone initiated at ca.43 Ma is associated with the relatively low India-Eurasia convergence rates during ca.44-30 *** significantly impacted the nature and spatial distribution of the magmatism and the large-scale metallogeny during the Cenozoic in the Sanjiang *** suggest that the Zhalaga alkali-rich magmas occurred in a transition period from involving soft to hard collisional *** remarkable example demonstrates that alkali-rich magmas with A-type affinity are also generated in an orogenic tectonic setting.

关键词： alkali-rich magmas A-type granite Jinshajiang-Ailoashan domain

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盐酸米诺环素治疗牙周牙髓联合病变的疗效及对CRP、TNF-α的影响

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局解手术学杂志 2018年第8期27卷 593-596页

作者：粟宾彬李娜夏晓杨喻锦娴龚博林武汉市中医医院口腔科湖北武汉430014 湖北省中西医结合医院口腔科湖北武汉430015 武汉第一口腔医院湖北武汉430079

目的探究盐酸米诺环素对于牙周-牙髓联合病变的治疗效果,以及其对血清龈沟液内容物C-反应蛋白(CRP)和肿瘤坏死因子α(TNF-α)的影响。方法选择2015年2月至2016年2月武汉市中医医院口腔科治疗的58例牙周-牙髓联合病变患者,随机分为治疗组... 详细信息

目的探究盐酸米诺环素对于牙周-牙髓联合病变的治疗效果,以及其对血清龈沟液内容物C-反应蛋白(CRP)和肿瘤坏死因子α(TNF-α)的影响。方法选择2015年2月至2016年2月武汉市中医医院口腔科治疗的58例牙周-牙髓联合病变患者,随机分为治疗组(29例)和对照组(29例),对照组采用常规根管治疗、刮治术和根面平整术治疗,治疗组在对照组的基础上给予盐酸米诺环素局部用药,于治疗前和治疗后4周对静脉血和龈沟液取样,检测样本中CRP和TNF-α含量。结果治疗组患者血清和龈沟液中CRP和TNF-α含量低于对照组,多项牙周诊查指标也优于对照组。结论盐酸米诺环素辅助刮治术和根平整术对于牙周-牙髓联合病变有较好疗效,优于传统常规治疗手段。

关键词：盐酸米诺环素牙周-牙髓 C-反应蛋白肿瘤坏死因子α

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