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Safety and efficacy of modified endoscopic ultrasound-guided selective N-butyl-2-cyanoacrylate injections for gastric variceal hemorrhage in left-sided portal hypertension
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作者 yan zeng Jian yang Jun-Wen Zhang 《World Journal of Gastrointestinal Endoscopy》 2024年第1期29-36,共8页
BACKGROUND Gastric variceal hemorrhage is one of the primary manifestations of left-sided portal hypertension(LSPH).The hemorrhage is fatal and requires safe and effective interventions.AIM To evaluate the clinical sa... BACKGROUND Gastric variceal hemorrhage is one of the primary manifestations of left-sided portal hypertension(LSPH).The hemorrhage is fatal and requires safe and effective interventions.AIM To evaluate the clinical safety and efficacy of modified endoscopic ultrasound(EUS)-guided selective N-butyl-2-cyanoacrylate(NBC)injections for gastric variceal hemorrhage in LSPH.METHODS A retrospective observational study of patients with LSPH-induced gastric variceal hemorrhage was conducted.Preoperative EUS evaluations were performed.Enrolled patients were divided into modified and conventional groups according to the NBC injection technique.The final selection of NBC injection technique depended on the patients’preferences and clinical status.The technical and clinical success rates,operation time,NBC doses,perioperative complications,postoperative hospital stay,and recurrent bleeding rates were analyzed,respectively.RESULTS A total of 27 patients were enrolled.No statistically significant differences were observed between the two groups regarding baseline characteristics.In comparison to patients in the conventional group,patients in the modified group demonstrated significantly reduced NBC doses(2.0±0.6 mL vs 3.1±1.0 mL;P=0.004)and increased endoscopic operation time(71.9±11.9 min vs 22.5±6.7 min;P<0.001).Meanwhile,the two groups had no significant difference in the technical and clinical success rates,perioperative complications,postoperative hospital stay,and recurrent bleeding rates.CONCLUSION Modified EUS-guided selective NBC injections demonstrated safety and efficacy for LSPH-induced gastric variceal hemorrhage,with advantages of reduced injection dose and no radiation risk.Drawbacks were time consumption and technical challenge. 展开更多
关键词 Endoscopic ultrasound SELECTIVE N-butyl-2-cyanoacrylate Gastric varices Hemorrhage Left-sided portal hypertension
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Brain region-specific roles of brain-derived neurotrophic factor in social stress-induced depressive-like behavior 被引量:3
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作者 Man Han Deyang zeng +7 位作者 Wei Tan Xingxing Chen Shuyuan Bai Qiong Wu Yushan Chen Zhen Wei Yufei Mei yan zeng 《Neural Regeneration Research》 SCIE CAS 2025年第1期159-173,共15页
Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral response.Recent studies have shown that brain-derived neurotrophic factor expression in stressed mice ... Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral response.Recent studies have shown that brain-derived neurotrophic factor expression in stressed mice is brain region–specific,particularly involving the corticolimbic system,including the ventral tegmental area,nucleus accumbens,prefrontal cortex,amygdala,and hippocampus.Determining how brain-derived neurotrophic factor participates in stress processing in different brain regions will deepen our understanding of social stress psychopathology.In this review,we discuss the expression and regulation of brain-derived neurotrophic factor in stress-sensitive brain regions closely related to the pathophysiology of depression.We focused on associated molecular pathways and neural circuits,with special attention to the brain-derived neurotrophic factor–tropomyosin receptor kinase B signaling pathway and the ventral tegmental area–nucleus accumbens dopamine circuit.We determined that stress-induced alterations in brain-derived neurotrophic factor levels are likely related to the nature,severity,and duration of stress,especially in the above-mentioned brain regions of the corticolimbic system.Therefore,BDNF might be a biological indicator regulating stress-related processes in various brain regions. 展开更多
关键词 AMYGDALA chronic mild stress chronic social defeat stress corticolimbic system DEPRESSION HIPPOCAMPUS medial prefrontal cortex nucleus accumbens social stress models ventral tegmental area
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Glucocorticoid receptor signaling in the brain and its involvement in cognitive function 被引量:1
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作者 Chonglin Su Taiqi Huang +3 位作者 Meiyu Zhang yanyu Zhang yan zeng Xingxing Chen 《Neural Regeneration Research》 SCIE CAS 2025年第9期2520-2537,共18页
The hypothalamic-pituitary-adrenal axis regulates the secretion of glucoco rticoids in response to environmental challenges.In the brain,a nuclear receptor transcription fa ctor,the glucocorticoid recepto r,is an impo... The hypothalamic-pituitary-adrenal axis regulates the secretion of glucoco rticoids in response to environmental challenges.In the brain,a nuclear receptor transcription fa ctor,the glucocorticoid recepto r,is an important component of the hypothalamicpituitary-a d renal axis's negative feedback loop and plays a key role in regulating cognitive equilibrium and neuroplasticity.The glucoco rticoid receptor influences cognitive processes,including glutamate neurotransmission,calcium signaling,and the activation of brain-derived neurotrophic factor-mediated pathways,through a combination of genomic and non-genomic mechanisms.Protein interactions within the central nervous system can alter the expression and activity of the glucocorticoid receptor,there by affecting the hypothalamic-pituitary-a d renal axis and stress-related cognitive functions.An appropriate level of glucocorticoid receptor expression can improve cognitive function,while excessive glucocorticoid receptors or long-term exposure to glucoco rticoids may lead to cognitive impairment.Patients with cognitive impairment-associated diseases,such as Alzheimer's disease,aging,depression,Parkinson's disease,Huntington's disease,stroke,and addiction,often present with dysregulation of the hypothalamic-pituitary-adrenal axis and glucocorticoid receptor expression.This review provides a comprehensive overview of the functions of the glucoco rticoid receptor in the hypothalamic-pituitary-a d renal axis and cognitive activities.It emphasizes that appropriate glucocorticoid receptor signaling fa cilitates learning and memory,while its dysregulation can lead to cognitive impairment.This provides clues about how glucocorticoid receptor signaling can be targeted to ove rcome cognitive disability-related disorders. 展开更多
关键词 brain-derived neurotrophic factor calcium signaling glucocorticoid receptor GLUCOCORTICOID glutamate transmission hypothalamic-pituitary-adrenal axis long-term potentiation neurocognitive disorders NEUROPLASTICITY stress
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Endoscopic management of infected necrotizing pancreatitis:Advancing through standardization 被引量:2
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作者 yan zeng Jun-Wen Zhang Jian yang 《World Journal of Gastroenterology》 2025年第20期18-31,共14页
Infected necrotizing pancreatitis(INP)remains a life-threatening complication of acute pancreatitis.Despite advancements such as endoscopic ultrasound(EUS)-guided drainage,lumen-apposing metal stents,and protocolized ... Infected necrotizing pancreatitis(INP)remains a life-threatening complication of acute pancreatitis.Despite advancements such as endoscopic ultrasound(EUS)-guided drainage,lumen-apposing metal stents,and protocolized step-up strate-gies,the clinical practice remains heterogeneous,with variability in endoscopic strategies,procedural timing,device selection,and adjunctive techniques contri-buting to inconsistent outcomes.This review synthesizes current evidence to contribute to a structured framework integrating multidisciplinary team decision-making,advanced imaging(three-dimensional reconstruction,contrast-enhanced computed tomography/magnetic resonance imaging),EUS assessment,and biomarker-driven risk stratification(C-reactive protein,procalcitonin)to optimize patient selection,intervention timing,and complication management.Key stan-dardization components include endoscopic assessment and procedural strate-gies,optimal timing of intervention,personalized approaches for complex pan-creatic collections,and techniques to reduce the number of endoscopic debride-ments and mitigate complications.This work aims to enhance clinical outcomes,minimize practice heterogeneity,and establish a foundation for future research and guideline development in endoscopic management of INP. 展开更多
关键词 Infected necrotizing pancreatitis Endoscopic management Perioperative management Standardized management Multidisciplinary collaboration
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Endoscopic management of pancreatic cystic neoplasms
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作者 yan zeng Jun-Wen Zhang Jian yang 《World Journal of Gastrointestinal Oncology》 2025年第9期39-53,共15页
Pancreatic cystic neoplasms(PCNs)represent a spectrum of heterogeneous lesions with diverse biological behaviors and malignant potential.This category encompasses relatively common subtypes,such as intraductal papilla... Pancreatic cystic neoplasms(PCNs)represent a spectrum of heterogeneous lesions with diverse biological behaviors and malignant potential.This category encompasses relatively common subtypes,such as intraductal papillary mucinous neoplasms,serous cystic neoplasms,and mucinous cystic neoplasms,alongside relatively rarer entities,including cystic degeneration of solid pancreatic tumors.The widespread use of cross-sectional imaging has led to increased incidental detection of PCNs,subsequently driving a surge in PCN-related medical consultations and interventions;thus,standardized management of PCNs demands heightened attention.Continuous advancements in endoscopic techno-logies,particularly endoscopic ultrasound(EUS)and EUS-guided procedures,now offer diversified diagnostic and therapeutic options,establishing EUS as a pivotal tool for diagnosing,surveillance,and treating PCNs.This review synthesizes current evidence and evolving clinical practices in the endoscopic management of PCNs,emphasizing optimizing preoperative diagnostic accuracy,standardizing endoscopic protocols,implementing subtype-specific risk strati-fication,promoting multidisciplinary team approaches,and addressing challenges in emerging technologies. 展开更多
关键词 Pancreatic cystic neoplasms Endoscopic management Endoscopic ultrasound Endoscopic retrograde cholangiopancreatography Risk stratification Multidisciplinary team
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Attention to cancer-related physical and mental fatigue:Breaking the vicious cycle
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作者 yan zeng Jun-Wen Zhang Jian yang 《World Journal of Psychiatry》 2025年第3期1-7,共7页
Cancer-related fatigue(CRF)presents as a complex interplay between physical and mental fatigue,with mindfulness interventions offering a promising approach to alleviate both.These techniques,including mindfulness-base... Cancer-related fatigue(CRF)presents as a complex interplay between physical and mental fatigue,with mindfulness interventions offering a promising approach to alleviate both.These techniques,including mindfulness-based stress reduction,cognitive therapy,dialectical behavior therapy,and acceptance and commitment therapy,are designed to break the cycle of CRF by addressing its psychological and emotional aspects.This editorial integrates the latest research published by Liu et al,examining the reciprocal and harmful cyclical relationship between physical and mental CRF,and explores the causes and associated mindfulness interventions.We expect that future research will emphasize the identification and management of CRF,particularly focusing on the application of various mindfulness interventions in cancer survivors and patients undergoing cancer treatment,as well as the development of mindfulness in the era of new technologies. 展开更多
关键词 Cancer-related fatigue Physical fatigue Mental fatigue MINDFULNESS Mindfulness interventions Cancer management
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Natural products for the treatment of age-related macular degeneration:New insights focusing on mitochondrial quality control and cGAS/STING pathway
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作者 Xuelu Xie Shan Lian +6 位作者 Wenyong yang Sheng He Jingqiu He Yuke Wang yan zeng Fang Lu Jingwen Jiang 《Journal of Pharmaceutical Analysis》 2025年第5期956-973,共18页
Age-related macular degeneration(AMD)is a disease that affects the vision of elderly individuals worldwide.Although current therapeutics have shown effectiveness against AMD,some patients may remain unresponsive and c... Age-related macular degeneration(AMD)is a disease that affects the vision of elderly individuals worldwide.Although current therapeutics have shown effectiveness against AMD,some patients may remain unresponsive and continue to experience disease progression.Therefore,in-depth knowledge of the mechanism underlying AMD pathogenesis is urgently required to identify potential drug targets for AMD treatment.Recently,studies have suggested that dysfunction of mitochondria can lead to the aggregation of reactive oxygen species(ROS)and activation of the cyclic GMP-AMP synthase(cGAS)/stimulator of interferon genes(STING)innate immunity pathways,ultimately resulting in sterile inflammation and cell death in various cells,such as cardiomyocytes and macrophages.Therefore,combining strategies targeting mitochondrial dysfunction and inflammatory mediators may hold great potential in facilitating AMD management.Notably,emerging evidence indicates that natural products targeting mitochondrial quality control(MQC)and the cGAS/STING innate immunity pathways exhibit promise in treating AMD.Here,we summarize phytochemicals that could directly or indirectly influence the MQC and the cGAS/STING innate immunity pathways,as well as their interconnected mediators,which have the potential to mitigate oxidative stress and suppress excessive inflammatory responses,thereby hoping to offer new insights into therapeutic interventions for AMD treatment. 展开更多
关键词 Age-related macular degeneration PHYTOCHEMICALS Mitochondrial quality control MITOPHAGY Mitochondrial biogenesis cGAS/STING
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Accessing Elastic Properties of Porous Solid Oxide Fuel Cell Electrodes Using 2D Image-Based Discrete Element Modeling and Deep Learning
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作者 Shihao Zhou yan zeng +6 位作者 Xuhao Liu Xianhang Li Christophe L.Martin Naoki Shikazono Shotaro Hara Zilin yan Zheng Zhong 《Acta Mechanica Solida Sinica》 2025年第3期384-401,共18页
The mechanical properties of solid oxide fuel cells(SOFCs)can limit their mechanical stability and lifespan.Understanding the correlation between the microstructure and mechanical properties of porous electrode is ess... The mechanical properties of solid oxide fuel cells(SOFCs)can limit their mechanical stability and lifespan.Understanding the correlation between the microstructure and mechanical properties of porous electrode is essential for enhancing the performance and durability of SOFCs.Accurate prediction of mechanical properties of porous electrode can be achieved by microscale finite element modeling based on three-dimensional(3D)microstructures,which requires expensive 3D tomography techniques and massive computational resources.In this study,we proposed a cost-effective alternative approach to access the mechanical properties of porous electrodes,with the elastic properties of La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δc)athode serving as a case study.Firstly,a stochastic modeling was used to reconstruct 3D microstructures from two-dimensional(2D)cross-sections as an alternative to expensive tomography.Then,the discrete element method(DEM)was used to predict the elastic properties of porous ceramics based on the discretized 3D microstructures reconstructed by stochastic modeling.Based on 2D microstructure and the elastic properties calculated by the DEM modeling of the 3D reconstructed porous microstructures,a convolutional neural network(CNN)based deep learning model was built to predict the elastic properties rapidly from 2D microstructures.The proposed combined framework can be implemented with limited computational resources and provide a basis for rapid prediction of mechanical properties and parameter estimation for multiscale modeling of SOFCs. 展开更多
关键词 Porous ceramics MICROSTRUCTURE Stochastic reconstruction Discrete element method Deep learning
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高原官兵高压氧治疗的探讨——临床应用、护理策略与展望
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作者 曾艳 冯正勇 +2 位作者 路俊霞 潘露露 牛爱芳 《医学研究前沿》 2025年第11期87-89,共3页
高原环境低氧、低温、低气压,长期驻留或执行任务的官兵易发生急性高原病、慢性高原损伤及创伤后缺氧性并发症,威胁身心健康与战斗力。高压氧治疗(HBOT)可快速提升血氧分压、增加组织氧供,是防治缺氧相关疾病的重要手段。本文梳理其临... 高原环境低氧、低温、低气压,长期驻留或执行任务的官兵易发生急性高原病、慢性高原损伤及创伤后缺氧性并发症,威胁身心健康与战斗力。高压氧治疗(HBOT)可快速提升血氧分压、增加组织氧供,是防治缺氧相关疾病的重要手段。本文梳理其临床应用场景,总结全周期护理策略,展望未来研究方向,为提升高原官兵医疗保障水平提供参考。 展开更多
关键词 高原官兵 高压氧治疗 临床应用 护理策略 高原病
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水淹胁迫对美洲黑杨嫁接苗叶片色素及光合特性的影响 被引量:1
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作者 张江涛 杨淑红 +3 位作者 晏增 马永涛 赵蓬晖 朱延林 《上海农业学报》 2024年第4期44-50,共7页
以‘全红杨’‘中红杨’和‘2025杨'3个品种嫁接苗为试验材料,采用随机区组设计,盆栽模拟水淹环境,以正常浇水条件为对照,研究不同胁迫处理时间下,3个杨树品种的叶片色素含量、光合特性的响应变化及各指标间的相关性。结果表明:水... 以‘全红杨’‘中红杨’和‘2025杨'3个品种嫁接苗为试验材料,采用随机区组设计,盆栽模拟水淹环境,以正常浇水条件为对照,研究不同胁迫处理时间下,3个杨树品种的叶片色素含量、光合特性的响应变化及各指标间的相关性。结果表明:水淹胁迫期间,3个杨树品种叶片色素含量及气孔导度(G_(s))、净光合速率(P_(n))、蒸腾速率(T_(r))和胞间CO_(2)浓度(C_(i))均极显著下降。胁迫后期,叶绿素a含量下降幅度大于叶绿素b,同时叶片C_(i)升高,羧化效率(CE)下降,C_(i)与P_(n)的相关性由正变为负,三者P_(n)的再次下降主要是由非气孔限制所致。对P_(n)的相关性分析表明,花色素苷含量与‘全红杨’叶片P_(n)呈正相关,而‘2025杨’花色素苷含量与P_(n)呈负相关。水淹胁迫70d,3个杨树品种叶片P_(n)均始终为正值,水分利用效率(WUE)大幅提高,表现出稳定的耐涝遗传特质,其中‘全红杨'耐水淹能力相对较弱。 展开更多
关键词 杨树品种 水淹胁迫 色素含量 光合特性 相关性分析 耐涝性
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Mesozoic Thrust-Nappe and Extensional Structure Frameworks in the East Segment of Southeast Yangtze Block, Southeast China 被引量:3
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作者 Xinqi Yu Ziwei Chen +5 位作者 Jun Hu yan zeng Xiu Liu Yu He Zishen Wang Linghui Meng 《Journal of Earth Science》 SCIE CAS CSCD 2020年第4期772-794,共23页
Multi-stage Mesozoic thrust-nappe and extensional structures are distributed in the east segment of the Southeast Yangtze Block situated in the junction region of Zhejiang-Jiangxi-Anhui provinces. The features and gen... Multi-stage Mesozoic thrust-nappe and extensional structures are distributed in the east segment of the Southeast Yangtze Block situated in the junction region of Zhejiang-Jiangxi-Anhui provinces. The features and genetic mechanism of the deformations were analyzed after a detailed field observation of their distribution, geometry, and kinematics. In addition, the time sequences of the thrust and extensional structures were determined by combining the results of the comparative analysis with the chronological evidence of strata and magmatic rocks cut by a fault or formed after a fault according to field facts. This study identified three stages of the nappe structures and at least two stages of the extensional structures during the Mesozoic. The geotectonic setting of the nappe and extensional structures was considered to be related to the different geodynamics in the study area including the Early Mesozoic geological event, i.e., N-S compression, forming Lantian fault, etc.;the Late Mesozoic flat-slab subduction, forming Xiaoxi thrust fault and tectonic window;and the roll-back of the paleoPacific Plate, forming extensional structures like basin marginal fault;the last compression, forming Wucheng-Shenxian fault. These findings provide additional evidence for remodeling the tectonic and geodynamic evolution of Southeast China. 展开更多
关键词 MESOZOIC nappe structure extensional structure time sequence east segment of the Southeast Yangtze Block
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Modified endoscopic ultrasound-guided selective N-butyl-2-cyanoacrylate injections for gastric variceal hemorrhage in left-sided portal hypertension:A case report 被引量:3
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作者 Jian yang yan zeng Jun-Wen Zhang 《World Journal of Clinical Cases》 SCIE 2022年第18期6254-6260,共7页
BACKGROUND Left-sided portal hypertension(LSPH),also known as sinistral portal hypertension or regional portal hypertension,refers to extrahepatic portal hypertension caused by splenic vein obstruction or stenosis.N-b... BACKGROUND Left-sided portal hypertension(LSPH),also known as sinistral portal hypertension or regional portal hypertension,refers to extrahepatic portal hypertension caused by splenic vein obstruction or stenosis.N-butyl-2-cyanoacrylate(NBC)has been widely used in the endoscopic hemostasis of portal hypertension,but adverse events including renal or pulmonary thromboembolism,mucosal necrosis and gastrointestinal(GI)bleeding may occur after treatment.Herein,we report successfully managing gastric variceal(GV)hemorrhage secondary to LSPH using modified endoscopic ultrasound(EUS)-guided selective NBC injections.CASE SUMMARY A 35-year-old man was referred to our hospital due to an upper GI hemorrhage.Gastroscopy revealed GV hemorrhage and computed tomography venography(CTV)confirmed LSPH.The patient requested endoscopic procedures and rejected surgical therapies including splenectomy.EUS-guided selective NBC injections were performed and confluences of gastric varices were selected as the injection sites to reduce the injection dose.The“sandwich”method using undiluted NBC and hypertonic glucose was applied.No complications occurred.The patient was followed up regularly after discharge.Three months later,the follow-up gastroscopy revealed firm gastric submucosa with no sign of NBC expulsion and the follow-up CTV showed improvements in LSPH.No recurrent GI hemorrhage was reported during this follow-up period.CONCLUSION EUS-guided selective NBC injection may represent an effective and economical treatment for GV hemorrhage in patients with LSPH. 展开更多
关键词 Left-sided portal hypertension Endoscopic ultrasound SELECTIVE N-butyl-2-cyanoacrylate Gastric varices Case report
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金丝楸无性系幼苗的光合生理特性比较
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作者 张江涛 晏增 +1 位作者 马永涛 赵蓬晖 《河南林业科技》 2024年第4期43-45,共3页
对7个金丝楸无性系的幼苗主要光合生理指标进行了研究,结果表明:7个无性系的光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)之间差异明显,日变化曲线依据变化趋势,可分为4种类型。蒸腾速率与气孔导度日变化趋势相同,呈正相关。
关键词 金丝楸 光合速率 蒸腾速率 气孔导度
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RUSLE模型对黄土高原退耕植被恢复坡面土壤侵蚀的模拟效果分析 被引量:8
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作者 廖俊 焦菊英 +2 位作者 严增 李建军 张世杰 《水土保持学报》 CSCD 北大核心 2024年第2期97-108,共12页
[目的]为了探究RUSLE模型对黄土高原退耕植被恢复坡面土壤侵蚀模拟的效果。[方法]基于陕北安塞区坊塌小流域内10个径流小区2016-2022年的降雨产流产沙监测资料,通过RUSLE模型中各因子在黄土高原的不同常用算法之间的变换组合,模拟144种... [目的]为了探究RUSLE模型对黄土高原退耕植被恢复坡面土壤侵蚀模拟的效果。[方法]基于陕北安塞区坊塌小流域内10个径流小区2016-2022年的降雨产流产沙监测资料,通过RUSLE模型中各因子在黄土高原的不同常用算法之间的变换组合,模拟144种因子组合下各退耕植被恢复坡面的土壤侵蚀量,采用纳什效率系数(NSE)和均方根误差(RMSE)评价模型模拟结果的有效性。[结果]利用RUSLE模型144种因子组合模拟的退耕植被恢复坡面土壤侵蚀量,NSE范围为-38.47~0.19,RMSE范围为1.92~12.65 t/(hm 2·a),模拟效果较差,所选各因子算法难以适应退耕植被恢复坡面上的土壤流失量的评估,还需要对RUSLE模型各因子进一步改进。运用RUSLE模型对黄土高原退耕植被恢复坡面土壤侵蚀模拟时,建议尽可能采用时间分辨率高的数据减小对R因子的计算误差,综合考虑土壤有机质含量、土壤粒径与团粒结构组成和容重等土壤理化性质对K因子的影响,以及植被覆盖度、植被高度、枯落物、生物结皮等对C因子的影响,充分考虑10°以上的坡度,细化其LS因子的算法。[结论]RUSLE模型无法很好地适用于黄土高原退耕植被恢复坡面土壤侵蚀的模拟。研究结果为土壤侵蚀模型的研发及RUSLE模型在黄土高原植被恢复坡面的应用提供一定参考依据。 展开更多
关键词 RUSLE模型 土壤侵蚀 退耕坡面 植被恢复 径流小区 黄土高原
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为野生植物保护和可持续贸易奠定科学基础——CITES植物委员会第27次会议评述 被引量:1
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作者 何拓 曾岩 +4 位作者 殷亚方 张坤 袁良琛 董晖 周志华 《生物多样性》 CAS CSCD 北大核心 2024年第9期167-171,共5页
《濒危野生动植物种国际贸易公约》(CITES)植物委员会第27次会议(PC27)于2024年7月8-13日在瑞士日内瓦召开,来自全球46个缔约方和30个观察员组织的190名代表出席会议。本次会议共有42项议题,讨论了即将向CITES第二十次缔约方大会(Co P20... 《濒危野生动植物种国际贸易公约》(CITES)植物委员会第27次会议(PC27)于2024年7月8-13日在瑞士日内瓦召开,来自全球46个缔约方和30个观察员组织的190名代表出席会议。本次会议共有42项议题,讨论了即将向CITES第二十次缔约方大会(Co P20)提交讨论的决议、决定和其他事项执行进展情况。PC27反映了各方为确保野生植物可持续国际贸易作出的一致努力,促进了各方在CITES科学和技术问题上的国际合作和能力建设,也呈现出CITES与《生物多样性公约》加强协同合作,不断拓展其职责范围,以及科学性逐渐减弱等特点。为更加有效地履行CITES,我国应夯实濒危物种履约科学基础,提升非致危性判定研究水平,建立履约人才队伍,推动野生植物科学保护和可持续利用。 展开更多
关键词 CITES 国际贸易 物种保护 可持续利用
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黄土丘陵沟壑区坡沟系统产流产沙对源-汇-路径格局的响应 被引量:1
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作者 严增 焦菊英 +11 位作者 唐柄哲 曹斌挺 李航 梁越 祁泓锟 廖俊 徐倩 严晰芹 李萌萌 姜晓晗 张子琦 李建军 《农业工程学报》 EI CAS CSCD 北大核心 2024年第5期118-127,共10页
坡沟系统是流域水土流失与治理的基本单元,掌握其产流产沙规律是有效解决水土流失区生态环境恢复重建的核心问题之一。该研究利用无人机遥感与地理信息系统技术对流域的土地利用进行识别,再确定5个不同坡沟系统(2个无人为干扰的退耕植... 坡沟系统是流域水土流失与治理的基本单元,掌握其产流产沙规律是有效解决水土流失区生态环境恢复重建的核心问题之一。该研究利用无人机遥感与地理信息系统技术对流域的土地利用进行识别,再确定5个不同坡沟系统(2个无人为干扰的退耕植被恢复+自然植被坡沟系统SG1和SG2、2个人为扰动的退耕植被恢复+自然植被坡沟系统SG3和SG4、1个果园+坡耕地的坡沟系统SG5)内泥沙源、汇及其输移路径分布特征,并在量化指标的基础上,结合2016—2022年坊塌小流域5个坡沟系统的降雨和产流产沙的监测数据,研究了不同坡沟系统的产流产沙特征及其对源-汇-路径格局的响应。结果表明:次降雨条件下,SG1和SG2的产沙模数显著低于其他坡沟系统(P<0.05),且SG3径流深和产沙模数均较大;SG2的年平均径流深显著低于SG5(P<0.05)。坡沟系统径流深分别与总坡沟系统、沟间地、沟谷地的泥沙源和汇最大斑块面积比显著正相关(P<0.05),且与沟间地泥沙源、汇指数的相关系数均要大于沟谷地,径流深与总坡沟系统路径的分岔比、沟间地与沟谷地的路径比降均呈现出显著负相关(P<0.05);产沙模数与各源汇指数之间均无显著的相关性,但与路径数量密度、长度密度、沟间地的路径分岔比呈显著正相关(P<0.05);径流深和产沙模数均与路径复杂度呈显著负相关(P<0.05)。可见,降低源/汇比例大小,适当增加泥沙输移路径的复杂度和输移距离,可有效减少坡沟系统的水土流失。研究可为坡沟系统土壤侵蚀防控以及流域生态保护和修复提供科学支撑。 展开更多
关键词 泥沙 景观 径流 坡沟系统 产流产沙 源汇 输移路径
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带侧烷基聚酯型聚氨酯的微相分离与耐湿热性能 被引量:1
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作者 曾妍 易玉华 《高分子材料科学与工程》 CSCD 北大核心 2024年第11期11-18,共8页
为了分析侧烷基对聚酯型聚氨酯(PU)耐湿热性能的影响,分别采用聚己内酯二醇(PCL220N)、聚己二酸己二醇酯二醇(CMA2066)、聚己二酸-2-丁基-2-乙基-1,3丙二醇酯二醇(PBEPG)和聚己二酸-3-甲基-1,5戊二醇酯二醇(P2010)为软段制备了PU材料。... 为了分析侧烷基对聚酯型聚氨酯(PU)耐湿热性能的影响,分别采用聚己内酯二醇(PCL220N)、聚己二酸己二醇酯二醇(CMA2066)、聚己二酸-2-丁基-2-乙基-1,3丙二醇酯二醇(PBEPG)和聚己二酸-3-甲基-1,5戊二醇酯二醇(P2010)为软段制备了PU材料。红外光谱、动态力学热分析、热重分析和水接触角分析表明,侧烷基能提高PU软硬段间微相分离程度,软段的玻璃化转变温度降低,与水的接触角增大,耐湿热性能提高。带丁基、乙基双侧烷基的PBEPG-PU,其软段和硬段各自形成微区,观察到2个tanδ峰,微相分离程度高,拉伸强度为22.2 MPa,同时表面疏水性强,100℃,100%RH下老化36 h后拉伸强度保持率为71.2%,表现出较好的耐湿热性能和较高的力学强度。 展开更多
关键词 聚酯型聚氨酯 烷基侧基 微相分离 耐湿热性能
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Early gastric cancer recurrence after endoscopic submucosal dissection:Not to be ignored! 被引量:3
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作者 yan zeng Jian yang Jun-Wen Zhang 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第1期8-12,共5页
This editorial comments on the article“Efficacy of multi-slice spiral computed tomography in evaluating gastric cancer recurrence after endoscopic submucosal dissection”.We focus on the importance of paying more att... This editorial comments on the article“Efficacy of multi-slice spiral computed tomography in evaluating gastric cancer recurrence after endoscopic submucosal dissection”.We focus on the importance of paying more attention to postendoscopic submucosal dissection(ESD)gastric cancer recurrence in patients with early gastric cancer(EGC)and how to manage it effectively.ESD has been a wellknown treatment and the mainstay for EGC,with the advantages of less invasion and fewer complications when compared with traditional surgical procedures.Despite a lower local recurrence rate after ESD,the problem of postoperative recurrence in patients with EGC has become increasingly non-ignorable with the global popularization of ESD technology and the increasing number of post-ESD patients. 展开更多
关键词 Early gastric cancer RECURRENCE Endoscopic submucosal dissection POSTOPERATIVE PREDICTION
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Unloading and successful treatment with bioresorbable stents during percutaneous coronary intervention:A case report 被引量:2
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作者 Tao Sun Ming-Xue Zhang +7 位作者 yan zeng Li-Hua Ruan Yi Zhang Cheng-Long yang Zhang Qin Jing Wang Hai-Mei Zhu Yun Long 《World Journal of Cardiology》 2024年第8期484-490,共7页
BACKGROUND With the development of percutaneous coronary intervention(PCI),the number of interventional procedures without implantation,such as bioresorbable stents(BRS)and drug-coated balloons,has increased annually.... BACKGROUND With the development of percutaneous coronary intervention(PCI),the number of interventional procedures without implantation,such as bioresorbable stents(BRS)and drug-coated balloons,has increased annually.Metal drug-eluting stent unloading is one of the most common clinical complications.Comparatively,BRS detachment is more concealed and harmful,but has yet to be reported in clinical research.In this study,we report a case of BRS unloading and successful rescue.This is a case of a 59-year-old male with the following medical history:“Type 2 diabetes mellitus”for 2 years,maintained with metformin extended-release tablets,1 g PO BID;“hypertension”for 20 years,with long-term use of metoprolol sustained-release tablets,47.5 mg PO QD;“hyperlipidemia”for 20 years,without regular medication.He was admitted to the emergency department of our hospital due to intermittent chest pain lasting 18 hours,on February 20,2022 at 15:35.Electrocardiogram results showed sinus rhythm,ST-segment elevation in leads I and avL,and poor R-wave progression in leads V1–3.High-sensitivity troponin I level was 4.59 ng/mL,indicating an acute high lateral wall myocardial infarction.The patient’s family requested treatment with BRS,without implanta-tion.During PCI,the BRS became unloaded but was successfully rescued.The patient was followed up for 2 years;he had no episodes of angina pectoris and was in generally good condition.CONCLUSION We describe a case of a 59-year-old male experienced BRS unloading and successful rescue.By analyzing images,the causes of BRS unloading and the treatment plan are discussed to provide insights for BRS release operations.We discuss preventive measures for BRS unloading. 展开更多
关键词 Coronary artery diseases Percutaneous coronary intervention Bioresorbable stents Stent unloading Stent release Intravascular ultrasound Case report
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Post competency training in standardized training of resident physicians and integrated postgraduates 被引量:2
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作者 yan zeng Jian yang Jun-Wen Zhang 《World Journal of Clinical Cases》 SCIE 2024年第29期6250-6254,共5页
We focus on the importance and necessity of post-competency-based training in medical education alongside its current challenges and opportunities.Integrating post competency training into standardized educational fra... We focus on the importance and necessity of post-competency-based training in medical education alongside its current challenges and opportunities.Integrating post competency training into standardized educational frameworks is increasingly recognized as a critical component of preparing residents and postgraduates for real-world clinical practice.Post competency training represents a commitment to excellence in medical education,striving to produce competent,skilled practitioners to meet the challenges of modern healthcare. 展开更多
关键词 Post competency Standardized training RESIDENT POSTGRADUATE Competencybased medical education
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