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Molecular mechanisms of mesenchymal stem cell differentiation towards osteoblasts 被引量:33
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作者 maya Fakhry René Buchet +2 位作者 David Magne Eva Hamade Bassam Badran 《World Journal of Stem Cells》 SCIE CAS 2013年第4期136-148,共13页
Bone is a dynamic tissue that is constantly renewed by the coordinated action of two cell types, i.e., the bone-resorbing osteoclasts and the bone-forming osteoblasts. However, in some circumstances, bone regeneration... Bone is a dynamic tissue that is constantly renewed by the coordinated action of two cell types, i.e., the bone-resorbing osteoclasts and the bone-forming osteoblasts. However, in some circumstances, bone regeneration exceeds bone self repair capacities. This is notably often the case after bone fractures, osteolytic bone tumor surgery, or osteonecrosis. In this regard,bone tissue engineering with autologous or allogenic mesenchymal stem cells(MSCs) is been widely developed. MSCs can be isolated from bone marrow or other tissues such as adipose tissue or umbilical cord, and can be implanted in bone defects with or without prior amplification and stimulation. However, the outcome of most pre-clinical studies remains relatively disappointing. A better understanding of the successive steps and molecular mechanisms involved in MSC-osteoblastic differentiation appears to be crucial to optimize MSC-bone therapy. In this review, we first present the important growth factors that stimulate osteoblastogenesis. Then we review the main transcription factors that modulate osteoblast differentiation, and the microRNAs(miRs)that inhibit their expression. Finally, we also discuss articles dealing with the use of these factors and miRs in the development of new bone MSC therapy strategies. We particularly focus on the studies using human MSCs, since significant differences exist between osteoblast differentiation mechanisms in humans and mice for instance. 展开更多
关键词 MESENCHYMAL stem cells OSTEOGENESIS Runt-related 2 WNT MICRORNAS
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Mechanism of sperm capacitation and the acrosome reaction: role of protein kinases 被引量:18
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作者 Debby Ickowicz maya Finkelstein Haim Breitbart 《Asian Journal of Andrology》 SCIE CAS CSCD 2012年第6期816-821,共6页
Mammalian sperm must undergo a series of biochemical and physiological modifications, collectively called capacitation, in the female reproductive tract prior to the acrosome reaction (AR). The mechanisms of these m... Mammalian sperm must undergo a series of biochemical and physiological modifications, collectively called capacitation, in the female reproductive tract prior to the acrosome reaction (AR). The mechanisms of these modifications are not well characterized though protein kinases were shown to be involved in the regulation of intracellular Ca2+ during both capacitation and the AR. In the present review, we summarize some of the signaling events that are involved in capacitation. During the capacitation process, phosphatidyl-inositol-3-kinase (PI3K) is phosphorylated/activated via a protein kinase A (PKA)-dependent cascade, and downregulated by protein kinase C a (PKCa). PKCa is active at the beginning of capacitation, resulting in PI3K inactivation. During capacitation, PKCa as well as PP172 is degraded by a PKA-dependent mechanism, allowing the activation of PI3K. The activation of PKA during capacitation depends mainly on cyclic adenosine monophosphate (cAMP) produced by the bicarbonate-dependent soluble adenylyl cyclase. This activation of PKA leads to an increase in actin polymerization, an essential process for the development of hyperactivated motility, which is necessary for successful fertilization. Actin polymerization is mediated by PIP2 in two ways: first, PIP2 acts as a cofactor for phospholipase D (PLD) activation, and second, as a molecule that binds and inhibits actin-severing proteins such as gelsolin. Tyrosine phosphorylation of gelsolin during capacitation by Src family kinase (SFK) is also important for its inactivation. Prior to the AR, gelsolin is released from PIP2 and undergoes dephosphorylation/activation, resulting in fast F-actin depolymerization, leading to the AR. 展开更多
关键词 sperm capacitation acrosome reaction AR PKCΑ PI3K PKA GELSOLIN PIP2
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中国传统燃油汽车退出时间表研究 被引量:15
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作者 安锋 康利平 +3 位作者 秦兰芝 毛世越 王雯雯 maya Ben Dror 《国际石油经济》 2019年第5期1-8,共8页
基于国家汽车发展目标、节能与新能源汽车技术发展预测、出行及汽车需求趋势判断,确定传统燃油汽车退出的2050未来情景,提出传统燃油汽车退出的时间表。燃油车退出区域划分为4个层级,第Ⅰ、Ⅱ层级以功能性、限购限行及新能源汽车推广领... 基于国家汽车发展目标、节能与新能源汽车技术发展预测、出行及汽车需求趋势判断,确定传统燃油汽车退出的2050未来情景,提出传统燃油汽车退出的时间表。燃油车退出区域划分为4个层级,第Ⅰ、Ⅱ层级以功能性、限购限行及新能源汽车推广领先城市为主,第Ⅲ、Ⅳ层级则以区域为主,燃油车退出过程以点及面递进。中国传统燃油汽车退出存在不确定性。新能源汽车快速发展面临稀有金属资源供应短缺、电池回收利用率低、充电基础设施建设不足等主要问题。建议在法规层面明确传统燃油汽车退出的目标优先级;深入论证传统燃油汽车禁售时间表,建立联合工作机制;基于车型与使用场景分阶段、分区域由点及面逐步禁售与退出;地方根据自身条件评估申报,根据国家战略框架制定具体实施方案,鼓励中大型城市提前实施;评估退出方案对传统燃油汽车产业及产业链的影响,并提前引导;加快研究出台新能源汽车通行管理政策;制定存量燃油汽车退出引导政策,提升新能源汽车保有量占比。 展开更多
关键词 燃油车 退出时间表 不确定性 风险 政策
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山东省放射工作人员五年外周血细胞计数与细胞遗传指标比较分析 被引量:15
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作者 刘东仁 张琳 +4 位作者 刘玉龙 刘伟 马娅 牛菲 闵楠 《中国辐射卫生》 2018年第4期322-326,共5页
目的通过调查山东省放射工作人员血常规中白细胞、血红蛋白、血小板计数的平均值,外周血淋巴细胞染色体畸变率和微核率,掌握山东省放射工作人员职业健康现状,探讨低剂量电离辐射对放射工作人员健康的影响。方法采用整体随机抽样法,对201... 目的通过调查山东省放射工作人员血常规中白细胞、血红蛋白、血小板计数的平均值,外周血淋巴细胞染色体畸变率和微核率,掌握山东省放射工作人员职业健康现状,探讨低剂量电离辐射对放射工作人员健康的影响。方法采用整体随机抽样法,对2013年-2017年期间进行职业健康检查的1 2496名放射工作人员血常规中白细胞、血红蛋白、血小板计数的平均值、外周血淋巴细胞染色体畸变率和微核率进行分析。结果 2013年-2017年期间,山东省放射工作人员血常规中白细胞、血红蛋白、血小板计数的平均值及外周血染色体畸变率的年度差异有统计学意义,但未观察到规律性变化,而微核率有呈逐年降低趋势(χ~2=28. 000,P <0. 05)。不同工种间比较,影像诊断组和X射线工业应用组血常规中白细胞、血红蛋白、血小板计数的平均值差异较大,其中白细胞平均值以探伤组最高,影像组次之,放疗组最低;血红蛋白平均值以工业辐照组最高,牙科组最低;血小板平均值以工业测井组最高,工业探伤最低。外周血淋巴细胞染色体畸变率和微核率分别以工业探伤组和工业辐照组最高,且都以牙科组最低。随工龄的延长,放射工作人员白细胞和血红蛋白平均值略有升高趋势,血小板均值略有下降趋势。微核率除岗前组相对较低外,在岗工作人员微核率随工龄变化趋势不明显。不同工龄水平,染色体畸变率未有统计学意义(χ~2=0. 209,P> 0. 05)。结论长期低剂量电离辐射可使机体受到一定的辐射损伤,其中放疗、介入和工业应用领域的放射工作人员是放射防护宣传和监督的重点人群。 展开更多
关键词 放射工作人员 电离辐射 染色体畸变率 微核率
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Stress ulcer prophylaxis guidelines:Are they being implemented in Lebanese health care centers? 被引量:10
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作者 Abeer Zeitoun maya Zeineddine Hani Dimassi 《World Journal of Gastrointestinal Pharmacology and Therapeutics》 CAS 2011年第4期27-35,共9页
AIM:To evaluate the current practice of stress ulcer prophylaxis (SUP) in Lebanese Health care centers.METHODS:A multi-center prospective chart review study was conducted over 8 mo.A questionnaire was distributed to p... AIM:To evaluate the current practice of stress ulcer prophylaxis (SUP) in Lebanese Health care centers.METHODS:A multi-center prospective chart review study was conducted over 8 mo.A questionnaire was distributed to pharmacy students who collected data on demographics,SUP medications,dose,route,duration and associated risk factors.The appropriateness of SUP use was determined as per American Society of Health-System Pharmacists guidelines.Institutional review board approval was obtained from each hospital center.RESULTS:A total of 1004 patients were included.67% of the patients who received prophylaxis did not have an indication for SUP.The majority (71.6%) of the patients who were administered parenteral drugs can tolerate oral medications.Overall,the regimen of acid-suppressant drugs was suboptimal in 87.6% of the sample.This misuse was mainly observed in non-teaching hospitals.CONCLUSION:This study highlighted the need,in Lebanese hospitals,to establish clinical practice guidelines for the use of SUP;mainly in non-critical care settings. 展开更多
关键词 Stress ulcer PROPHYLAXIS LEBANESE hospitals Proton-pump inhibitors HISTAMINE 2 receptor antagonists American Society of Health-System PHARMACISTS GUIDELINES
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Short-type single balloon enteroscope for endoscopic retrograde cholangiopancreatography with altered gastrointestinal anatomy 被引量:10
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作者 Hiroshi Yamauchi Mitsuhiro Kida +7 位作者 Kosuke Okuwaki Shiro Miyazawa Tomohisa Iwai Miyoko Takezawa Hidehiko Kikuchi maya Watanabe Hiroshi Imaizumi Wasaburo Koizumi 《World Journal of Gastroenterology》 SCIE CAS 2013年第11期1728-1735,共8页
AIM:To evaluate the effectiveness of a short-type single-balloon-enteroscope(SBE) for endoscopic retrograde cholangiopancreatography(ERCP) in patients with a reconstructed intestine.METHODS:Short-type SBE was develope... AIM:To evaluate the effectiveness of a short-type single-balloon-enteroscope(SBE) for endoscopic retrograde cholangiopancreatography(ERCP) in patients with a reconstructed intestine.METHODS:Short-type SBE was developed to perform ERCP in postoperative patients with a reconstructed intestine.Short-type SBE is a direct-viewing endoscope with the following specifications:working length,1520 mm;total length,1840 mm;channel diameter,3.2 mm.In addition,short-type SBE has a water-jet channel.The study group comprised 22 patients who underwent 31 sessions of short-type SBE-assisted ERCP from June 2011 through May 2012.Reconstruction was performed by Billroth-Ⅱ(B-Ⅱ) gastrectomy in 6 patients(8 sessions),Roux-en-Y(R-Y) gastrectomy in 14 patients(21 sessions),and R-Y hepaticojejunostomy in 2 patients(2 sessions).We retrospectively studied the rate of reaching the blind end(papilla of Vater or choledochojejunal anastomosis),mean time required to reach the blind end,diagnostic success rate(defined as the rate of successfully imaging the bile and pancreatic ducts),therapeutic success rate(defined as the rate of successfully completing endoscopic treatment),mean procedure time,and complications.RESULTS:Among the 31 sessions of ERCP,the rate of reaching the blind end was 88% in B-Ⅱ gastrectomy,91% in R-Y gastrectomy,and 100% in R-Y hepaticojejunostomy.The mean time required to reach the papilla was 18.3 min in B-Ⅱ gastrectomy,21.1 min in R-Y gastrectomy,and 32.5 min in R-Y hepaticojejunostomy.The diagnostic success rates in all patients and those with an intact papilla were respectively 86% and 86% in B-Ⅱ gastrectomy,90% and 87% in R-Y gastrectomy,and 100% in R-Y hepaticojejunostomy.The therapeutic success rates in all patients and those with an intact papilla were respectively 100% and 100% in B-Ⅱ gastrectomy,94% and 92% in R-Y gastrectomy,and 100% in R-Y hepaticojejunostomy.Because the channel diameter was 3.2 mm,stone extraction could be performed with a wire-guided basket in 12 sessions,and wireguided intraductal 展开更多
关键词 Endoscopic RETROGRADE CHOLANGIOPANCREATOGRAPHY Single-balloon-enteroscope Short type BillrothII GASTRECTOMY ROUX-EN-Y GASTRECTOMY
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基于EDEM的连续性立式搅拌机混合特性研究 被引量:10
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作者 毛娅 范雄 江智 《计算机仿真》 北大核心 2018年第12期181-184,415,共5页
为了研究颗粒物料在连续性立式搅拌机中的混合特性,以粉煤灰和污泥颗粒物料为例,利用EDEM仿真软件对连续性物料的混合过程进行了模拟。首先分析了搅拌机内物料的混合机理;建立了相应的搅拌机模型和颗粒接触模型,最后对比了不同搅拌转速... 为了研究颗粒物料在连续性立式搅拌机中的混合特性,以粉煤灰和污泥颗粒物料为例,利用EDEM仿真软件对连续性物料的混合过程进行了模拟。首先分析了搅拌机内物料的混合机理;建立了相应的搅拌机模型和颗粒接触模型,最后对比了不同搅拌转速对物料的连续性以及混合度的影响。结果表明,在高转速下,物料出料率较低,连续性较差,但是物料的混合度相对较好。综合考虑连续性和混合度在实际生产过程中的要求,最终确定了比较合适的搅拌转速。 展开更多
关键词 立式搅拌机 连续性 出料率 混合度
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Association of Streptococcus bovis presence in colonic content with advanced colonic lesion 被引量:9
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作者 maya Paritsky Nina Pastukh +2 位作者 Diana Brodsky Natalya Isakovich Avi Peretz 《World Journal of Gastroenterology》 SCIE CAS 2015年第18期5663-5667,共5页
AIM:To prospectively examine the association between presence of Streptococcus bovis(S.bovis)in colonic suction fluid and the endoscopic findings on colonoscopy.METHODS:From May 2012 to March 2013,203 consecutivepatie... AIM:To prospectively examine the association between presence of Streptococcus bovis(S.bovis)in colonic suction fluid and the endoscopic findings on colonoscopy.METHODS:From May 2012 to March 2013,203 consecutivepatients who underwent colonoscopy for any reason were enrolled in the study.Exclusion criteria included:antibiotic use in the previous month,age younger than18 years,and inadequate preparation for colonoscopy.The colonoscopy was performed for the total length of the colon or to the occluding tumor.The endoscopic findings were registered.Samples were obtained proximal to the colonoscopic part of the suction tube from each patient and sent to the clinical microbiology laboratory for isolation and identification of S.bovis.Samples were incubated in enrichment media with addition of antibiotic disks for inhibition of growth of Gram-negative rods.The samples were seeded on differential growth media;suspected positive colonies were isolated and identified with Gram staining,catalase,and pyrrolidonyl arylamidase tests,and further identified using a VITEK2 system.Statistical analyses were performed using the Student’s t andχ2 tests.RESULTS:Of the 203 patients recruited,49(24%)patients were found to be S.bovis carriers;of them,the endoscopic findings included:17(34.7%)cases with malignant tumors,11(22.4%)with large polyps,5(10.2%)with medium-sized polyps,6(12.2%)with small polyps,4(8.1%)with colitis,and 6(12.2%)normal colonoscopies.Of 154 patients found negative for S.bovis,the endoscopic findings included:none with malignant tumors,9(5.8%)cases with large polyps,11(7.1%)with medium-sized polyps,26(16.9%)with small polyps,7(4.5%)with colitis,and101(65.6%)normal colonoscopies.S.bovis(Grampositive coccus)is considered part of the normal intestinal flora.There is an association between S.bovis bacteremia and colonic neoplasia.It is not well understood whether the bacterium has a pathogenetic role in the development of neoplasia or constitutes an epiphenomenon of colorectal neoplasms.There was a clear relationship 展开更多
关键词 COLON cancer COLONOSCOPY Culture Screening STREPTOCOCCUS BOVIS
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术中二维相干光断层扫描作为前节手术的一个新工具 被引量:8
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作者 Gerd Geerling maya Müller +6 位作者 Christian Winter Hans Hoerauf Stefan Oelckers Horst Laqua Reginald Birngruber 李晓宁(译) 任泽钦(校) 《美国医学会眼科杂志(中文版)》 2005年第4期221-224,255,共5页
我们测试了1310nm相干光断层扫描仪与手术显微镜前部镜头的分光镜连接后对前节手术过程中术中的非接触性成像。这项对相干光断层成像技术的新改进可完成前节手术术中角膜、巩膜的高分辨率横断面的成像与厚度测量。其在板层切开技术如深... 我们测试了1310nm相干光断层扫描仪与手术显微镜前部镜头的分光镜连接后对前节手术过程中术中的非接触性成像。这项对相干光断层成像技术的新改进可完成前节手术术中角膜、巩膜的高分辨率横断面的成像与厚度测量。其在板层切开技术如深层前板层角膜移植术和小梁切除术中尤为有用。 展开更多
关键词 断层扫描仪 手术过程 相干光 术中 前板层角膜移植术 断层成像技术 工具 二维 手术显微镜 非接触性
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Real-Time Static Hand Gesture Recognition for American Sign Language (ASL) in Complex Background 被引量:7
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作者 Jayashree R. Pansare Shravan H. Gawande maya Ingle 《Journal of Signal and Information Processing》 2012年第3期364-367,共4页
Hand gestures are powerful means of communication among humans and sign language is the most natural and expressive way of communication for dump and deaf people. In this work, real-time hand gesture system is propose... Hand gestures are powerful means of communication among humans and sign language is the most natural and expressive way of communication for dump and deaf people. In this work, real-time hand gesture system is proposed. Experimental setup of the system uses fixed position low-cost web camera with 10 mega pixel resolution mounted on the top of monitor of computer which captures snapshot using Red Green Blue [RGB] color space from fixed distance. This work is divided into four stages such as image preprocessing, region extraction, feature extraction, feature matching. First stage converts captured RGB image into binary image using gray threshold method with noise removed using median filter [medfilt2] and Guassian filter, followed by morphological operations. Second stage extracts hand region using blob and crop is applied for getting region of interest and then “Sobel” edge detection is applied on extracted region. Third stage produces feature vector as centroid and area of edge, which will be compared with feature vectors of a training dataset of gestures using Euclidian distance in the fourth stage. Least Euclidian distance gives recognition of perfect matching gesture for display of ASL alphabet, meaningful words using file handling. This paper includes experiments for 26 static hand gestures related to A-Z alphabets. Training dataset consists of 100 samples of each ASL symbol in different lightning conditions, different sizes and shapes of hand. This gesture recognition system can reliably recognize single-hand gestures in real time and can achieve a 90.19% recognition rate in complex background with a “minimum-possible constraints” approach. 展开更多
关键词 Image PREPROCESSING Region EXTRACTION FEATURE EXTRACTION MEDIAN Filter ASL
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Evaluation of Human Impacts on Bartlett Pond Ecosystem, Laredo, Southern Texas, USA, through Empirical Modeling
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作者 maya P. Bhatt Amede Rubio +6 位作者 Ganesh B. Malla Cristobal Lopez Virginia Morales Erick Vazquez Cano David Marquez Orlando Berumen Alvarez Alfred Addo-Mensah 《Journal of Environmental Protection》 2024年第4期497-526,共30页
The trace elements chemistry of Bartlett Pond, a small shallow wetland pond in Laredo, Southern Texas, was sampled to evaluate the dynamics of trace elements impacts on water quality and ecosystems ecology of the pond... The trace elements chemistry of Bartlett Pond, a small shallow wetland pond in Laredo, Southern Texas, was sampled to evaluate the dynamics of trace elements impacts on water quality and ecosystems ecology of the pond. Two types of fish (bass and tilapia) were also sampled to see the trace element accumulation in different parts of their body. The concentrations of trace elements in water samples were found in the following order: Fe &Gt;Sb > Pb > As &Gt;Co > Tl > Cr > Cd within Bartlett Pond. Overall, the water quality of the pond is unacceptable for drinking and any other purposes as trace element concentrations (e.g. As, Cd, Co, Cr, Pb, Fe, Sb and Tl) are exceedingly higher (several fold) than the WHO and US EPA guidelines. Predictive and correlation analysis shows that most trace elements exhibit a strong positive correlation among them indicating the same anthropogenic sources and biogeochemical processes regulate these trace elements within the pond. Distributions of the trace elements in water exhibit different shapes mostly as positively skewed distribution for As, Cd, Co, Cr, and Tl, symmetrical distribution for Fe and almost symmetrical distribution for Pb and Sb. Concentrations of As, Co and Tl accumulated much higher in different parts of the Bass than Tilapia fish. The concentrations of As, Tl, Co, and Sb appeared significantly higher in different parts of the body of both Bass and Tilapia than the maximum SRM certified values. Accumulation of these contaminants in fish tissues pose increased health risks to humans who consume these contaminated fish although fishing is prohibited. Anthropogenic activities in the region primarily degrade the whole pond ecosystem ecology of the Bartlett Pond and waters of this pond to be not recommended for any use. These findings may be useful for the scientific community and concerned authorities to improve understanding about these precious natural resources and conservation of the ecosystem ecology. 展开更多
关键词 Trace Elements Bartlett Pond Laredo Southern Texas WETLANDS Ecosystem Ecology
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评估农林业适应气候变化的潜力:尼泊尔拉姆琼案例研究
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作者 JOSHI Rajeev TAMANG Gyanu maya +3 位作者 BHANDARI Prativa SHARMA Bharat JOSHI Dikshya BHUSAL Shushma 《Journal of Resources and Ecology》 CSCD 2024年第2期280-292,共13页
农林系统具有多种效益,包括通过使用肥用树种来提高土壤质量,通过树冠改善小气候,以及生产薪柴和其他医药产品等森林产品以提高经济效益。农林复合经营有助于更好的土地管理、生计多样化和提高土地生产力。然而,政策制定者和其他利益相... 农林系统具有多种效益,包括通过使用肥用树种来提高土壤质量,通过树冠改善小气候,以及生产薪柴和其他医药产品等森林产品以提高经济效益。农林复合经营有助于更好的土地管理、生计多样化和提高土地生产力。然而,政策制定者和其他利益相关方在农林业作为气候变化适应战略中作用的争辩却越来越多。本研究的目的是评估农林业作为气候变化适应战略的潜力。数据主要通过问卷调查从拉姆琼县Taksar的120名受访者中收集,采用卡方检验和二元logistic模型分析了影响气候变化适应策略的家庭选择因素。同样,通过访谈、讨论和观察以及后续的文件分析,对所获得的数据进行三角互证和验证。研究表明,农民采取了许多应对气候变化的策略,这些策略包括农牧多样化(71%)、使用改良作物品种、化肥和农药(73%)、农林复合经营(68%)、创收多样化(72%)、改变作物种植日期(57%)和复种措施(67%)等。从卡方检验和二元logistic模型中发现,“耕作经验”、“教育水平”、“农场规模”和“性别”对气候变化适应策略具有显著影响。农林复合经营具有不同的效益,如增加河流汇水(79.2%)、改善小气候(80.8%)、增加木材产品(71.7%)、提高粮食产量(83.3%)、改善牲畜健康和畜产品(77.5%)、提高土壤肥力(84.2%)和多样化生计选择(82.2%)。基于这些发现,该研究得出结论:农林复合经营是一种可以减少气候变化对当地环境影响的农业生产方法,推广和采用农林业可以帮助当地社区减少气候变化的影响。 展开更多
关键词 气候变化 适应策略 当地社区 复种
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Further Studies of the Cap Pushing Response in Honey Bees (Apis mellifera)
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作者 Riley J. Wincheski Kiri Li N. Stauch +3 位作者 Laura M. Grossner maya B. Zepeda James W. Grice Charles I. Abramson 《Natural Science》 2024年第5期45-64,共20页
The Cap Pushing Response (CPR) is a free-flying technique used to study learning and memory in honey bees (Apis mellifera). The series of experiments outlined in this paper aimed to test whether honey bees exhibit the... The Cap Pushing Response (CPR) is a free-flying technique used to study learning and memory in honey bees (Apis mellifera). The series of experiments outlined in this paper aimed to test whether honey bees exhibit the cognitive concept of “expectancy” utilizing the CPR in a weight differentiation paradigm. Five previous experiments in our laboratory have explored whether the concept of expectancy can account for honey bee performance and have all failed to support the cognitive interpretation. The first experiment examined if bees could differentiate between the two caps in the amount of force they used to push the cap and the distance the cap was pushed when the caps were presented one at a time. The second experiment explored cap weight preference by presenting bees with a choice between the two caps. The third and fourth experiments tested the bee’s ability to expect reward or punishment based on cap weight. Results revealed that bees were found to have a strong preference for the light cap and therefore were not able to expect reward or punishment based on cap weight. These experiments contribute to the debate on whether bees have “cognitive” representations and continue to support the behaviorist interpretation. 展开更多
关键词 Apis mellifera Cap Pushing Response COGNITION LEARNING
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利用强子探针研究奇特原子核的点质子分布半径及强子探针效应
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作者 张寂潮 孙保华 +34 位作者 Isao Tanihata Rituparna Kanungo Christoph Scheidenberger Satoru Terashima 王枫 Frederic Ameil Joel Atkinson Yassid Ayyad Soumya Bagchi Dolores Cortina-Gil Iris Dillmann Alfredo Estradé Alexey Evdokimov Fabio Farinon Hans Geissel Giulia Guastalla Rudolf Janik Satbir Kaur Ronja Knöbel Jan Kurcewicz Yury Litvinov Michele Marta Magdalena Mostazo Ivan Mukha Chiara Nociforo Hooi Jin Ong Stephane Pietri Andrej Prochazka Branislav Sitar Peter Strmen maya Takechi Junki Tanaka Jossitt Vargas Helmut Weick John Stuart Winfield 《Science Bulletin》 SCIE EI CAS CSCD 2024年第11期1647-1652,共6页
We report the charge-changing cross sections(σ_(cc))of 24 p-shell nuclides on both hydrogen and carbon at about 900A MeV,of which^(8,9)Li,^(10–12)Be,^(10,14,15)B,^(14,15,17–22)N and^(16)O on hydrogen and^(8,9)Li on... We report the charge-changing cross sections(σ_(cc))of 24 p-shell nuclides on both hydrogen and carbon at about 900A MeV,of which^(8,9)Li,^(10–12)Be,^(10,14,15)B,^(14,15,17–22)N and^(16)O on hydrogen and^(8,9)Li on carbon are for the first time.Benefiting from the data set,we found a new and robust relationship between the scaling factor of the Glauber model calculations and the separation energies of the nuclei of interest on both targets.This allows us to deduce proton radii(R_p)for the first time from the cross sections on hydrogen.Nearly identical R_p values are deduced from both target data for the neutron-rich carbon isotopes;however,the R_p from the hydrogen target is systematically smaller in the neutron-rich nitrogen isotopes.This calls for further experimental and theoretical investigations. 展开更多
关键词 Exotic nuclei Nuclear size Reaction cross section Glauber model Radioactive ion beam
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Aqueous Extract of Ceiba pentandra Stimulates the Production of Fetal Hemoglobin in Sickle Cell Patients
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作者 Marie Miezi Nsimba Magain Barihuta Mihatano +4 位作者 Blaise maya Mbamu Aline Diza Lubongo Thoms Nzaji Kolombo Josué Matadi Mukengeshaie José Nzunzu Lami 《Journal of Biosciences and Medicines》 2024年第8期295-306,共12页
Subsequent studies have demonstrated the reversed activity of the aqueous extract of Ceiba pentandra on the deformity of sickled red blood cells in hypoxia conditions. The observation which related to an in vitro stud... Subsequent studies have demonstrated the reversed activity of the aqueous extract of Ceiba pentandra on the deformity of sickled red blood cells in hypoxia conditions. The observation which related to an in vitro study had given rise to hopes as to the management of sickle cell disease (SCD) by the use of this plant species. In this paper, the authors aimed to investigate the effect of the aqueous extract of C. pentandra on the production of fetal hemoglobin in SCD patients. The work carried out hemoglobin electrophoresis, for a period of six months, on blood samples from SCD patients who voluntarily undergone routine treatment, based on the medicinal recipe prepared from the bark of the trunk and branches of C. pentandra, in a hospital center of herbal medicines located in Kinshasa. The medicinal recipe called BEAT-SS is a patented product of the hospital center named Centre de Phytothérapie Moderne NIECA. Blood samples from patients under treatment were taken to evaluate the behavior of different forms of hemoglobin (hemoglobin S, hemoglobin F and hemoglobin A2). Agarose gel electrophoresis with integrated reading was used for the separation of the different forms of hemoglobin, as well as their dosage on each sample of sickle blood. A reduction in the proportion of hemoglobin S and an increase in the proportion of fetal hemoglobin were found in all sickle cell patients during the treatment period. This observation could affirm that the management of sickle cell patients using the recipe prepared from the aqueous extract of C. pentandra could increase the level of fetal hemoglobin in these patients. 展开更多
关键词 Sickle Cell Disease Hemoglobin S Fetal Hemoglobin Ceiba pentandra
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An Alzheimer's Disease-Relevant Presenilin-1 Mutation Augments Amyloid-Beta-Induced Oligodendrocyte Dysfunction 被引量:6
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作者 maya K.DESAI BRENDAN J.GUERCIO +1 位作者 WADE C.NARROW WILLIAM J.BOWERS 《神经损伤与功能重建》 2011年第2期128-141,共14页
研究表明,家族性阿尔茨海默病(FAD)患者处于无症状或临床前阶段时,脑白质即出现病理改变。此种改变在髓鞘破坏及阿尔茨海默病(AD)病理生理中的作用有待进一步研究阐明。笔者前期研究证实,三重转基因AD小鼠(人淀粉前体蛋白基因的Swedish... 研究表明,家族性阿尔茨海默病(FAD)患者处于无症状或临床前阶段时,脑白质即出现病理改变。此种改变在髓鞘破坏及阿尔茨海默病(AD)病理生理中的作用有待进一步研究阐明。笔者前期研究证实,三重转基因AD小鼠(人淀粉前体蛋白基因的Swedish突变,早老素-1 M146V(PS1M146V)敲入突变及tauP301L突变)表现出类似FAD患者的髓鞘破坏,Aβ1-42促进了白质病变。本研究离体实验证实,PS1M146V变异导致小鼠少突胶质前体细胞在分化过程中易出现类似Aβ1-42诱导的变化。PS1M146V的表达损伤少突胶质前体细胞的功能并影响髓鞘碱性蛋白的分布,暴露于Aβ1-42加重此影响。由PS1M146V及Aβ1-42导致的髓鞘破坏及髓鞘碱性蛋白在亚细胞结构中的误定位可被TWS119(糖原合成激酶(GSK)-3β抑制剂)抑制,提示GSK-3β激酶活动在此病理过程中有重要作用。综上所述,本研究有助于增加对AD早期无症状阶段,由PS1M146V及Aβ1-42导致少突胶质细胞功能异常及髓鞘损伤的机制的理解,并提供了针对少突胶质细胞预防AD相关白质病变的新的治疗靶点。 展开更多
关键词 阿尔茨海默病 白质 髓磷脂 少突胶质细胞 髓鞘碱性蛋白 淀粉β样蛋白 早老素-1 3重转基因AD
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Function and regulation of self-reactive marginal zone B cells in autoimmune arthritis 被引量:5
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作者 Anna-Karin E Palm Heike C Friedrich +3 位作者 Anja Mezger maya Salomonsson Linda K Myers Sandra Kleinau 《Cellular & Molecular Immunology》 SCIE CAS CSCD 2015年第4期493-503,共11页
Polyreactive innate-type B cells account for many B cells expressing self-reactivity in the periphery. Improper regulation of these B cells may be an important factor that underlies autoimmune disease. Here we have ex... Polyreactive innate-type B cells account for many B cells expressing self-reactivity in the periphery. Improper regulation of these B cells may be an important factor that underlies autoimmune disease. Here we have explored the influence of self-reactive innate B cells in the development of collagen-induced arthritis (CIA), a mouse model of rheumatoid arthritis. We show that splenic marginal zone (MZ), but not B- 1 B cells exhibit spontaneous IgM reactivity to autologous collagen II in na'='ve mice. Upon immunization with heterologous collagen II in complete Freund's adjuvant the collagen-reactive MZ B cells expanded rapidly, while the B-1 B cells showed a modest anti-collagen response. The MZ B cells were easily activated by toll-like receptor (TLR) 4 and 9-1igands in vitro, inducing proliferation and cytokine secretion, implying that dual engagement of the B-cell receptor and TLRs may promote the immune response to self-antigen. Furthermore, collagen-primed MZ B cells showed significant antigen-presenting capacity as reflected by cognate T-cell proliferation in vitroand induction of IgG anti-collagen antibodies in vivo. MZ B cells that were deficient in complement receptors I and 2 demonstrated increased proliferation and cytokine production, while Fcy receptor lib deficiency of the cells lead to increased cytokine production and antigen presentation. In conclusion, our data highlight self-reactive MZ B cells as initiators of the autoimmune response in CIA, where complement and Fc receptors are relevant in controlling the self-reactivity in the cells. 展开更多
关键词 ARTHRITIS complement receptors Fc receptors marginal zone B cells mice
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Recent antibacterial agents from biomass derivatives:Characteristics and applications 被引量:1
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作者 Nissa Nurfajrin Solihat Alif Faturahman Hidayat +11 位作者 R.A.Ilyas Senthil Muthu Kumar Thiagamani Nur Izyan Wan Azeele Fahriya Puspita Sari maya Ismayati Mohammad Irfan Bakshi Zaharaddeen N.Garba M.Hazwan Hussin Witta Kartika Restu Wasrin Syafii Harits Atika Ariyanta Widya Fatriasari 《Journal of Bioresources and Bioproducts》 EI CSCD 2024年第3期283-309,共27页
Enhancing awareness of personal cleanliness and antibacterial resistance has intensified the antibacterial substance request on consumable products. Antibacterial agents that have been commercialized nowadays are prod... Enhancing awareness of personal cleanliness and antibacterial resistance has intensified the antibacterial substance request on consumable products. Antibacterial agents that have been commercialized nowadays are produced from inorganic and non-renewable substances. This provides several drawbacks, particularly against health and environmental issues. Therefore, many scientists work on substituting fossil-fuel-based antibacterial agents with natural ones such as from biomass. Biomass derivatives, natural abundances of biopolymers in the world, amount to major compounds including polysaccharides (cellulose, hemicellulose, and chitosan) and polyphenol (tannin and lignin) substances which are capable to combat the growth of Gram-positive bacteria and Gram-negative bacteria. To date, no report focuses on a deep understanding of antibacterial properties derived from biomass and the internal and external factors effects. This work provides that gap because comprehensive knowledge is necessary before applying biomass to the products. The potency of biomass derivatives as antibacterial additives is also summarized. Basic knowledge of antibacterial characteristics to the application in products is highlighted in this review. Besides, the discussion about challenges and future perspectives is also delivered. 展开更多
关键词 ANTIBACTERIAL APPLICATION Biomass derivatives CHALLENGE Future perspectives
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The role of DJ-1 in the oxidative stress cell death cascade after stroke 被引量:5
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作者 Paolina Pantcheva maya Elias +3 位作者 Kelsey Duncan Cesar V.Borlongan Naoki Tajiri Yuji Kaneko 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第15期1430-1433,共4页
Oxidative stress is closely associated with secondary cell death in many disorders of the central nervous system including stroke, Parkinson's disease, Alzheimer's disease. Among many aber-rant oxidative stress-asso... Oxidative stress is closely associated with secondary cell death in many disorders of the central nervous system including stroke, Parkinson's disease, Alzheimer's disease. Among many aber-rant oxidative stress-associated proteins, DJ-1 has been associated with the oxidative stress cell death cascade primarily in Parkinson's disease. Although principally expressed in the cytoplasm and nucleus, DJ-1 can be secreted into the serum under pathological condition. Recently, a close pathological association between DJ-I and oxidative stress in stroke has been implicated. To this end, we and others have demonstrated the important role of mitochondria in neuroprotection for stroke by demonstrating that the translocation of DJ-1 in the mitochondria could potentially mitigate mitochondrial injury. Here, we discuss our recent findings testing the hypothesis that DJ- 1 not only functions as a form of intracellular protection from oxidative stress, but that it also utilizes paracrine and/or autocrine cues in order to accomplish extracellular signaling between neighboring neuronal cells, resulting in neuroprotection. This article highlights recent evidence supporting the status of DJ-1 as key anti-oxidative stress therapeutic target for stroke. 展开更多
关键词 cerebral ischemia NEUROPROTECTION MITOCHONDRIA TRANSLOCATION extracellular signaling
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A research progress review on regional extreme events 被引量:5
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作者 REN Fu-Min Blair TREWIN +4 位作者 Manola BRUNET Pattanaik DUSHMANTA Andreas WALTER Omar BADDOUR maya KORBER 《Advances in Climate Change Research》 SCIE CSCD 2018年第3期161-169,共9页
An extreme (weather and climate) event does not only mean that an extreme occurs at a location, but more generally it can impact a certainarea and last a certain period of time, which is defined as a regional extrem... An extreme (weather and climate) event does not only mean that an extreme occurs at a location, but more generally it can impact a certainarea and last a certain period of time, which is defined as a regional extreme event (REE) with a certain impacted area and duration. The conceptof REE has been defined to allow mainly objective assessment of the events without a pre-determined boundary and duration. This paper reviewsthe studies on REEs published during the past 20 years, especially recent years. Mainly in view of methodology, these studies can be divided intothree types studies focusing on spatial simultaneity, studies focusing on temporal persistence, and studies identifying REEs. The methodsidentifying REEs include two kinds, e.g., type-I methods stressing REE's temporal persistence within a relatively certain area and type-IImethods focusing on catching a complete REE. Identification methods proposed in this paper could provide valuable information for variouspurposes, such as real-time monitoring, estimating long-term changes, mechanism diagnosis, forecasting study and even attribution analysis.Research on REEs is important for objectively defining extreme weather and climate events, which depends on the spatial and temporal scales ofinterest. Such an objective definition will support ongoing climate monitoring and improve the assessment of how regional extreme events havechanged over time. 展开更多
关键词 EXTREME (weather and climate) EVENTS REGIONAL EXTREME EVENTS Research progress REVIEW
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