检索结果-南通市图书馆

Pancreatic stent improves the success rate of needle-knife papillotomy in patients with difficult biliary cannulation

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2025年第1期31卷 58-67页

作者： Mu-Hsien Lee Cheng-Hui lin Chi-Huan Wu Yung-Kuan Tsou Kai-Feng Sung Sheng-Fu Wang nai-Jen Liu Department of Gastroenterology and Hepatology Chang Gung Memorial Hospital and Chang Gung University College of MedicineTaoyuan 33305Taiwan School of Medicine Chang Gung UniversityTaoyuan 33305Taiwan

BACKGROUND Needle-knife precut papillotomy(NKP)is typically performed ***,it remains unclear whether pancreatic stent(PS)placement can improve the outcomes of *** To explore whether PS placement improves the success rate of NKP in patients with difficult biliary *** This single-center retrospective study included 190 patients who underwent NKP between January 2017 and December 2021 after failed conventional biliary *** cases with incidental pancreatic duct cannulation during conventional biliary cannulation,the decision for pre-NKP PS placement was made at the endoscopist's *** primary outcome was the difference in the NKP success rate between patients with and without PS placement;the secondary outcome was the adverse event *** Among the 190 participants,82 received pre-NKP PS(PS-NKP group)whereas 108 did not[freehand or freehand NKP(FH-NKP)group].Post-NKP selective biliary cannulation was successful in 167(87.9%)patients,and the PS-NKP had a significantly higher success rate than the FH-NKP group(93.9%vs 83.3%,P=0.027).The overall adverse event rates were 7.3%and 11.1%in the PS-NKP and FH-NKP groups,respectively(P=0.493).A periampullary diverticulum(PAD)and significant intraoperative bleeding during NKP were independently associated with NKP failure;however,a pre-NKP PS was the only predictor of NKP *** the 44 participants with PADs,the PS-NKP group had a non-significantly higher NKP success rate than the FH-NKP group(87.5%and 65%,respectively;P=0.076).CONCLUSION PS significantly improved the success rate of NKP in patients with difficult biliary cannulation.

关键词： Difficult biliary cannulation Endoscopic retrograde cholangiopancreatography Needle-knife papillotomy Pancreatic stent Selective biliary cannulation

REGULATION OF SEDIMENTS IN SOME MEDIUM-SIZED AND SMALL RESERVOIRS ON THE HEAVILY SILT-LADEN STREAMS IN CHINA

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science in China,Ser.A 1977年第1期 89-105页

作者：张浩夏迈定陈诗基李振武夏恒斌姜乃森林斌文 Institute of Hydrotcehnical Research of Shensi Province Engineering Bureau Ministry of Water Conservancy and Electric Power

In the northern part of China, there are many streams carrying high loads of sediment, and the sedimentation in medium-sized and small reservoirs is serious. Practice has shown that for reservoirs on the said streams, it is necessary to make simultaneous regulation of sediment and water runoff, otherwise the function of runoff regulation may fail because the reservoirs may soon be abandoned due to sedimentation. Moreover, how to deal with the muddy water discharged from the reservoirs is another important problem. If it is not properly handled, serious aggradation in the river channels or reservoirs downstream may *** practice, knowledge, again practice, and again knowledge, the Chinese scientific-technical personnel and the broad masses have in close cooperation deveIoped a series of methods for tackling the problem of reservoir sedimentation. These methods consist in a rational regulation of water and sediment including the diversion of flood for irrigation and warping. This has not only slo

关键词： REGULATION OF SEDIMENTS IN SOME MEDIUM-SIZED AND SMALL RESERVOIRS ON THE HEAVILY SILT-LADEN STREAMS IN CHINA mode

Contribution of phenylpropanoid metabolism to plant development and plant–environment interactions

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Integrative Plant Biology 2021年第1期63卷 180-209页

作者： nai-Qian Dong Hong-Xuan lin National Key Laboratory of Plant Molecular Genetics CAS Centre for Excellence in Molecular Plant Sciences and Collaborative Innovation Center of Genetics and DevelopmentShanghai Institute of Plant Physiology and Ecologythe Chinese Academy of SciencesShanghai 200032China University of the Chinese Academy of Sciences Beijing 100049China School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China

Phenylpropanoid metabolism is one of the most important metabolisms in plants, yielding more than 8,000 metabolites contributing to plant development and plant-environment *** metabolism materialized during the evolution of early freshwater algae that were initiating terrestrialization and land plants have evolved multiple branches of this pathway, which give rise to metabolites including lignin, flavonoids, lignans, phenylpropanoid esters, hydroxycinnamic acid amides, and *** studies have revealed that many factors participate in the regulation of phenylpropanoid metabolism, and modulate phenylpropanoid homeostasis when plants undergo successive developmental processes and are subjected to stressful environments. In this review, we summarize recent progress on elucidating the contribution of phenylpropanoid metabolism to the coordination of plant development and plant–environment interaction, and metabolic flux redirection among diverse metabolic routes. In addition, our review focuses on the regulation of phenylpropanoid metabolism at the transcriptional, post-transcriptional, post-translational,and epigenetic levels, and in response to phytohormones and biotic and abiotic stresses.

关键词： flavonoids lignin metabolic flux phenylpropanoid secondary metabolites

Synthesis and enhanced luminescence properties of double perovskite NaLa0.95-xYxEu0.05MgWO6 phosphors

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2020年第8期39卷 895-901页

作者： Jing Zhang Jia-lin Shen nai-Cen Xu Nanjing Center China Geological SurveyNanjing 210016China Supervision and Testing Center of East China Mineral Resources of the Ministry of Land and ResourcesNanjing 210016China

Double perovskite Na(La,Y)MgWO6:Eu3+phosphors were obtained by the sol-gel method.X-ray diffractometer(XRD)patterns,scanning electron microscopy(SEM)images and photoluminescence properties were carried out to study the effect of polyethylene glycol(PEG).Enhanced optical properties were obtained by adding 3 wt%PEG under the excitation of 395 nm.Y3+with smaller radius was selected to substitute La3+in this host to decrease the symmetry and further enhance the luminescence *** Y3+concentration increasing,Na2WO4 and Y30W8O69 phases came *** emission spectra showed different shapes,and the emission intensity was enhanced by doping Y3+.Under the excitation of 395 and 465 nm,the emission intensity reached the *** Commission Internationale de L’Eclairage(CIE)coordinates of the phosphors were on the edge of the CIE diagram,illustrating that this double perovskite phosphor showed good color *** luminescence properties showed that the synthesized phosphors had great potential in solid-state lighting.

关键词： Double perovskite Structure evolution Phosphors White light emitting diodes

Populations of Ethanol Conformers in Liquid CCI4 and CS2 by Raman Spectra in OH Stretching Region

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Physics 2015年第3期28卷 245-252,I0001页

作者： nai-yin Hu Ke lin Xiao-guo Zhou Shi-lin Liu Hefei National Laboratory for Physical Sciences at the Microscale Department of Chemical PhysicsUniversity of Science and Technology of China Hefei 230025 China Synergetic Innovation Center of Quantum Information & Quantum Physics University of Science and Technology of China Hefei 230026 China

Combining Raman spectroscopy with density functional theory, the populations of the trans- and gaucheethanol conformers are investigated in carbon tetrachloride （CC14） and carbon disulfide （CS2）. The spectral contributions of two ethanol conformers are identified in OH stretching region. The energy difference between both conformers is estimated with the aid of the calculated Raman cross sections. It can be seen that the trans- ethanol is more stable in CC14 and CS2 solutions. The spectra are also obtained at different temperatures, and it is found the van＇t Hoff analysis is invalid in these solutions. By taking accounts of the Boltzmann distribution and theoretical Raman cross section, the energy difference is found to be increased with temperature, which shows the weak intermolecular interactions can enhance the population of transethanol.

关键词： Raman spectroscopy Ethanol Conformer Energy difference

Assessment of highway slope failure using neural networks

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第1期10卷 101-108页

作者： Tsung-lin LEE Hung-ming lin Yuh-pin LU 1Department of Construction and Facility Management Department of Resource and Environment Leader University

An artificial intelligence technique of back-propagation neural networks is used to assess the slope ***-site slope failure data from the South Cross-Island Highway in southern Taiwan are used to test the performance of the neural network *** numerical results demonstrate the effectiveness of artificial neural networks in the evaluation of slope failure potential based on five major factors,such as the slope gradient angle,the slope height,the cumulative precipitation,daily rainfall and strength of materials.

关键词： Neural network Prediction Highway Slope failure

Human Action Recognition Based on Dense Trajectories Analysis and Random Forest

在线全文

学校读者我要写书评

暂无评论

Journal of Electronic Science and Technology 2016年第4期14卷 370-376页

作者： pin-Zhong Pan Chung-lin Huang Sonix Technology HsinChu 30265HsinChu Department of M-Commerce and Multimedia Applications Asia UniversityTaichung 41354Taichung

This paper presents a human action recognition method. It analyzes the spatio-temporal grids along the dense trajectories and generates the histogram of oriented gradients （HOG） and histogram of optical flow （HOF） to describe the appearance and motion of the human object. Then, HOG combined with HOF is converted to bag-of-words （BoWs） by the vocabulary tree. Finally, it applies random forest to recognize the type of human action. In the experiments, KTH database and URADL database are tested for the performance evaluation. Comparing with the other approaches, we show that our approach has a better performance for the action videos with high inter-class and low inter-class variabilities.

关键词： Bag-of-words (BoWs) dense trajectories histogram of optical flow (HOF) histogram of oriented gradient (HOG) random forest vocabulary tree.

Amorphous carbon-based materials as platform for advanced highperformance anodes in lithium secondary batteries

在线全文

学校读者我要写书评

暂无评论

Nano Research 2021年第7期14卷 2053-2066页

作者： Jianwei nai Xinyue Zhao Huadong Yuan Xinyong Tao lin Guo College of Materials Science and Engineering Zhejiang University of TechnologyHangzhou 310014China School of Chemistry Beijing Advanced Innovation Center for Biomedical EngineeringBeihang UniversityBeijing 100191China

The growing concern for the exhaustion of fossil energy and the rapid revolution of electronics have created a rising demand for electrical energy storage devices with high energy density,for example,lithium secondary batteries(LSBs).With high surface area,low cost,excellent mechanical strength,and electrochemical stability,amorphous carbon-based materials(ACMs)have been widely investigated as promising platform for anode materials in the *** this review,we firstly summarize recent advances in the synthesis of the ACMs with various morphologies,ranging from zero-to three-dimensional ***,the use of ACMs in Li-ion batteries and Li metal batteries is discussed respectively with the focus on the relationship between the structural features of the as-prepared ACMs and their roles in promoting electrochemical ***,the remaining challenges and the possible prospects for the use of ACMs in the LSBs are proposed to provide some useful clews for the future developments of this attractive area.

关键词： amorphous carbon nanomaterials lithium secondary batteries energy storage

A New Type of Bistable Switching in Two-Dimensional Nonlinear Optical Superlattices

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 1996年第2期13卷 109-112页

作者： WANG Zhen-lin YANG Zhen-ju MIN nai-ben National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093

we investigate theoretically optical responsc in a two-dimensional optical superlattice with Kerr-type *** ind that in addition to the bistability reported in ***.71(1993)1003 by Xu et,al.,a new type of bista ble switching behavior *** bistability is based on the occurrence of the stop gap in the lincar spectraand the nonlinear mechanism on it,which makes switching between transmitting and non-transmitting states achievable.

关键词： Nonlinear addition nonlinear