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Corneal stem cells and tissue engineering: Current advances and future perspectives

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World Journal of Stem Cells 2015年第5期7卷 806-814页

作者： Aline lütz de Araujo JoséAlvaro pereira Gomes Clínica lentecor Porto Alegre-RS 90570041Brazil Department of Ophthalmology and Visual Sciences Universidade Federal de São PauloSao Paulo-SP 04023062Brazil

Major advances are currently being made in regenerative medicine for cornea. Stem cell-based therapies represent a novel strategy that may substitute conventional corneal transplantation, albeit there aremany challenges ahead given the singularities of each cellular layer of the cornea. This review recapitulates the current data on corneal epithelial stem cells, corneal stromal stem cells and corneal endothelial cell progenitors. Corneal limbal autografts containing epithelial stem cells have been transplanted in humans for more than 20 years with great successful rates, and researchers now focus on ex vivo cultures and other cell lineages to transplant to the ocular surface. A small population of cells in the corneal endothelium was recently reported to have self-renewal capacity, although they do not proliferate in vivo. Two main obstacles have hindered endothelial cell transplantation to date: culture protocols and cell delivery methods to the posterior cornea in vivo. Human corneal stromal stem cells have been identified shortly after the recognition of precursors of endothelial cells. Stromal stem cells may have the potential to provide a direct cell-based therapeutic approach when injected to corneal scars. Furthermore, they exhibit the ability to deposit organized connective tissue in vitro and may be useful in corneal stroma engineering in the future. Recent advances and future perspectives in the field are discussed.

关键词： Cornea Stem cells Cell-based therapy limbal transplantation Tissue engineering Cornealendothelium

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气象数据缺测条件下参照腾发量的计算方法

水利学报 2001年第3期32卷 11-17页

作者：刘钰 l.S.pereira 中国水利水电科学研究院水利所北京100044 葡萄牙里斯本技术大学农学院农业工程系

利用河北雄县和望都两气象站的数据 ,对FAO推荐的气象数据缺测时参照腾发量的计算方法进行了检验和评价 ,分析了参照腾发量对各气象要素的敏感性。

关键词：参照腾发量彭曼-蒙特斯方程气象数据农作物

Discrepancies between clinical and autopsy findings in patients who had an acute stroke

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Stroke & Vascular Neurology 2022年第3期7卷 215-221页

作者： lilla Hudák Attila Csaba Nagy Sarolta Molnár Gábor Méhes Katalin Erzsébet Nagy lászlóoláh lászlóCsiba Department of Neurology University of Debrecen Faculty of MedicineDebrecenHungary Department of Preventive Medicine University of Debrecen Faculty of Public HealthDebrecenHungary Department of Pathology University of Debrecen Clinical CenterDebrecenHungary Doctoral School of Neuroscience University of Debrecen Faculty of MedicineDebrecenHungary

Objectives According to international observations,the incidence of clinical autopsies is declining worldwide,plummeting below 5%in the USA and many European *** is an unfavourable trend as,in 7%-12%of cases,recent clinicopathological studies found discrepancies that might have changed the therapy or the outcome if known *** previous large-scale observations have examined varied patient populations,we aimed to focus on the differences between the clinical and pathological diagnostic findings in only patients who had a *** and methods We assessed the postmortem non-neuropathological and neuropathological findings of 534 consecutive patients who had a stroke who passed *** neoplasms,pneumonias,thromboembolisms and haemorrhagic transformations revealed only by autopsy were considered severe abnormalities;in addition,benign abnormalities important from an educational or scientific point of view were also *** In 26 of the 534 cases(4.9%),the presence of systemic neoplasms had already been confirmed in the clinical stage;however,8(1.5%)malignant tumours were only detected during ***,80(15%)thromboembolic events,73(13.6%)pneumonias and 66(18%)haemorrhagic transformations were only diagnosed at *** hospital stay(from admission to death)resulted in fewer discrepancies between clinical and autopsy diagnosis of thromboembolic events and pneumonias(ple the type of acute stroke is reliably diagnosed with imaging techniques,postmortem autopsies are also important in patients who had a stroke as autopsies may reveal clinically silent diseases(eg,tumour),and contribute to knowing the actual incidence of stroke-related thromboembolic and pneumonia complications.

关键词： neoplasms clinical finding

Cyto-protective Effects of Extracts of Panax Quinquefolius

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Cyto-protective Effects of Extracts of Panax Quinquefolius

Highly electroactive N–Fe hydrothermal carbons and carbon nanotubes for the oxygen reduction reaction

第十四届全国中药和天然药物学术研讨会

作者： EMK lui l.pereira J.Ma Q Zhang T.Fatima S.lee I Welch Ontario Ginseng Innovation Research Consortium Western University

＜正＞Ginseng is known to have anti-oxidative anti-inflammatory *** our study we have examined extracts derived from Ontario grown Panax quinquefolius for its cyto-protective and immunomodulatory effects in two experi...

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Journal of Energy Chemistry 2020年第11期29卷 260-270页

作者： R.G.Morais N.Rey-Raap J.l.Figueiredo M.F.R.pereira Associate laboratory lSRE-lCM Departamento de Engenharia QuimicaFaculdade de EngenhariaUniversidade do PortoR.Dr.Roberto Frias s/n4200-465PortoPortugal

Glucose-derived carbons were prepared by hydrothermal carbonization of glucose followed by carbonization or activation to obtain carbon materials with different microporosities. These microporous carbons and carbon nanotubes(CNTs) were functionalized with melamine and/or iron(Ⅱ) phthalocyanine(FePc)following three different methodologies:(i) Functionalization with melamine via thermal treatment,(ii)incorporation of the lowest amount of FePc reported in the literature via incipient wetness impregnation followed by thermal treatment and(iii) functionalization with melamine followed by Fe Pc *** chemical and textural characterization of the prepared materials and their electrochemical assessment allowed to understand the role of microporosity in the incorporation of FePc and its effect on the oxygen reduction reaction(ORR). It was observed that FePc was preferentially incorporated inside the porous structure, especially in samples with more developed microporosity. However, functionalization with melamine modified the textural properties and the surface chemistry, favoring the incorporation of FePc on the surface. Regarding the electrochemical performance, the presence of FePc greatly enhanced the electroactivity of the microporous catalysts. An onset potential of 0.88 V and a four-electron pathway were obtained for glucose-derived carbons, whereas the limiting current densities and kinetic current densities rose by 126% and 222%, respectively, in comparison to the base sample. Notwithstanding, the highest electrochemical activity was observed for the sample prepared with CNTs, due to the synergy between the active metal centers and their highly graphitic carbon structure. The electrochemical parameters of CNTFeP csurpass the commercial Pt/C. The half-wave potential is 40 mV higher, the limiting current density increases by 17%, and a negligible production of by-products(< 1%) was observed.

关键词： Iron(Ⅱ)phthalocyanine Hydrothermal carbons Carbon nanotubes Oxygen reduction reaction Electrocatalysis

Pulp and Paper from Sugarcane:Properties of Rind and Core Fractions

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Journal of Renewable Materials 2018年第2期6卷 160-168页

作者： lísias pereira Novo Julien Bras Mohamed Naceur Belgacem Antonio Aprigio da Silva Curvelo Department of Materials Engineering Sao Carlos School of EngineeringUniversity of Sao PauloAv.Joao Dagnone 110013563-120Sao CarlosSao PauloBrazil Department of Physical Chemistry Sao Carlos Institute of ChemistryUniversity of Sao PauloAv.Trabalhador Sao Carlense 40013560-970Sao CarlosSao PauloBrazil Grenoble Alpes University LGP2F-38000 GrenobleFrance CNRS LGP2F-38000 GrenobleFrance

Two distinct lignocellulosic fractions(rind and core)can be obtained through a physical separation of sugarcane *** presenting differences in morphology,both fractions can be employed to produce pulps and *** pulps and paper sheets produced from the core and rind fractions were characterized by their chemical composition,physical properties and mechanical *** pulps obtained from the core presented a higher amount of fines,lower drainage ability and rendered denser and stiffer *** pulps from the rind,which have a higher content of fibers and higher degree of polymerization,produced sheets with higher air permeability and water *** paper sheets presented mechanical and physical properties comparable to commercial papers and papers from different cellulosic *** different properties exhibited by the papers produced from each fraction allow their use for distinct purposes,and expands the opportunities in the context of sugarcane biorefinery.

关键词： Sugarcane core and rind fractions papermaking pulp and paper

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考虑地面灌水技术制约的灌溉制度优化

农业工程学报 2003年第4期19卷 74-79页

作者：刘钰 l.S.pereira 中国水利水电科学研究院水利研究所北京100044 葡萄牙里斯本技术大学高等农学院农业工程系

制定作物灌溉制度不仅要考虑补充根层土壤水分以满足作物需求 ,还应考虑灌水方法对灌水量的限制。为研究我国华北地区地面灌溉条件下冬小麦 -夏玉米连作的节水灌溉制度 ,在河北省雄县进行了连续 3年不同灌水处理试验 ,用水量平衡模型 IS... 详细信息

制定作物灌溉制度不仅要考虑补充根层土壤水分以满足作物需求 ,还应考虑灌水方法对灌水量的限制。为研究我国华北地区地面灌溉条件下冬小麦 -夏玉米连作的节水灌溉制度 ,在河北省雄县进行了连续 3年不同灌水处理试验 ,用水量平衡模型 ISAREG对各处理进行数值模拟 ,从而验证了选定的模型和参数。采用该模型模拟了不同水文年冬小麦 -夏玉米连作的多种灌溉制度 ,对各方案的灌水次数、灌水量、降雨和灌溉水量损失以及作物产量等因素进行了对比 ,并对现行灌溉制度进行了评价。结果显示 :雄县现行灌溉定额大大超过了灌溉需水量 ,主要原因是地面灌水技术的制约 ,如田面不平、进地流量过小或畦块过大等 ,造成难以控制小水量灌溉。为研究既能满足作物基本需水要求 ,又使灌溉水量损失最小的最佳灌水定额 ,用模拟地面灌溉水流运动的 SRFR模型模拟不同生长阶段的灌溉 ,得到了每次灌溉时不同流量条件下的最小灌水量 ,以及灌水效率与灌水量的关系 ,据此提出了与灌水技术改进措施相结合的不同水文年的灌溉制度优化方案。

关键词：地面灌水技术灌溉制度模型验证方案选择

Effective and simple recovery of 1,3-propanediol from a fermented medium by liquid–liquid extraction system with ethanol and K_3PO_4

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Chinese Journal of Chemical Engineering 2018年第1期26卷 104-108页

作者： Daiana Wischral Hongxin Fu Fernando l.Pellegrini Pessoa Nei pereira Jr Shang-Tian Yang School of Chemistry Department of Biochemical EngineeringFederal University of Rio de Janeiro William G.lowrie Department of Chemical and Biomolecular Engineering The Ohio State University School of Chemistry Department of Chemical EngineeringFederal University of Rio de Janeiro

1,3-Propanediol,traditionally obtained from fossils,has numerous industrial applications,including use in the production of high performance *** microbial production of 1,3-propanediol presents several opportunities,and the final purity grade determines its price and commercial *** development of novel separation technology could improve the economic viability of the bioproduction of 1,***,we investigated salting-out extraction as a novel process for 1,3-propanediol recovery from fermentation ***,a screening for the best salt/solvent combination was conducted and then optimized using the response surface *** solvents studied were methanol,ethanol,isopropanol and acetone,and the salts examined were K_2HPO_4,Na_2CO_3,K_2CO_3,(NH_4)_2SO_4,NaHPO_4,K_3PO_4 and C_6H_5NaO_*** optimal extraction system consisted of 34 wt%K_3PO_4,28 wt% ethanol,and 38 wt% fermentation broth containing 23.0 g·l^(-1)1,3-propanediol,which gave the highest partition coefficient of 33 and recovery yield of 97%.The results demonstrated that salting-out extraction was a promising method for 1,3-propanediol recovery from fermentation broth.

关键词： Fermentation Downstream process 1 3-Propanediol Clostridium beijerinckii liquid-liquid extraction Salting-out extraction

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