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鼠源休眠蛋白具有抑制内皮细胞增殖和诱导细胞凋亡的活性(英文)

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生物化学与生物物理学报 2002年第2期34卷 138-142页

作者：徐韧辛利樊懿孟海蓉李载平甘人宝中国科学院上海生命科学研究院生物化学与细胞生物学研究所上海中医药大学

内皮抑素 (endostatin)是最近发现的一种具有抑制血管生长的蛋白质。休眠蛋白 (restin)是内皮抑素的同源蛋白质 ,最早由Ramchandran等人发现 ,它来源于胶原蛋白XV的羧端非胶原蛋白结构域 (NC1)。为了研究鼠源休眠蛋白对内皮细胞生长的影... 详细信息

内皮抑素 (endostatin)是最近发现的一种具有抑制血管生长的蛋白质。休眠蛋白 (restin)是内皮抑素的同源蛋白质 ,最早由Ramchandran等人发现 ,它来源于胶原蛋白XV的羧端非胶原蛋白结构域 (NC1)。为了研究鼠源休眠蛋白对内皮细胞生长的影响 ,利用RT PCR从鼠肌肉中扩增出它的基因 ,克隆入原核表达载体pQE32。诱导后 ,重组蛋白质以包涵体形式高效表达 ,表达量约占菌体总蛋白质的 6 0 %～ 70 %。重组蛋白质经纯化复性后 ,可以特异地抑制bFGF刺激的牛主动脉内皮细胞的增殖 ,但是休眠蛋白的抑制活性比内皮抑素活性稍低。流式细胞仪检测发现 ,休眠蛋白可以引起内皮细胞的细胞周期的改变 ,并且引起细胞凋亡

关键词：休眠蛋白内皮抑素胶原蛋白XV 血管生长抑制细胞凋亡

菹草(Potamogeton crispus)的花粉形态与其生态因子

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微体古生物学报 2008年第1期25卷 91-96页

作者：张颖周忠泽赵秀侠许仁鑫安徽大学生命科学学院安徽省生态工程与生物技术重点实验室合肥230039

应用光学显微镜、扫描电镜和透射电镜对安徽大学校内水池中眼子菜科植物菹草的花粉形态进行了观察和研究。结果表明花粉粒球形至近球形,花粉大小为21.0—29.0μm,平均为24.5μm。无萌发孔。光学显微镜下,花粉外壁纹饰为网状,外壁厚约4.1... 详细信息

应用光学显微镜、扫描电镜和透射电镜对安徽大学校内水池中眼子菜科植物菹草的花粉形态进行了观察和研究。结果表明花粉粒球形至近球形,花粉大小为21.0—29.0μm,平均为24.5μm。无萌发孔。光学显微镜下,花粉外壁纹饰为网状,外壁厚约4.1μm,两层明显,外层较内层厚。在扫描电镜下花粉表面具粗网状纹饰,网脊窄。在透射电镜下,花粉外壁为三层组成,即覆盖层、柱状层和基层。外壁内层不明显。覆盖层不连续,为半覆盖层;柱状层小柱发达;基层较厚。同时研究了菹草花粉的地理分布及其与生态因子的关系。根据菹草植物赖以生存的生态因子,得出菹草花粉分布区的主要生态因子,包括地理位置、海拔高度、年降水量、年积温及生境,为利用地层中眼子菜科化石花粉重建古气候、古环境及气候变迁提供了现代孢粉学资料和依据。

关键词：菹草(Potamogeton crispus) 花粉形态古植被古气候

安徽鹞落坪国家自然保护区植物的花粉形态与其生态因子

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微体古生物学报 2008年第2期25卷 166-184页

作者：陈延松周忠泽许仁鑫沈军安徽大学生命科学学院安徽省生态工程与生物技术重点实验室安徽大学生命科学学院生物多样性与湿地生态研究所合肥230039 合肥师范学院生物系合肥230061

应用光学显微镜对安徽省鹞落坪国家级自然保护区7月份开花的25科41属47种1变种植物的花粉形态进行了观察和研究。结果表明花粉粒扁球形至超长球形,P/E值最大的为安徽贝母(Fritillaria anhuiensis *** et ***),大小为1.71(1.28—2.30)μm... 详细信息

应用光学显微镜对安徽省鹞落坪国家级自然保护区7月份开花的25科41属47种1变种植物的花粉形态进行了观察和研究。结果表明花粉粒扁球形至超长球形,P/E值最大的为安徽贝母(Fritillaria anhuiensis *** et ***),大小为1.71(1.28—2.30)μm,最小的为粉花绣线菊(Spiraea japonica L.),大小为0.83(0.58—0.97)μm;花粉最大的为萱草[Hemerocallis fulva(L.)L.],大小为93.8(85.0—100.0)×61.1(51.3—70.0)μm;最小的为草绣球[Cardiandra moellendorffii(Hance)Migo],大小为11.1(9.5—12.5)×8.8(7.5—10.0)μm。萌发孔主要有单沟(8.3%)、3—4沟(18.8%)、多沟(8.3%)、3—4孔沟(58.3%)、散孔(4.2%)、无萌发孔(2.1%)等类型。外壁纹饰主要有刺状(12.5%)、细网状(33.3%)、粗网状(16.7%)、颗粒状(25.0%)及无明显纹饰(12.5%)等类型。同时研究了其生态因子,包括地理位置、海拔高度、年降水量、年积温及生境等,特别提供了7月份的气候因子,得出这些花粉分布区的主要生态因子,为利用地层中相应化石花粉重建大别山地区古植被、古环境及气候变迁提供了现代孢粉学资料和依据,也为这些植物的现代地理分布提供了科学依据。

关键词：花粉形态古植被古气候鹞落坪国家自然保护区安徽

有机膨润土增稠低温固化乙烯基酯树脂预浸料的性能

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复合材料科学与工程 2022年第8期 89-92页

作者：刘晓帆吴书广徐任信武汉理工大学材料科学与工程学院武汉430000 宜昌测试技术研究所上海200000

为制备一种低温固化乙烯基酯树脂预浸料并研究增稠剂含量对预浸料及复合材料性能的影响,采用有机膨润土为增稠剂、无碱玻璃纤维布为增强材料,以一步浸渍法制备了纤维预浸料;通过真空袋压成型,在60℃下预热30 min,90℃下固化1 h,得到固... 详细信息

为制备一种低温固化乙烯基酯树脂预浸料并研究增稠剂含量对预浸料及复合材料性能的影响,采用有机膨润土为增稠剂、无碱玻璃纤维布为增强材料,以一步浸渍法制备了纤维预浸料;通过真空袋压成型,在60℃下预热30 min,90℃下固化1 h,得到固化程度良好的复合材料。研究不同含量有机膨润土预浸料的工艺性能及复合材料的力学性能,结果表明,各预浸料树脂含量有细微差别,黏性级别均为1级,工艺性能良好。复合材料的力学性能在膨润土质量含量为10%时,拉伸强度为395 MPa,弯曲强度为382 MPa,压缩强度为201 MPa,综合力学性能最为优异。

关键词：乙烯基酯树脂预浸料低温固化力学性能复合材料

Seasonal dynamics of wintering waterbirds in two shallow lakes along Yangtze River in Anhui Province

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Zoological Research 2011年第5期32卷 540-548页

作者：陈锦云周立志周波许仁鑫朱文中徐文彬安徽大学资源与环境工程学院安徽大学生物多样性与湿地生态研究所安徽合肥230601 淮南师范学院生命科学系安徽淮南232001 安徽安庆沿江湿地自然保护区安徽安庆246001 升金湖国家级自然保护区安徽东至247200

The shallow lake wetlands in the middle and lower Yangtze River floodplain are important wintering and stopover habitats for migratory waterbirds on the East Asia-Australia *** increasing fishery practices in recent years,however,the wetlands have deteriorated significantly and now threaten wintering *** gain insight into the influence of deteriorating wetlands on waterbirds,we conducted a survey of wintering waterbird species,population size,and distribution across 11 belt transects in Caizi Lake and Shengjin Lake,two shallow lakes along the Yangtze River in Anhui Province from November 2007-April 2008 and from November 2008-April 2009,*** impacts of different fishery patterns on the distribution of waterbirds were also analyzed.A total of 43 waterbirds species belong to 7 orders of 12 families were counted during the surveys,of which 38 were found in Caizi Lake with a density of 8.2 ind./hm2,and 42 in Shengjin Lake with a density of 3.5 ind./***（Anser cygnoides）,bean geese（Anser fabalis）,tundra swan（Cygnus columbianus）,and dunlin（Calidris alpina） were the dominant species in the two shallow *** number and individual assemble reached maximum at the end of December and in early January of the following year,without coincidence of the largest flock for different ecological *** on waterbird diversity across the 11 belt transects and the fishery patterns,habitats could be divided into three ***,Anseriformes and Charadriiformes had relatively higher densities in the natural fishery zones and lower densities in the cage fishery zones;whereas,the density of Ardeidae showed little change across all lake *** is important to develop sustainable fishery patterns in shallow lakes along the middle and lower Yangtze River floodplain to better protect resources of wintering waterbirds.

关键词： Wintering waterbirds Community diversity Seasonal dynamic Fishery disturbance Caizi Lake Shengjin Lake

Inhibitory gamma-aminobutyric acidergic neurons in the anterior cingulate cortex participate in the comorbidity of pain and emotion

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Neural Regeneration Research 2025年第10期20卷 2838-2854页

作者： Lu Guan Mengting Qiu Na Li Zhengxiang Zhou Ru Ye Liyan Zhong Yashuang xu Junhui ren Yi Liang Xiaomei Shao Jianqiao Fang Junfan Fang Junying Du Department of Neurobiology and Acupuncture Research Third School of Clinical MedicineZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina Key Laboratory for Research of Acupuncture Treatment and Transformation of Emotional Diseases Third School of Clinical MedicineZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina Fuchun Community Health Service Center of Fuyang District HangzhouZhejiang ProvinceChina

Pain is often comorbid with emotional disorders such as anxiety and *** of the anterior cingulate cortex has been implicated in pain and pain-related negative emotions that arise from impairments in inhibitory gamma-aminobutyric acid *** review primarily aims to outline the main circuitry(including the input and output connectivity)of the anterior cingulate cortex and classification and functions of different gamma-aminobutyric acidergic neurons;it also describes the neurotransmitters/neuromodulators affecting these neurons,their intercommunication with other neurons,and their importance in mental comorbidities associated with chronic pain *** understanding on their role in pain-related mental comorbidities may facilitate the development of more effective treatments for these ***,the mechanisms that regulate gamma-aminobutyric acidergic systems remain *** is also unclear as to whether the mechanisms are presynaptic or *** exploration of the complexities of this system may reveal new pathways for research and drug development.

关键词： anterior cingulate cortex anxiety chronic pain circuit communication comorbidity depression gamma-aminobutyric acidergic neurons parvalbumin neurons synaptic transmission

Aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders:progress of experimental models based on disease pathogenesis

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Neural Regeneration Research 2025年第2期20卷 354-365页

作者： Li xu Huiming xu Changyong Tang Department of Neurology The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong ProvinceChina

Neuromyelitis optica spectrum disorders are neuroinflammatory demyelinating disorders that lead to permanent visual loss and motor *** date,no effective treatment exists as the exact causative mechanism remains ***,experimental models of neuromyelitis optica spectrum disorders are essential for exploring its pathogenesis and in screening for therapeutic *** most patients with neuromyelitis optica spectrum disorders are seropositive for IgG autoantibodies against aquaporin-4,which is highly expressed on the membrane of astrocyte endfeet,most current experimental models are based on aquaporin-4-IgG that initially targets *** experimental models have successfully simulated many pathological features of neuromyelitis optica spectrum disorders,such as aquaporin-4 loss,astrocytopathy,granulocyte and macrophage infiltration,complement activation,demyelination,and neuronal loss;however,they do not fully capture the pathological process of human neuromyelitis optica spectrum *** this review,we summarize the currently known pathogenic mechanisms and the development of associated experimental models in vitro,ex vivo,and in vivo for neuromyelitis optica spectrum disorders,suggest potential pathogenic mechanisms for further investigation,and provide guidance on experimental model *** addition,this review summarizes the latest information on pathologies and therapies for neuromyelitis optica spectrum disorders based on experimental models of aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders,offering further therapeutic targets and a theoretical basis for clinical trials.

关键词： aquaporin-4 experimental model neuromyelitis optica spectrum disorder pathogenesis

Reducing the measurement errors in nonadiabatic holonomic quantum computers

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 64-70页

作者： Guo-Fu xu Department of Physics Shandong University

Nonadiabatic holonomic quantum computers serve as the physical platform for nonadiabatic holonomic quantum *** quantum computation has entered the noisy intermediate-scale era, building accurate intermediate-scale nonadiabatic holonomic quantum computers is clearly necessary. Given that measurements are the sole means of extracting information, they play an indispensable role in nonadiabatic holonomic quantum computers. Accordingly, developing methods to reduce measurement errors in nonadiabatic holonomic quantum computers is of great importance. However, while much attention has been given to the research on nonadiabatic holonomic gates, the research on reducing measurement errors in nonadiabatic holonomic quantum computers is severely lacking. In this study, we propose a measurement error reduction method tailored for intermediate-scale nonadiabatic holonomic quantum computers. The reason we say this is because our method can not only reduce the measurement errors in the computer but also be useful in mitigating errors originating from nonadiabatic holonomic gates. Given these features,our method significantly advances the construction of accurate intermediate-scale nonadiabatic holonomic quantum computers.

关键词： quantum holonomy quantum computation measurement errors

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树脂传递模塑工艺用改性氰酸酯树脂体系研究

热固性树脂 2016年第5期31卷 48-51页

作者：孙煜徐任信王钧杨小利蔡浩鹏武汉理工大学材料科学与工程学院湖北武汉430070

由自制改性剂苯乙烯和丙烯酸正丁酯低聚物及TDE-85环氧树脂协同改性氰酸酯树脂,采用示差扫描量热仪,动态热机械分析仪,力学性能和粘度测试研究了改性后的氰酸酯树脂的性能。结果表明,改性氰酸酯树脂浇铸体玻璃化转变温度高于215℃,TDE-8... 详细信息

由自制改性剂苯乙烯和丙烯酸正丁酯低聚物及TDE-85环氧树脂协同改性氰酸酯树脂,采用示差扫描量热仪,动态热机械分析仪,力学性能和粘度测试研究了改性后的氰酸酯树脂的性能。结果表明,改性氰酸酯树脂浇铸体玻璃化转变温度高于215℃,TDE-85环氧树脂质量分数为15%时,改性氰酸酯树脂浇铸体的综合性能最佳,拉伸强度为45 MPa,弯曲强度为86 MPa,冲击韧性为17 k J/m^2。改性树脂体系室温下6 h内粘度保持在1 000 m Pa·s以下,满足树脂传递模塑成型工艺的要求。

关键词：树脂传递模塑氰酸酯树脂苯乙烯-丙烯酸正丁酯低聚物 TDE-85环氧树脂耐热性力学性能粘度