检索结果-南通市图书馆

Protective effect of bone marrow mesenchymal stem cell-derived exosomes against the reproductive toxicity of cyclophosphamide is associated with the p38MAPK/ERK and AKT signaling pathways

引用

Asian Journal of Andrology 2021年第4期23卷 386-391页

作者： Xiao-Bin Guo jia-wen zhai Hui Xia jian-Kun Yang Jun-Hao Zhou wen-Bin Guo Cheng Yang Ming Xia Kang-Yi Xue Cun-Dong Liu Qi-Zhao Zhou Department of Urology The Third Affiliated Hospital of Southern Medical UniversityGuangzhou 510630China

Spermatogenic dysfunction caused by cyclophosphamide(CP)chemotherapy has seriously influenced the life quality of ***,treatments for CP-induced testicular spermatogenic dysfunction are limited,and the molecular mechanisms are not fully *** the first time,here,we explored the effects of bone marrow mesenchymal stem cell-derived exosomes(BMSC-exos)on CP-induced testicular spermatogenic dysfunction in vitro and in ***-exos could be taken up by spermatogonia(GC1-spg cells).CP-injured GC1-spg cells and BMSC-exos were cocultured at various doses,and then,cell proliferation was measured using 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide(MTT)*** addition,photophosphorylation of extracellular-regulated kinase(ERK),p38 mitogen-activated protein kinase(p38MAPK),and protein kinase B(AKT)proteins was evaluated by western blotting as well as apoptosis in GC1-spg cells measured using flow *** with BMSC-exos enhanced cell proliferation and reduced apoptosis of CP-injured GCI-spg *** levels of ERK,AKT,and p38MAPK proteins were reduced in CP-injured spermatogonia when co-treated with BMSC-exos,indicating that BMSC-exos acted against the reproductive toxicity of CP via the p38MAPK/ERK and AKT signaling *** experiments in vivo,CP-treated rats received BMSC-exos by injection into the tail vein,and testis morphology was compared between treated and control *** showed that transfusion of BMSC-exos inhibited the pathological changes in CP-injured ***,BMSC-exos could counteract the reproductive toxicity of CP via the p38MAPK/ERK and AKT signaling *** findings provide a potential treatment for CP-induced male spermatogenic dysfunction using BMSC-exos.

关键词： bone marrow mesenchymal stem cells cyclophosphamide exosomes reproductive toxicity

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

On Some Sums Involving Small Arithmetic Functions

引用

Acta Mathematica Sinica,English Series 2024年第10期40卷 2497-2518页

作者： wen Guang zhai Department of Mathematics China University of Mining and Technology

Let f be any arithmetic function and define S_f（x）:=Σn≤xf （[x/n]）.If the function f is small,namely,f （n）﹤﹤ nε,then the error term E_f（x） in the asymptotic formula of S_f（x） has the form O(x1/2+ε).In this paper,we shall study the mean square of E_f（x） and establish some new results of E_f（x） for some special functions.

关键词： 11L07 11N37 asymptotic formula exponential sum Small arithmetic function

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Resilience assessment and optimization method of city road network in the post-earthquake emergency period

引用

Earthquake Engineering and Engineering Vibration 2024年第3期23卷 765-779页

作者： Wang Haoran Xiao jia Li Shuang zhai Changhai Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information TechnologyHarbin Institute of TechnologyHarbin 150090China

The post-earthquake emergency period,which is a sensitive time segment just after an event,mainly focuses on saving life and restoring social *** improve the seismic resilience of city road networks,a resilience evaluation method used in the post-earthquake emergency period is *** road seismic damage index of a city road network can consider the influence of roads,bridges and buildings along the roads,*** road capacity after an earthquake.A function index for a city road network is developed,which reflects the connectivity,redundancy,traffic demand and traffic function of the *** optimization model for improving the road repair order in the post-earthquake emergency period is also developed according to the resilience evaluation,to enable decision support for city emergency management and achieve the best seismic resilience of the city road *** optimization model is applied to a city road network and the results illustrate the feasibility of the resilience evaluation and optimization method for a city road network in the post-earthquake emergency period.

关键词： city road network post-earthquake emergency period traffic demand resilience evaluation optimization model

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Ultraviolet Photodetector based on Sr_(2)Nb_(3)O_(10) Perovskite Nanosheets

引用

Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 282-287页

作者：张斌斌 jia Mengmeng LIANG Qi WU Jinsong zhai Junyi 李宝文 School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China CAS Center for Excellence in Nanoscience Beijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijin 100083China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Liquid-phase exfoliation was employed to synthesize Sr_(2)Nb_(3)O_(10) perovskite nanosheets with thicknesses down to 1.76 *** electron microscopy(TEM),atomic force microscope(AFM),X-ray photoelectron spectrometer(XPS),and other characterization techniques were used to evaluate the atomic structure and chemical composition of the exfoliated nanosheets.A UV photodetector based on individual Sr_(2)Nb_(3)O_(10) nanosheets was prepared to demonstrate the application of an ultraviolet(UV) *** UV photodetector exhibited outstanding photocurrent and responsivity with a responsivity of 3×10^(5) A·W^(-1) at 5 V bias under 280 nm illumination,a photocurrent of 60 nA,and an on/off ratio of 3×10^(2).

关键词： perovskite nanosheets liquid-phase exfoliation ultraviolet photodetector

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Combined application of organic fertilizer and chemical fertilizer alleviates the kernel position effect in summer maize by promoting post-silking nitrogen uptake and dry matter accumulation

引用

Journal of Integrative Agriculture 2024年第4期23卷 1179-1194页

作者： Lichao zhai Lihua Zhang Yongzeng Cui Lifang zhai Mengjing Zheng Yanrong Yao Jingting Zhang Wanbin Hou Liyong Wu Xiuling jia Institute of Cereal and Oil Crops Hebei Academy of Agriculture and Forestry Sciences/Key Laboratory of Crop Cultivation Physiology and Green Production of Hebei ProvinceShijiazhuang 050035China Hebei Science and Technology Innovation Service Center Shijiazhuang 050051China Yongnian Agricultural Technology Extension Center Handan 057150China Ningjin Agricultural Technology Extension Center Xingtai 055550China

Adjusting agronomic measures to alleviate the kernel position effect in maize is important for ensuring high *** order to clarify whether the combined application of organic fertilizer and chemical fertilizer(CAOFCF)can alleviate the kernel position effect of summer maize,field experiments were conducted during the 2019 and 2020 growing seasons,and five treatments were assessed:CF,100%chemical fertilizer;OFCF1,15%organic fertilizer+85%chemical fertilizer;OFCF2,30%organic fertilizer+70%chemical fertilizer;OFCF3,45%organic fertilizer+55%chemical fertilizer;and OFCF4,60%organic fertilizer+40%chemical *** with the CF treatment,the OFCF1 and OFCF2 treatments significantly alleviated the kernel position effect by increasing the weight ratio of inferior kernels to superior kernels and reducing the weight gap between the superior and inferior *** effects were largely due to the improved filling and starch accumulation of inferior ***,there were no obvious differences in the kernel position effect among plants treated with CF,OFCF3,or OFCF4 in most *** area indexes,post-silking photosynthetic rates,and net assimilation rates were higher in plants treated with OFCF1 or OFCF2 than in those treated with CF,reflecting an enhanced photosynthetic capacity and improved postsilking dry matter accumulation(DMA)in the plants treated with OFCF1 or *** with the CF treatment,the OFCF1 and OFCF2 treatments increased post-silking N uptake by 66.3 and 75.5%,respectively,which was the major factor driving post-silking photosynthetic capacity and ***,the increases in root DMA and zeatin riboside content observed following the OFCF1 and OFCF2 treatments resulted in reduced root senescence,which is associated with an increased post-silking N *** showed that post-silking N uptake,DMA,and grain yield in summer maize were negatively correlated with the kernel position *** conclusion,the combined application of

关键词： chemical fertilizer dry mater accumulation kernel position effect N uptake organic fertilizer

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

ALTERNATING OPTIMIZATION METHOD FOR ISOGEOMETRIC TOPOLOGY OPTIMIZATION WITH STRESS CONSTRAINTS

引用

Journal of Computational Mathematics 2024年第1期42卷 134-155页

作者： Xiaoya zhai School of Mathematical Sciences University of Science and Technology of ChinaHefei 230071China

Topology optimization (TO) has developed rapidly recently. However, topology optimization with stress constraints still faces many challenges due to its highly non-linear properties which will cause inefficient computation, iterative oscillation, and convergence guarantee problems. At the same time, isogeometric analysis (IGA) is accepted by more and more researchers, and it has become one important tool in the field of topology optimization because of its high fidelity. In this paper, we focus on topology optimization with stress constraints based on isogeometric analysis to improve computation efficiency and stability. A new hybrid solver combining the alternating direction method of multipliers and the method of moving asymptotes (ADMM-MMA) is proposed to solve this problem. We first generate an initial feasible point by alternating direction method of multipliers (ADMM) in virtue of the rapid initial descent property. After that, we adopt the method of moving asymptotes (MMA) to get the final results. Several benchmark examples are used to verify the proposed method, and the results show its feasibility and effectiveness.

关键词： Isogeometric topology optimization Stress constraints The ADMM-MMA solver

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Risk factors,prognostic factors,and nomograms for distant metastasis in patients with diagnosed duodenal cancer:A population-based study

引用

World Journal of Gastrointestinal Oncology 2024年第4期16卷 1384-1420页

作者： jia-Rong Shang Chen-Yi Xu Xiao-Xue zhai Zhe Xu Jun Qian Department of Oncology Jiangsu Province Hospital of Chinese MedicineThe Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210000Jiangsu ProvinceChina Department of Proctology Nanjing Hospital of Chinese MedicineNanjing 210000Jiangsu ProvinceChina Department of Digestive Cancer Surgery Jiangsu Province Hospital of Chinese MedicineThe Affiliated Hospital of Nanjing University of Chinese MedicineNanjing 210000Jiangsu ProvinceChina

BACKGROUND Duodenal cancer is one of the most common subtypes of small intestinal cancer,and distant metastasis(DM)in this type of cancer still leads to poor *** nomograms have recently been used in tumor areas,no studies have focused on the diagnostic and prognostic evaluation of DM in patients with primary duodenal *** To develop and evaluate nomograms for predicting the risk of DM and person-alized prognosis in patients with duodenal *** Data on duodenal cancer patients diagnosed between 2010 and 2019 were extracted from the Surveillance,Epidemiology,and End Results *** and multivariate logistic regression analyses were used to identify independent risk factors for DM in patients with duodenal cancer,and univariate and multivariate Cox proportional hazards regression analyses were used to determine independent prognostic factors in duodenal cancer patients with *** novel nomograms were established,and the results were evaluated by receiver operating characteristic(ROC)curves,calibration curves,and decision curve analysis(DCA).RESULTS A total of 2603 patients with duodenal cancer were included,of whom 457 cases(17.56%)had DM at the time of *** analysis revealed independent risk factors for DM in duodenal cancer patients,including gender,grade,tumor size,T stage,and N stage(P<0.05).Univariate and multivariate COX analyses further identified independent prognostic factors for duodenal cancer patients with DM,including age,histological type,T stage,tumor grade,tumor size,bone metastasis,chemotherapy,and surgery(P<0.05).The accuracy of the nomograms was validated in the training set,validation set,and expanded testing set using ROC curves,calibration curves,and DCA *** results of Kaplan-Meier survival curves(P<0.001)indicated that both nomograms accurately predicted the occurrence and prognosis of DM in patients with duodenal *** The two nomograms are expected as effective tools fo

关键词： Duodenal cancer Distant metastasis Nomogram Risk factors Prognostic factors

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Multi-Objective Optimization of the Ultrasonic Scalpel Rod and Tip with Improved Performance:Vibration Frequency,Amplitude,and Service Life

引用

Chinese Journal of Mechanical Engineering 2024年第4期37卷 107-119页

作者： jiaqi Zhao Yuhao zhai Xuzhe jia Naiwen Deng Kunxu Li Guangchao Han Rong Chen Dong Wang Wei Bai School of Mechanical Engineering and Electronic Information China University of GeosciencesWuhan 430074China Shenzhen Research Institute China University of GeosciencesShenzhen 518057China College of Engineering Mathematics and Physical SciencesUniversity of ExeterExeter EX44QFUK Shenzhen Huazhong University of Science and Technology Research Institute Shenzhen 518000China

Ultrasonic scalpel design for minimally invasive surgical procedures is mainly focused on optimizing cutting ***,an important issue is the low fatigue life of traditional ultrasonic scalpels,which affects their long-term reliability and effectiveness and creates hidden dangers for *** this study,a multi-objective optimal design for the cutting performance and fatigue life of ultrasonic scalpels was proposed using finite element analysis and fatigue *** optimal design parameters of resonance frequency and amplitude were *** setting the transition fillet and keeping the gain structure away from the node position to enable the scalpel to have a high service life with excellent cutting *** frequency modulation method of setting the vibration node bosses at the node position and setting the vibration antinode grooves at the antinode position was ***,the mechanism of the influence of various design elements,such as tip,shank,node position,and antinode position,on the resonance frequency,amplitude,and fatigue life of the ultrasonic scalpel was analyzed,and the optimal design principles of the ultrasonic scalpel were *** proposed ultrasonic scalpel design was confirmed by simulations,impedance measurements,and liver tissue cutting experiments,demonstrating its feasibility and enhanced *** research introduces innovative design strategies to improve the fatigue life and performance of ultrasonic scalpels to address an important issue in minimally invasive surgery.

关键词： Multi-objective optimal design Minimally invasive surgical procedures Service life Ultrasonic scalpel

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Phomaketals A and B,pentacyclic meroterpenoids from a eupC overexpressed mutant strain of Phoma sp.

引用

Chinese Chemical Letters 2024年第7期35卷 350-354页

作者： Chuan Li Yangyang Han Yanan zhai Ke Li Xingzhong Liu Zhuan Zhang Cai jia Yongsheng Che NHC Key Laboratory of Biotechnology of Antibiotics Institute of Medicinal BiotechnologyChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China State Key Laboratory of Toxicology&Medical Countermeasures Beijing Institute of Pharmacology&ToxicologyBeijing 100850China Department of Microbiology College of Life SciencesNankai UniversityTianjin 300071China

Phomaketals A(1)and B(2),two tropolonic meroterpenoids with the unprecedented pentacyclic skeletons,were isolated from the solid-substrate fermentation cultures of a eupC overexpressed mutant strain of the fungus Phoma sp.,together with a biogenetically related secondary metabolite pughiinin B(3),and the known one noreupenifeldin B(4).The structures of 1–3 were elucidated primarily by nuclear magnetic resonance(NMR)*** absolute configurations of 1 and 2 were assigned by electronic circular dichroism calculations and the calculated NMR with DP4+analysis,while that of 3 was established by single-crystal X-ray diffraction analysis using Cu Kα***,phomaketals A(1)and B(2)could be derived from the hypothetical tropolonic sesquiterpene intermediates neosetophomone B(6)and 9-R-neosetophomone B(6),respectively,via different reactions *** 1 showed antiproliferative effect only against the SUPB15 cells,with an 50%inhibitory concentration(IC50)value of 4.85μmol/L,while the co-isolated known meroterpenoid 4 displayed potent effects against three tumor cell lines,SUPB15,EL4,and H9,showing IC50values of 0.36–27.08μmol/L.

关键词： Phoma sp. Tropolonic sesquiterpenes Biosynthetic pathways Hetero-Diels–Alder Cytotoxicity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effect of Low-temperature Imidization on Properties and Aggregation Structures of Polyimide Films with Different Rigidity

引用

Chinese Journal of Polymer Science 2024年第8期42卷 1134-1146页

作者： Yan jia Lei zhai Song Mo Yi Liu Li-Xin Liu Xin-Yu Du Min-Hui He Lin Fan Key Laboratory of Science and Technology on High-tech Polymer Materials Institute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China

The traditional high-temperature preparation process of polyimide can cause many problems and limits the wider application in extreme *** important challenge to be solved urgently is the reduction of imidization *** this work,twelve kinds of polyimide films with different chain rigidity were prepared at low temperature of 200℃,in the absence or presence of imidazole used as the *** molecular rigidity and free volume were theoretically calculated,and relationship between structure and properties were systematically *** results show that imidization reaction under low temperatures is significantly affected by the rigidity of molecula r *** rigid structure of polyimide is not conducive to the low-temperature imidization,but this adverse effect can be eliminated by adding catalyst,resulting the notably increased imidization *** optical and thermal properties can be improved to a certain extent for the chemically catalyzed system,resulting in relatively higher heat resistance and thermal *** the mechanical performance could be determined by com plicating factors,greatly different from polyimide films prepa red by high temperature *** investigate aggregation structures of film s,the effect of chain rigidity and catalyst on the stacking or orientation of molecular chains was further *** wo rk can contribute to the understanding of chemically catalyzed imidization that is rarely reported in the existing research,and will provide guidance for the low-temperature preparation of high-performance polyimides.

关键词： Polyimide Imidization Catalyst Structure and properties Aggregation structures

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：