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Rilmenidine prevents blood pressure increase in rats with compromised nitric oxide production

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Acta Pharmacologica Sinica 2004年第12期25卷 74-80页

作者： mria GEROV,Jozef TRK,Ol’ga PECHV,Jana mATUKOV Institute ofNormal and Pathological Physiology SlovakAcademy of Sciences 813 71 Bratislava Slovak Republic Institute ofNormal and Pathological Physiology SlovakAcademy of Sciences 813 71 Bratislava Slovak Republic Institute ofNormal and Pathological Physiology SlovakAcademy of Sciences 813 71 Bratislava Slovak Republic Institute of Pathophysiology medical School Comenius University Bratislava Slovak Republic Now in Center for Blood Research and Department of Pathology Harvard medicalSchool Boston USA.

AIm: To search tools of high blood pressure in the model of nitric oxide (NO)-defective hypertension, and the study focused on the effect of rilmenidine, agonist of imidazoline receptors, which was suggested to modulate central sympathetic outflow. mETHODS: Three experimental groups, each consisting of 7 rats, were used: (I) rats with inhibition of NO synthase (NOS) by NG-nitro-L-arginine methyl ester (L-NAmE) 40 mg·kg-1·d-1 for 4 weeks in drinking water, (II) rats with inhibited NOS as in group I , plus agonist of imidazoline receptors rilmenidine 3 mg·kg-1·d-1 for 4weeks by gavage, and(III) control rats. Systolic blood pressure wasmeasured weekly noninvasively. At the end of experiment aortic ring isometric tension was followed, NOS expression (aorta, left ventricle), and NOS activity (left ventricle and brain) were determined. RESULTS: In the group I systolic blood pressure in- creased significantly, aortic ring relaxation to acetylcholine was significantly attenuated. Rilmenidine administered simultaneously with L-NAmE (group II) prevented the increase of blood pressure which did not differ significantly from control values; aortic ring relaxation to acetylcholine did not differ from control. No change in NOS expres- sion (aorta and left ventricle) was found in groups I and II. Significant decline in NOS activity (left ventricle and brain) wasfound in groups I and II. CONCLUSION: Rilmenidinehas aremarkable role inNO-defective hypertension, possibly by inhibiting central sympathetic outflow and by affecting receptors in vascular smooth muscle also. The prime cause of hypertension in this experimental model - the compromised production of NO due to inhibition of NOS - was not affected by rilmenidine.

关键词： NO deficiency hypertension imidazoline receptor nitric-oxide synthase sympathetic activity

利用集合均方根卡尔曼滤波反演重庆地区SO_2源排放

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环境科学研究 2018年第1期31卷 25-33页

作者：吴钲谢旻高阳华芦华赵磊高松重庆市气象科学研究所重庆401147 南京大学江苏南京210093

传统的"自下而上"清单方法估算的排放清单,其数据的准确性和时效性存在较大局限.基于集合均方根卡尔曼滤波的源清单反演方法,结合WRF-CmAQ(天气研究和预报模式-公共多尺度空气质量模型)被用于对以清华大学编制的2010年mEIC(中国多尺度... 详细信息

传统的"自下而上"清单方法估算的排放清单,其数据的准确性和时效性存在较大局限.基于集合均方根卡尔曼滤波的源清单反演方法,结合WRF-CmAQ(天气研究和预报模式-公共多尺度空气质量模型)被用于对以清华大学编制的2010年mEIC(中国多尺度排放清单模型)排放清单为基础制作的重庆地区SO_2排放源进行反演试验以解决准确性和时效性问题,试验时间段为2014年10月15—31日,重庆主城17个环境空气质量国控监测点ρ(SO_2)小时观测资料用于反演及检验.结果表明:该方法能够反演重庆地区SO_2源排放量,随着反演次数增加,基于反演排放源预报的ρ(SO_2)预报误差持续减小,反演4次后预报误差达到比较低的稳定的水平,其均方根误差均低于20μg/m^3.5次反演后SO_2源排放量用于2014年10月24—29日每天起始预报,其预报的站点、时间平均的均方根误差从100~400μg/m^3降至30μg/m^3以下.反演中应用局地化尺度减少集合取样误差影响,54与81 km两个局地化尺度反演结果对预报改善效果相当,表明主要影响重庆主城ρ(SO_2)的源排放位于主城及周边地区,也说明内源排放对重庆主城ρ(SO_2)起主要影响.反演后面源排放量主城区降幅约为30 kg/(d·km^2),周边地区减少10~20 kg/(d·km^2),主城区部分SO_2点源排放量降幅约为25 kg/(d·km^2),说明2010年mEIC排放清单高估了试验时段重庆地区的SO_2排放.

关键词： S02 WRF-CmAQ 源排放反演集合均方根卡尔曼滤波

Targeting harmful effects of non-excitatory amino acids as an alternative therapeutic strategy to reduce ischemic damage

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Neural Regeneration Research 2025年第9期20卷 2454-2463页

作者： Victoria Jiménez Carretero IrisÁlvarez-merz Jorge Hernández-Campano Sergei A.Kirov Jesús m.Hernández-Guijo Department of Pharmacology and Therapeutic School of MedicineUniv.Autónoma de MadridMadridSpain Ramón y Cajal Institute for Health Research(IRYCIS) Neurobiology-Research ServiceHospital Ramón y CajalMadridSpain Institute of Neurobiology Faculty of Mathematics and Natural SciencesHeinrich Heine University DüsseldorfDüsseldorfGermany Department of Neuroscience and Regenerative medicine&Department of Neurosurgery Medical College of Georgia at Augusta UniversityAugustaGAUSA

The involvement of the excitatory amino acids glutamate and aspartate in ce rebral ischemia and excitotoxicity is ***,the role of non-excitatory amino acids in brain damage following a stroke or brain trauma remains largely *** release of amino acids by necrotic cells in the ischemic core may contribute to the expansion of the *** findings indicated that the reversible loss of field excitato ry postsynaptic potentials caused by transient hypoxia became irreversible when exposed to a mixture of just four non-excitatory amino acids(L-alanine,glycine,L-glutamine,and L-serine)at their plasma *** amino acids induce swelling in the somas of neurons and astrocytes during hypoxia,along with permanent dendritic damage mediated by N-methyl-D-aspartate *** N-methyl-D-aspartate receptors prevented neuronal damage in the presence of these amino acids during *** is likely that astroglial swelling caused by the accumulation of these amino acids via the alanine-serine-cysteine transporter 2 exchanger and system N transporters activates volume-regulated anion channels,leading to the release of excitotoxins and subsequent neuronal damage through N-methyl-D-aspartate receptor ***,previously unrecognized mechanisms involving non-excitatory amino acids may contribute to the progression and expansion of brain injury in neurological emergencies such as stroke and traumatic brain *** these pathways co uld highlight new therapeutic targets to mitigate brain injury.

关键词： cell swelling N-methyl-D-aspartate receptor non-excitatory amino acids stroke synaptic transmission

Tribological properties of polyimide composites reinforced with fibers rubbing against Al_(2)O_(3)

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Friction 2021年第2期9卷 301-314页

作者： Huimin QI ga ZHANG Zhiqin ZHENG Jiaxin YU Chao HU Key Laboratory of Testing Technology for manufacturing Process in ministry of Education State Key Laboratory of Environment-friendly Energy MaterialsSouthwest University of Science and TechnologyMianyang 621010China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Qingdao Center of Resource Chemistry&New materials Qingdao 266071China Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory Southwest University of Science and TechnologyMianyang 621010China

Reinforcing fillers are of great importance in tribological performance and tribofilm formation of polymeric *** this study,the tribological properties of aramid particle(AP)and short carbon fiber(SCF)reinforced polyimide(PI)composites were added to hexagonal boron nitride(h-BN),and silica(SiO_(2))nanoparticles sliding against alumina were comprehensively *** sliding occurred with AP-reinforced PI composites,the tribological properties were not closely depended on the pressure×velocity(p×v)factors and the *** interactions between AP and its counterpart could not induce tribo-sintering of the transferred wear *** such,the tribofilm seemed to be in a viscous state,leading to higher friction and ***,the inclusion of hard SCF into the PI matrix changed the interfacial interactions with alumina.A robust tribofilm consisting of a high fraction of silica was generated when the SCF-reinforced PI was added to the SiO_(2) *** exhibited a high load-carrying capability and was easily *** caused a significant decrease in the friction and wear of the PI composite at 8 mPa·1m/***,due to their high melting point,few h-BN nanoparticles were observed in the tribofilm of the SCF-reinforced PI when hexagonal boron nitride was added.

关键词： reinforcing filler polyimide composite tribofilm Al_(2)O_(3)

Study on the bone marrow mesenchymal stem cells induced drug resistance in the U937 cells and its mechanism

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Chinese medical Journal 2006年第11期119卷 905-910页

作者： LIN Yu-mei ZHANG Gui-zhen LENG Zong-xiang LU Zhen-xia BU Li-sha ga0 Shen YANG Shao-juan Department of Hematology and Oncology China-Japan United Hospital of Jilin University Changchun 130031 China Central Laboratory China-Japan United Hospital of Jilin University Changchun 130031 China Department of Obstetrics and Gynecology China-Japan United Hospital of Jilin University Changchun 130031 China

Background The hematopoietic microenvironment （Hm） plays a critical role in malignant cell growth, patient survival, and response to chemotherapy in hematologic malignancies. However, mechanisms associated with this environmental influence remain unclear. In this study, we investigated the role of bone marrow derived mesenchymal stem cells （mSCs） in U937 cell line, the mSCs. to find out the relations between leukemia drug resistance and methods U937 cells were cultured in suspension or grew adherently with mSCs. The cell growth curve was drawn and the cell cycle was measured by flow cytometry. Apoptosis and sensitivity of U937 to daunoblastina （DNR） were quantified by DNA ladder detection and trypan blue exclusion assays, respectively. The gene expression profile chip technology was used to determine and analyze the changes in apoptosis-related gene expression after adherent culture and the expression of mDR 1 mRNA was assessed by reverse transcriptional polymerase chain reaction （RT-PCR） at the same time. Results In the adherent culture, the proliferation of the U937 cells was inhibited, the G0/G1 phase cells increased （F=64.9726, P〈0.0001）, G2/m phase cells were decreased （F=98.1361, P〈0.0001） and the natural apoptosis rate was decreased （F=24.0866, P〈0.0001） compared with those in the suspended culture. U937 cell viability was enhanced and cell apoptosis was blocked during DNR treatment in adherent culture with mSCs. Thirty-nine differently expressed genes were screened from the 487 apoptosis related genes in the adherent culture U937 cells. Among the 37 upregulated genes, Bcl-XL was upregulated most significantly. Two genes were downregulated. Adherent culture did not induce mDR1 mRNA expression in U937 cells. Conclusions mSCs play a role in modulating the proliferation of U937 cells and response of U937 cells to DNR, and Bcl-XL apoptosis-inhibiting gene may be most important in determining the sensitivity of leukemic cells to treatment, which is not related to

关键词： mesenchymal stem cells U937 cells drug resistance gene expression cDNA microarray

Trace elements and stable sulfur isotopes in plants of acid mine drainage area:Implications for revegetation of degraded land

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Journal of Environmental Sciences 2020年第8期32卷 128-136页

作者： Agnieszka gałuszka Zdzisław mmigaszewski Andrzej Pelc Andrzej Trembaczowski Sabina Doł˛egowska Artur michalik Geochemistry and the Environment Division Institute of ChemistryJan Kochanowski University7 Uniwersytecka St.25-406 KielcePoland mass Spectrometry Laboratory Institute of PhysicsMaria Curie-Skłodowska University1 Maria Curie-Skłodowska Sq.20-031 LublinPoland

The abundances of trace elements,a low pH of water and soil in areas impacted by the acid mine drainage(AmD)may cause an excessive uptake of potentially toxic elements and nutritional imbalances in ***-tolerant,native plants are used for revegetation of degraded mining *** established levels of selected trace elements and stable sulfur isotopes in the above-ground plant biomass collected in a mining area in south-central *** 2016,20 samples of the most common species were collected from sites with a different influence of acid mine drainage and analyzed for trace elements by the inductively coupled plasma mass spectrometry *** the basis of the results obtained in 2016,the most contaminated site was selected for a more detailed study,in which sulfur contents and stable sulfur isotope ratios were determined together with trace elements in 17 *** results confirmed that the plants native to the AmD area efficiently accumulated trace elements,especially As and rare earth *** showed the highest content of trace elements,but exhibited the lowest concentrations of sulfur accompanied by the highestδ34S *** has been shown for the first time that stable sulfur isotope composition of AmD plants in south-central Poland is significantly depleted in the 34S isotope showing an averageδ34 S value of–10.5‰in comparison with positiveδ34S values in local vegetation growing outside the AmD area and in local precipitation.

关键词： Trace elements Stable sulfur isotopes Pyrite oxidation Rare earth elements Plants

Hazards and Landscape Changes(Degradations) on Hungarian Karst mountains Due to Natural and Human Effects

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Journal of mountain Science 2013年第1期10卷 16-28页

作者： móga JNOS Kiss KLAUDIA Szabó mRIA Kériné Borsodi ANDREA Kéri ANDRS mari LSZLó Knáb móNIKA Iván VERONIKA Geography and Earth Science Institute Etvs Loránd University Biology Institute Etvs Loránd University

In order to study the karstological processes within the karst ecological system,the geohazards and degradation of karst landscapes on the karst areas of the Bakony mountains(Hungary),we investigated the abiotic elements of the environment,soil and cover deposits,erosion soil decay;the changes in the quantity and quality of karst waters:contamination at swallow holes,contamination of karst springs;and the biogenic factors:surface vegetation coverage by the corine land cover method,plant-ecological examinations,qualification of surface waters with the help of biological water *** recognized that the increasing human activities during the past few centuries have had significant impact on the investigated landscapes of karst areas because of their spatial *** the scope of our research we concluded that the landscape changes due to natural and human effects can vary strongly on the different karst *** differences can arise from the climatic and geomorphologic situation,the coverlayer's qualities,etc.,but primarily from the different utilization of the investigated karst areas(*** intensity,characteristics and territorial extension of utilization).On the spot investigation we detected traces of new and fast geomorphological processes(gully formation,landslides,collapses,new sinkhole development) and landforms(sinkholes,gullies,swallow holes),which are clear evidences of the effect of climatic changes.

关键词： Karst landscape Geological hazards Soil erosion Limestone mountain

Unveiling the lamellar structure of the human cornea over its full thickness using polarization-resolved SHG microscopy

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Light(Science & Applications) 2023年第9期12卷 1782-1794页

作者： Clothilde Raoux Anatole Chessel Pierre mahou gaël Latour marie-Claire Schanne-Klein Laboratory for Optics and Biosciences Ecole PolytechniqueCNRSINSERMInstitut Polytechnique de Paris91128 PalaiseauFrance UniversitéParis-Saclay 91190 Gif-sur-YvetteFrance

A key property of the human cornea is to maintain its curvature and consequently its refraction capability despite daily changes in intraocular *** is closely related to the multiscale structure of the corneal stroma,which consists of 1-3µm-thick stacked lamellae made of thin collagen ***,the distribution,size,and orientation of these lamellae along the depth of the cornea are poorly characterized up to *** this study,we use second harmonic generation(SHG)microscopy to visualize the collagen distribution over the full depth of 10 intact and unstained human corneas(500-600µm thick).We take advantage of the small coherence length in epi-detection to axially resolve the lamellae while maintaining the corneal physiological ***,as raw epi-detected SHG images are spatially homogenous because of the sub-wavelength size of stromal collagen fibrils,we use a polarimetric approach to measure the collagen orientation in every *** a careful validation of this approach,we show that the collagen lamellae(i)are mostly oriented along the inferior-superior axis in the anterior stroma and along the nasal-temporal axis in the posterior stroma,with a gradual shift in between and(ii)exhibit more disorder in the anterior *** results represent the first quantitative characterization of the lamellar structure of the human cornea continuously along its entire thickness with micrometric *** also shows the unique potential of P-SHG microscopy for imaging of collagen distribution in thick dense tissues.

关键词： structure curvature resolved

DECAY PROCESSES OF HIGH-FREQUENCY NONEQUILIBRIUm PHONONS IN PRASEODYmIUm-DOPED LASER CRYSTALS

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发光学报 1999年第2期 40-48页

作者： Wang Xiaojun a) Dennis W m b) Yen W m b) a) (Department of Physics & Astronomy, Georgia Southern University, Statesboro, ga 30460, USA) b) (Department of Physics and Astronomy, The University of Georgia, Athens, ga 3

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１ＩＮＴＲＯＤＵＣＴＩＯＮＩｎａｒｅａｌｃｒｙｓｔａｌｓｙｓｔｅｍ，ｔｈｅｌａｔｉｃｅｖｉｂｒａｔｉｏｎｓｗｉｌｎｏｔｂｅｔｈｅｅｉｇｅｎｓｔａｔｅｓｏｆｔｈｅｓｙｓ－ｔｅｍ，ｉ．ｅ．，ａｎｉｎｉｔｉａｌｙｍｏｎｏｃｈｒｏｍａｔｉｃｎｏｎｅｑｕｉｌｉ...

关键词： nonequilibrium phonons high frequency phonons lattice dynamics YAG YLF