期刊文献+
共找到613篇文章
< 1 2 31 >
每页显示 20 50 100
The Spatial-Temporal Characteristics of Meteorological Disasters in the Southwest Region of Zhejiang Province during 1953-2022
1
作者 qi zhang Yifan Wang +3 位作者 Zhidan Zhu Hongxia Shi Wenhao Yang Shujie Yuan 《Journal of Geoscience and Environment Protection》 2024年第3期16-27,共12页
Meteorological disasters are some of the most serious and costly natural disasters, which have larger effects on economic and social activity. Liuchun Lake is an ecotourism area in the southwest region of Zhejiang pro... Meteorological disasters are some of the most serious and costly natural disasters, which have larger effects on economic and social activity. Liuchun Lake is an ecotourism area in the southwest region of Zhejiang province, where also has experienced meteorological disasters including rainstorm and cold wave. Understanding the temporal-spatial characteristics of meteorological disasters is important for the local tourism and economic development. Based on the daily temperature and precipitation from 18 meteorological stations in the southwest of Zhejiang province during 1953-2022 and some statistical approaches, the temporal and spatial characteristics of meteorological disasters (Freezing, Rainstorm, Cold wave) are analyzed. The results indicate that 1) Rainstorm occurred frequently around the Liuchun lake, the frequency was about 8 times/a, it can also reach about 3 times/a in the other region. Freezing and cold wave (including strong cold wave and extremely cold wave) had the same spatial distribution as rainstorm, however, except for Liuchun lake, they occurred less than one time in the other regions;2) The trend of rainstorm had larger spatial difference, it increased in all the study area, but it increased more significantly around the study area than around Liuchun lake. Freezing was on the downtrend in the whole region, with 93.3% of the stations passed the 95% significant level. Cold wave also showed a declined trend, but it was insignificantly at most of the stations, only 33% of the stations passed the 90% significant level. Compared with cold wave, strong cold wave and extremely strong cold wave had weaker decline in all the regions. In general, from 1953 to 2022 rainstorm showed an increasing trend, it was the main meteorological disaster in the study area, cold wave displayed a decreasing trend, but it still occurred about 2 - 3 times/a in most regions. 展开更多
关键词 Southwest of Zhejiang Province RAINSTORM Cold Wave Spatial Distribution Trend Analysis
下载PDF
超高强Ti-15Mo-2.7Nb-3Al-0.2Si钛合金的强化行为及模型
2
作者 石晓辉 张琪 +3 位作者 荆镇 范智渊 刘江林 乔珺威 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第4期1136-1149,共14页
基于XRD、OM、SEM和TEM分析,研究超高强Ti-15Mo-2.7Nb-3Al-0.2Si钛合金的组织演变及强化行为。结果表明,位错强化和析出强化效应对该合金的屈服强度影响较大。冷轧+再结晶+冷轧+双时效组合工艺可获得1518 MPa的最高屈服强度,这主要归因... 基于XRD、OM、SEM和TEM分析,研究超高强Ti-15Mo-2.7Nb-3Al-0.2Si钛合金的组织演变及强化行为。结果表明,位错强化和析出强化效应对该合金的屈服强度影响较大。冷轧+再结晶+冷轧+双时效组合工艺可获得1518 MPa的最高屈服强度,这主要归因于显微组织中的高密度残存位错及密集而细小的次生α相。建立复合强化模型,其预测误差在16.6%以内。此外,研究发现次生α相体积分数的增加可以不断强化晶内区域,这使得沿晶断裂开始出现并逐渐占据整个断裂面。 展开更多
关键词 强化模型 超高强 强化行为 钛合金 Ti-15Mo-2.7Nb-3Al-0.2Si
下载PDF
苝二酰亚胺共价有机框架超级还原剂用于高效光催化芳基卤化物还原反应
3
作者 金昱丞 刘小琳 +9 位作者 曲琛 李长骏 王海龙 詹晓宁 曹昕怡 李晓锋 于宝秋 张琪 齐冬冬 姜建壮 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第2期171-183,共13页
自由基离子型分子光催化剂被证实是具有很强还原能力的可见光超级还原剂,它们在促进惰性的有机反应(例如将芳基卤化物还原为芳基自由基)方面具有突出的催化能力.然而,由于分子聚集严重地降低其催化活性,因而针对非均相超级还原剂的研究... 自由基离子型分子光催化剂被证实是具有很强还原能力的可见光超级还原剂,它们在促进惰性的有机反应(例如将芳基卤化物还原为芳基自由基)方面具有突出的催化能力.然而,由于分子聚集严重地降低其催化活性,因而针对非均相超级还原剂的研究较少.本文提出了一种新的方法来解决上述问题,通过溶剂热反应将具有连续光诱导电子转移机制的苝二亚胺超级还原剂(PDI)异质化为二维给体-受体(D-A)共价有机框架(COFs).即以N,N'-双(3-戊基)-2,5,8,11-四(4-甲酰基苯基)苝二酰亚胺(TFPDI)与1,3,6,8-四(4-氨基苯基)芘\(Py-TA)或2,3,6,7-四(4-氨基基苯基)四硫富瓦烯(TTF-TA)为原料,通过溶剂热反应分别制备了两种高晶态二维D-A型COF结构:USTB-21和USTB-22,并用于芳基氯化物、芳基溴化物和芳基碘化物的光催化还原反应.X射线衍射和理论模拟结果表明,USTB-21和USTB-22具有二维共价键连接的层状结构,分别呈现AA和AB的堆积方式.在各自最佳反应条件下,COFs显示出与均相催化剂相媲美的可见光催化性能,可高效地还原一系列芳基氯化物、芳基溴化物和芳基碘化物.其中,USTB-22在可见光驱动不同的芳香卤化物还原时,3 h内的转化率高达99%.瞬态吸收光谱结果表明,相比于均相催化剂(N,N'-双(2,6-二异丙基苯基)苝二酰亚胺),自由基阴离子激发态寿命是150 ps,USTB-21和USTB-22具有更长的激发态寿命,分别为210和260 ps.顺磁共振波谱测试结果证明,自由基阴离子光催化剂异质化成晶态D-A型COFs能够有效地促进电荷分离效率和延长激发态寿命.上述结果说明,USTB-22具有良好的光催化性能主要是因为其激发态寿命较长以及电荷分离效率较好.理论模拟结果表明,所制备的材料具有D-A型的电子结构.对COF的模型片段进行理论计算,揭示了各步反应路径中吉布斯自由能的变化,从而进一步阐明了光催化机理.在催化反应过程中,芳基卤化物还原途径可分为两个阶段:第一阶段为双光子能量输入和光驱电子转移,包括光子捕获和(TTF-PDI•−)*产生以及光驱动电子转移到4-溴苯乙酮底物;第二阶段为能量输出,用于还原4-溴苯乙酮底物生成苯乙酮.综上所述,本文通过溶剂热反应将具有连续光诱导电子转移机制的苝二亚胺超级还原剂异质化为二维D-A型COFs结构.该结构在芳基氯化物、芳基溴化物和芳基碘化物等的光催化还原反应中,可很好地促进电子从光催化剂转移到反应物,进而显著提高光催化反应的活性和选择性;本研究对于未来设计新型自由基离子型高效光催化剂提供了新的思路. 展开更多
关键词 苝酰亚胺 共价有机骨架 光催化剂 均相 芳基卤化物的还原
下载PDF
Neural stem cell-derived exosomes promote mitochondrial biogenesis and restore abnormal protein distribution in a mouse model of Alzheimer's disease
4
作者 Bo Li Yujie Chen +10 位作者 Yan Zhou Xuanran Feng Guojun Gu Shuang Han Nianhao Cheng Yawen Sun Yiming zhang Jiahui Cheng qi zhang Wei zhang Jianhui Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1593-1601,共9页
Mitochondrial dysfunction is a hallmark of Alzheimer’s disease.We previously showed that neural stem cell-derived extracellular vesicles improved mitochondrial function in the cortex of AP P/PS1 mice.Because Alzheime... Mitochondrial dysfunction is a hallmark of Alzheimer’s disease.We previously showed that neural stem cell-derived extracellular vesicles improved mitochondrial function in the cortex of AP P/PS1 mice.Because Alzheimer’s disease affects the entire brain,further research is needed to elucidate alterations in mitochondrial metabolism in the brain as a whole.Here,we investigated the expression of several important mitochondrial biogenesis-related cytokines in multiple brain regions after treatment with neural stem cell-derived exosomes and used a combination of whole brain clearing,immunostaining,and lightsheet imaging to clarify their spatial distribution.Additionally,to clarify whether the sirtuin 1(SIRT1)-related pathway plays a regulatory role in neural stem cell-de rived exosomes interfering with mitochondrial functional changes,we generated a novel nervous system-SIRT1 conditional knoc kout AP P/PS1mouse model.Our findings demonstrate that neural stem cell-de rived exosomes significantly increase SIRT1 levels,enhance the production of mitochondrial biogenesis-related fa ctors,and inhibit astrocyte activation,but do not suppress amyloid-βproduction.Thus,neural stem cell-derived exosomes may be a useful therapeutic strategy for Alzheimer’s disease that activates the SIRT1-PGC1αsignaling pathway and increases NRF1 and COXIV synthesis to improve mitochondrial biogenesis.In addition,we showed that the spatial distribution of mitochondrial biogenesis-related factors is disrupted in Alzheimer’s disease,and that neural stem cell-derived exosome treatment can reverse this effect,indicating that neural stem cell-derived exosomes promote mitochondrial biogenesis. 展开更多
关键词 Alzheimer’s disease mitochondrial biogenesis neural stem cell-derived exosome SIRT1-PGC1α regional brain distribution whole brain clearing and imaging
下载PDF
Host-induced silencing of MpPar6 confers Myzus persicae resistance in transgenic rape plants
5
作者 qi zhang Wenqin Zhan +3 位作者 Chao Li Ling Chang Yi Dong Jiang zhang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期187-194,共8页
Plant-mediated RNA interference(RNAi)has emerged as a promising technology for insect control.The green peach aphid,Myzus persicae,feeds on over 400 species of host plants.Brassica napus(rape)is the second most import... Plant-mediated RNA interference(RNAi)has emerged as a promising technology for insect control.The green peach aphid,Myzus persicae,feeds on over 400 species of host plants.Brassica napus(rape)is the second most important oilseed crop worldwide.Myzus persicae is highly reproductive and causes severe damage to the rape plants due to its quite flexible life cycle.In this study,we tested the RNAi effects of transgenic rape plants on M.persicae.By in vitro feeding M.persicae with artificial diets containing double-stranded RNAs(dsRNAs)targeting seven aphid genes,we identified a new gene encoding the partitioning-defective protein 6(Par6)as the most potent RNAi target.Tissue-and stage-expression analysis of Par6 suggested this gene is highly expressed in the embryo and adult stage of M.persicae.We next generated transgenic rape plants expressing ds Par6 by Agrobacteriummediated transformation and obtained nine independent transgenic lines.Compared to wild-type control plants,transgenic rape lines expressing ds Par6 showed strong resistance to M.persicae.Feeding assays revealed that feeding transgenic rape plants to M.persicae significantly decreased MpPar6 expression and survival rate and impaired fecundity.Furthermore,we showed that the resistance levels to M.persicae are positively correlated with ds Par6 expression levels in transgenic rape plants.Our study demonstrates that transgenic rape plants expressing ds Par6 are efficiently protected from M.persicae.Interfering with the genes involved in embryo development could be the effective RNAi targets for controlling aphids and potentially other insect pests. 展开更多
关键词 oilseed rape pest control APHID double-stranded RNA RNA interference
下载PDF
Contact Stress Reliability Analysis Model for Cylindrical Gear with Circular Arc Tooth Trace Based on an Improved Metamodel
6
作者 qi zhang Zhixin Chen +5 位作者 Yang Wu Guoqi Xiang Guang Wen Xuegang zhang Yongchun Xie Guangchun Yang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期593-619,共27页
Although there is currently no unified standard theoretical formula for calculating the contact stress of cylindrical gears with a circular arc tooth trace(referred to as CATT gear),a mathematical model for determinin... Although there is currently no unified standard theoretical formula for calculating the contact stress of cylindrical gears with a circular arc tooth trace(referred to as CATT gear),a mathematical model for determining the contact stress of CATT gear is essential for studying how parameters affect its contact stress and building the contact stress limit state equation for contact stress reliability analysis.In this study,a mathematical relationship between design parameters and contact stress is formulated using the KrigingMetamodel.To enhance the model’s accuracy,we propose a new hybrid algorithm that merges the genetic algorithm with the Quantum Particle Swarm optimization algorithm,leveraging the strengths of each.Additionally,the“parental inheritance+self-learning”optimization model is used to fine-tune the KrigingMetamodel’s parameters.Following this,amathematicalmodel for calculating the contact stress of Variable Hyperbolic Circular-Arc-Tooth-Trace(VH-CATT)gears using the optimized Kriging model was developed.We then examined how different gear parameters affect the VH-CATT gears’contact stress.Our simulation results show:(1)Improvements in R2,RMSE,and RMAE.R2 rose from0.9852 to 0.9974(a 1.22%increase),nearing 1,suggesting the optimized Kriging Metamodel’s global error is minimized.Meanwhile,RMSE dropped from3.9210 to 1.6492,a decline of 57.94%.The global error of the GA-IQPSO-Kriging algorithm was also reduced,with RMAE decreasing by 58.69%from 0.1823 to 0.0753,showing the algorithm’s enhanced precision.In a comparison of ten experimental groups selected randomly,the GA-IQPSO-Kriging and FEM-based contact analysis methods were used to measure contact stress.Results revealed a maximum error of 12.11667 MPA,which represents 2.85%of the real value.(2)Several factors,including the pressure angle,tooth width,modulus,and tooth line radius,are inversely related to contact stress.The descending order of their impact on the contact stress is:tooth line radius>modulus>pressure angle>tooth width.(3)Complex interactions are noted among various parameters.Specifically,when the tooth line radius interacts with parameters such as pressure angle,tooth width,and modulus,the resulting stress contour is nonlinear,showcasing amultifaceted contour plane.However,when tooth width,modulus,and pressure angle interact,the stress contour is nearly linear,and the contour plane is simpler,indicating a weaker coupling among these factors. 展开更多
关键词 CATT gear contact stress finite element method METAMODEL hybrid algorithm influencing factors
下载PDF
Experimental study on the influences of cutter geometry and material on scraper wear during shield TBM tunnelling in abrasive sandy ground
7
作者 Shaohui Tang Xiaoping zhang +3 位作者 Quansheng Liu qi zhang Xinfang Li Haojie Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期410-425,共16页
When shield TBM tunnelling in abrasive sandy ground,the rational design of cutter parameters is critical to reduce tool wear and improve tunnelling efficiency.However,the influence mechanism of cutter parameters on sc... When shield TBM tunnelling in abrasive sandy ground,the rational design of cutter parameters is critical to reduce tool wear and improve tunnelling efficiency.However,the influence mechanism of cutter parameters on scraper wear remains unclear due to the lack of a reliable test method.Geometry and material optimisation are often based on subjective experience,which is unfavourable for improving scraper geological adaptability.In the present study,the newly developed WHU-SAT soil abrasion test was used to evaluate the variation in scraper wear with cutter geometry,material and hardness.The influence mechanism of cutter parameters on scraper wear has been revealed according to the scratch characteristics of the scraper surface.Cutter geometry and material parameters have been optimised to reduce scraper wear.The results indicate that the variation in scraper wear with cutter geometry is related to the cutting resistance,frictional resistance and stress distribution.An appropriate increase in the front angle(or back angle)reduces the cutting resistance(or frictional resistance),while an excessive increase in the front angle(or back angle)reduces the edge angle and causes stress concentration.The optimal front angle,back angle and edge angle for quartz sand samples areα=25°,β=10°andγ=55°,respectively.The wear resistance of the modelled scrapers made of different metal materials is related to the chemical elements and microstructure.The wear resistances of the modelled scrapers made of 45#,06Cr19Ni10,42CrMo4 and 40CrNiMoA are 0.569,0.661,0.691 and 0.728 times those made of WC-Co,respectively.When the alloy hardness is less than 47 HRC(or greater than 58 HRC),scraper wear decreases slowly with increasing alloy hardness as the scratch depth of the particle asperity on the metal surface stabilizes at a high(or low)level.However,when the alloy hardness is between 47 HRC and 58 HRC,scraper wear decreases rapidly with increasing alloy hardness as the scratch depth transitions from high to low levels.The sensitive hardness interval and recommended hardness interval for quartz sand are[47,58]and[58,62],respectively.The present study provides a reference for optimising scraper parameters and improving cutterhead adaptability in abrasive sandy ground tunnelling. 展开更多
关键词 Shield TBM Scraper wear Cutter shape Metal material Alloy hardness
下载PDF
Prediction of high-embankment settlement combining joint denoising technique and enhanced GWO-v-SVR method
8
作者 qi zhang qian Su +2 位作者 Zongyu zhang Zhixing Deng De Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期317-332,共16页
Reliable long-term settlement prediction of a high embankment relates to mountain infrastructure safety.This study developed a novel hybrid model(NHM)that combines a joint denoising technique with an enhanced gray wol... Reliable long-term settlement prediction of a high embankment relates to mountain infrastructure safety.This study developed a novel hybrid model(NHM)that combines a joint denoising technique with an enhanced gray wolf optimizer(EGWO)-n-support vector regression(n-SVR)method.High-embankment field measurements were preprocessed using the joint denoising technique,which in-cludes complete ensemble empirical mode decomposition,singular value decomposition,and wavelet packet transform.Furthermore,high-embankment settlements were predicted using the EGWO-n-SVR method.In this method,the standard gray wolf optimizer(GWO)was improved to obtain the EGWO to better tune the n-SVR model hyperparameters.The proposed NHM was then tested in two case studies.Finally,the influences of the data division ratio and kernel function on the EGWO-n-SVR forecasting performance and prediction efficiency were investigated.The results indicate that the NHM suppresses noise and restores details in high-embankment field measurements.Simultaneously,the NHM out-performs other alternative prediction methods in prediction accuracy and robustness.This demonstrates that the proposed NHM is effective in predicting high-embankment settlements with noisy field mea-surements.Moreover,the appropriate data division ratio and kernel function for EGWO-n-SVR are 7:3 and radial basis function,respectively. 展开更多
关键词 High embankment Settlement prediction Joint denoising technique Enhanced gray wolf optimizer Support vector regression
下载PDF
Copper Metabolism and Cuproptosis:Molecular Mechanisms and Therapeutic Perspectives in Neurodegenerative Diseases
9
作者 Xiao-xia BAN Hao WAN +7 位作者 Xin-xing WAN Ya-ting TAN Xi-min HU Hong-xia BAN Xin-yu CHEN Kun HUANG qi zhang Kun XIONG 《Current Medical Science》 SCIE CAS 2024年第1期28-50,共23页
Copper is an essential trace element,and plays a vital role in numerous physiological processes within the human body.During normal metabolism,the human body maintains copper homeostasis.Copper deficiency or excess ca... Copper is an essential trace element,and plays a vital role in numerous physiological processes within the human body.During normal metabolism,the human body maintains copper homeostasis.Copper deficiency or excess can adversely affect cellular function.Therefore,copper homeostasis is stringently regulated.Recent studies suggest that copper can trigger a specific form of cell death,namely,cuproptosis,which is triggered by excessive levels of intracellular copper.Cuproptosis induces the aggregation of mitochondrial lipoylated proteins,and the loss of iron-sulfur cluster proteins.In neurodegenerative diseases,the pathogenesis and progression of neurological disorders are linked to copper homeostasis.This review summarizes the advances in copper homeostasis and cuproptosis in the nervous system and neurodegenerative diseases.This offers research perspectives that provide new insights into the targeted treatment of neurodegenerative diseases based on cuproptosis. 展开更多
关键词 cuproptosis copper metabolism copper homeostasis NEURODEGENERATION neurodegenerativedisease
下载PDF
Expert consensus on difficulty assessment of endodontic therapy
10
作者 Dingming Huang Xiaoyan Wang +33 位作者 Jingping Liang Junqi Ling Zhuan Bian qing Yu Benxiang Hou Xinmei Chen Jiyao Li Ling Ye Lei Cheng Xin Xu Tao Hu Hongkun Wu Bin Guo qin Su Zhi Chen Lihong qiu Wenxia Chen Xi Wei Zhengwei Huang Jinhua Yu Zhengmei Lin qi zhang Deqin Yang Jin Zhao Shuang Pan Jian Yang Jiayuan Wu Yihuai Pan Xiaoli Xie Shuli Deng Xiaojing Huang Lan zhang Lin Yue Xuedong Zhou 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第1期15-25,共11页
Endodontic diseases are a kind of chronic infectious oral disease. Common endodontic treatment concepts are based on the removal of inflamed or necrotic pulp tissue and the replacement by gutta-percha. However, it is ... Endodontic diseases are a kind of chronic infectious oral disease. Common endodontic treatment concepts are based on the removal of inflamed or necrotic pulp tissue and the replacement by gutta-percha. However, it is very essential for endodontic treatment to debride the root canal system and prevent the root canal system from bacterial reinfection after root canal therapy(RCT). Recent research, encompassing bacterial etiology and advanced imaging techniques, contributes to our understanding of the root canal system’s anatomy intricacies and the technique sensitivity of RCT. Success in RCT hinges on factors like patients, infection severity, root canal anatomy, and treatment techniques. Therefore, improving disease management is a key issue to combat endodontic diseases and cure periapical lesions. The clinical difficulty assessment system of RCT is established based on patient conditions, tooth conditions, root canal configuration, and root canal needing retreatment, and emphasizes pre-treatment risk assessment for optimal outcomes. The findings suggest that the presence of risk factors may correlate with the challenge of achieving the high standard required for RCT. These insights contribute not only to improve education but also aid practitioners in treatment planning and referral decision-making within the field of endodontics. 展开更多
关键词 ANATOMY DIFFICULTY TREATMENT
下载PDF
Unsupervised Multi-Expert Learning Model for Underwater Image Enhancement
11
作者 Hongmin Liu qi zhang +2 位作者 Yufan Hu Hui Zeng Bin Fan 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第3期708-722,共15页
Underwater image enhancement aims to restore a clean appearance and thus improves the quality of underwater degraded images.Current methods feed the whole image directly into the model for enhancement.However,they ign... Underwater image enhancement aims to restore a clean appearance and thus improves the quality of underwater degraded images.Current methods feed the whole image directly into the model for enhancement.However,they ignored that the R,G and B channels of underwater degraded images present varied degrees of degradation,due to the selective absorption for the light.To address this issue,we propose an unsupervised multi-expert learning model by considering the enhancement of each color channel.Specifically,an unsupervised architecture based on generative adversarial network is employed to alleviate the need for paired underwater images.Based on this,we design a generator,including a multi-expert encoder,a feature fusion module and a feature fusion-guided decoder,to generate the clear underwater image.Accordingly,a multi-expert discriminator is proposed to verify the authenticity of the R,G and B channels,respectively.In addition,content perceptual loss and edge loss are introduced into the loss function to further improve the content and details of the enhanced images.Extensive experiments on public datasets demonstrate that our method achieves more pleasing results in vision quality.Various metrics(PSNR,SSIM,UIQM and UCIQE) evaluated on our enhanced images have been improved obviously. 展开更多
关键词 Multi-expert learning underwater image enhancement unsupervised learning
下载PDF
Efficacy and safety of endoscopic submucosal dissection for early gastric cancer and precancerous lesions in elderly patients
12
作者 Wen-Si Xu Hui-Yu zhang +4 位作者 Shuang Jin qi zhang Hong-Dan Liu Ming-Tao Wang Bo zhang 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期511-517,共7页
BACKGROUND With advancements in the development of endoscopic technologies,the endo-scopic submucosal dissection(ESD)has been one of the gold-standard therapies for early gastric cancer.AIM To investigate the efficacy... BACKGROUND With advancements in the development of endoscopic technologies,the endo-scopic submucosal dissection(ESD)has been one of the gold-standard therapies for early gastric cancer.AIM To investigate the efficacy and safety ESD in the treatment of early gastric cancer and precancerous lesions in the elderly patients.METHODS Seventy-eight elderly patients with early gastric cancer and precancerous lesions admitted to the Third Affiliated Hospital of Qiqihar Medical University were se-lected and classified into two groups according to the different surgical therapies they received between January 2021 and June 2022.Among them,39 patients treated with ESD were included in an experimental group,and 39 patients treated with endoscopic mucosal resection(EMR)were included in a control group.We compared the basic intraoperative conditions,postoperative short-term recovery,long-term recovery effects and functional status of gastric mucosa between the two groups;the basic intraoperative conditions included lesion resection,intra-operative bleeding and operation time;the postoperative short-term recovery assessment indexes were length of hospital stay and incidence of surgical complic-ations;and the long-term recovery assessment indexes were the recurrence rate at 1 year postoperatively and the survival situation at 1 year and 3 years postoper-atively;and we compared the preoperative and predischarge serum pepsinogen I(PG I)and PG II levels and PG I/PG II ratio in the two groups before surgery and discharge.RESULTS The curative resection rate and the rate of en bloc resection were higher in the experimental group than in the control group.The intraoperative bleeding volume was higher in the experimental group than in the control group.The operation time was longer in the experimental group than that in the control group,and the rate for base residual focus was lower in the experimental group than that of the control group,and the differences were all statistically significant(all P<0.05).The length of hospital stay was longer in the experi-mental group than in the control group,and the incidence of surgical complications,1-year postoperative recu-rrence rate and 3-year postoperative survival rate were lower in the experimental group than in the control group,and the differences were statistically significant(all P<0.05).However,the difference in the 1-year postoperative survival rate was not statistically significant between the two groups(P>0.05).Before discharge,PG I and PG I/PG II ratio were elevated in both groups compared with the preoperative period,and the above indexes were higher in the experimental group than those in the control group,and the differences were statistically significant(both P<0.05).Moreover,before discharge,PG II level was lower in both groups compared with the preoperative period,and the level was lower in the experimental group than in the control group,and the differences were all statistically significant(all P<0.05).CONCLUSION Compared with EMR,ESD surgery is more thorough.It reduces the rate of base residual focus,recurrence rate,surgical complications,and promotes the recovery of gastric cells and glandular function.It is safe and suitable for clinical application. 展开更多
关键词 Endoscopic submucosal dissection Endoscopic mucosal resection Early gastric cancer Serum pepsinogen ELDERLY
下载PDF
Relationship between plasma risperidone concentrations and clinical features in chronic schizophrenic patients in China
13
作者 Jing-Wen Xu Xiao-Bo Guan +4 位作者 Xue-Ying Wang Yang Feng qi zhang Jun-Juan Zhu Jian-Hua Chen 《World Journal of Psychiatry》 SCIE 2024年第4期523-532,共10页
BACKGROUND Prior studies have noted great variability in the plasma levels of risperidone(RIS).Plasma concentrations of RIS and its active moiety are highly variable and depend on absorption,metabolism,and other predi... BACKGROUND Prior studies have noted great variability in the plasma levels of risperidone(RIS).Plasma concentrations of RIS and its active moiety are highly variable and depend on absorption,metabolism,and other predictors of metabolic dysregulation;however,these factors are poorly understood and the association between metabolic change and change in psychopathology is uncertain.AIM To ascertain the characteristics of chronic schizophrenic patients treated with RIS,and to assess their relationship with plasma RIS levels.METHODS This was a descriptive cross-sectional study of 50 patients with a diagnosis of schizophrenic psychosis treated with RIS in a psychiatric service.The plasma concentrations of RIS and its metabolite 9-hydroxyrisperidone were determined by high performance liquid chromatography.The patients’demographic and clinical characteristics,and psychopathologies were assessed,and the associations between clinical variables and plasma levels of RIS were explored.RESULTS Male patients received higher doses of RIS than female ones,but plasma concentrations of RIS and risperidone+9-hydroxyrisperidone(active moiety)were higher in female patients.Age and the mean scores of the general psychopathology subscale of the Positive and Negative Syndrome Scale(PANSS)were significantly positively correlated with plasma concentrations of risperidone+9-hydroxyrisperidone adjusted for weight and dose in all 50 subjects.In male subjects,we found a statistically significant positive correlation between the concentrations of risperidone+9-hydroxyrisperidone in plasma/(dose×kg)and age,mean PANSS negative subscale scores,mean PANSS general psychopathology subscale scores,and mean PANSS total scores.CONCLUSION Long-term use of RIS should be closely monitored in older patients and females to minimize the risk of high concentrations which could induce side effects. 展开更多
关键词 ANTIPSYCHOTICS RISPERIDONE 9-HYDROXYRISPERIDONE Plasma drug concentration monitoring Chronic schizophrenia
下载PDF
Will partial splenic embolization followed by splenectomy increase intraoperative bleeding?
14
作者 Long Huang qing-Lin Li +4 位作者 qing-Sheng Yu Hui Peng Zhou Zhen Yi Shen qi zhang 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期318-330,共13页
BACKGROUND Partial splenic embolization(PSE)has been suggested as an alternative to splenectomy in the treatment of hypersplenism.However,some patients may experience recurrence of hypersplenism after PSE and require ... BACKGROUND Partial splenic embolization(PSE)has been suggested as an alternative to splenectomy in the treatment of hypersplenism.However,some patients may experience recurrence of hypersplenism after PSE and require splenectomy.Currently,there is a lack of evidence-based medical support regarding whether preoperative PSE followed by splenectomy can reduce the incidence of complications.AIM To investigate the safety and therapeutic efficacy of preoperative PSE followed by splenectomy in patients with cirrhosis and hypersplenism.METHODS Between January 2010 and December 2021,321 consecutive patients with cirrhosis and hypersplenism underwent splenectomy at our department.Based on whether PSE was performed prior to splenectomy,the patients were divided into two groups:PSE group(n=40)and non-PSE group(n=281).Patient characteristics,postoperative complications,and follow-up data were compared between groups.Propensity score matching(PSM)was conducted,and univariable and multivariable analyses were used to establish a nomogram predictive model for intraoperative bleeding(IB).The receiver operating characteristic curve,Hosmer-Lemeshow goodness-of-fit test,and decision curve analysis(DCA)were employed to evaluate the differentiation,calibration,and clinical performance of the model.RESULTS After PSM,the non-PSE group showed significant reductions in hospital stay,intraoperative blood loss,and operation time(all P=0.00).Multivariate analysis revealed that spleen length,portal vein diameter,splenic vein diameter,and history of PSE were independent predictive factors for IB.A nomogram predictive model of IB was constructed,and DCA demonstrated the clinical utility of this model.Both groups exhibited similar results in terms of overall survival during the follow-up period.CONCLUSION Preoperative PSE followed by splenectomy may increase the incidence of IB and a nomogram-based prediction model can predict the occurrence of IB. 展开更多
关键词 Partial splenic embolization SPLENECTOMY Hypertension Portal Liver Cirrhosis Intraoperative bleeding
下载PDF
基于商学院国际认证理念的经管专业研究生创新素养的培育研究
15
作者 高鹏斌 张琦 +1 位作者 宋翌铎 刘业鑫 《教育研究前沿(中英文版)》 2024年第1期12-18,共7页
国际认证已经成为商学院提高竞争优势和促进持续发展的重要途径,其认证体系标准为商学院的发展提供了重要参考。文章介绍了AACSB、EQUIS和AMBA三大认证体系及其基本理念,以最新的2023版标准为依据,就其各自在创新方面的要求进行了分析... 国际认证已经成为商学院提高竞争优势和促进持续发展的重要途径,其认证体系标准为商学院的发展提供了重要参考。文章介绍了AACSB、EQUIS和AMBA三大认证体系及其基本理念,以最新的2023版标准为依据,就其各自在创新方面的要求进行了分析。在综合三大认证共同特征的基础上,从学院管理层面和教师引导层面,提出了经管类研究生创新素养的培育策略。 展开更多
关键词 AACSB EQUIS AMBA 商学院 研究生 创新素养
下载PDF
Analysis of the Current Situation of Drug Clinical Trial Institutions in Shaanxi Province
16
作者 Yurong zhang qi zhang +4 位作者 Li Wang Rui Xu Lili Zhao Enze Li Xin Wang 《Journal of Clinical and Nursing Research》 2024年第1期78-87,共10页
To understand the current situation of institutional registration in Shaanxi Province after the implementation ofregistration system management in drug clinical trial institutions.Relevant information was collected on... To understand the current situation of institutional registration in Shaanxi Province after the implementation ofregistration system management in drug clinical trial institutions.Relevant information was collected on the“Announcement on the Accreditation of Drug Clinical Trial Institutions”issued by the National Medical Products Administration from 2005 to August 2022,the record management information system of drug and medical device clinical trial institutions,and the drug clinical trial registration and information publicity platform.A retrospective analysis was carried out in terms of institutional development,regional distribution,registered majors,principal investigators,and the number of drug clinical trials.After the implementation of institution registration,the number of drug clinical trial institutions in Shaanxi Province increased by 47.4%,884 principal investigators were registered,the number of registered majors expanded from 58 qualified to 117,and the professional scope increased by 50.4%.The policy of institution registration is conducive to promoting the rational use of medical resources and the development of drug clinical trial institutions and improving the healthy development of the pharmaceutical industry in Shaanxi Province. 展开更多
关键词 Drug clinical trial Institution registration Registered majors Current situation analysis Professional group Shaanxi Province
下载PDF
Evaluation of Attending Medical Teams and Their Impact on the DRG Components of Cholecystectomy
17
作者 qi zhang Chuanyu Chen +3 位作者 Yan Wang Huachen Fan Wenping Sun Jing Deng 《Journal of Clinical and Nursing Research》 2024年第1期113-118,共6页
Objective:This study assessed the role of the attending medical team in the cost control of the cholecystectomy DRG components.Methods:The association between team structure,workflow,and treatment outcomes was analyze... Objective:This study assessed the role of the attending medical team in the cost control of the cholecystectomy DRG components.Methods:The association between team structure,workflow,and treatment outcomes was analyzed using a mixed-methods approach combining quantitative data and qualitative interviews from 628 patients.Results:Inter-professional teamwork significantly affected length of stay,treatment costs,and recurrence rates,with experienced teams performing better in terms of emergency response and collaborative efficiency.Patient satisfaction was generally high,indicating that good teamwork enhances treatment outcomes.Significance:The study highlights the importance of optimizing team configuration to improve the quality,efficiency,and cost control of healthcare. 展开更多
关键词 Attending medical team intervention Diagnosis-related group(DRG)system Healthcare quality and efficiency Interprofessional collaboration
下载PDF
大学生创新素养研究进展的文献计量学分析
18
作者 高鹏斌 宋翌铎 +1 位作者 张琦 刘业鑫 《教育研究前沿(中英文版)》 2024年第1期5-11,共7页
本文的目的是确定和探索大学生创新素养领域的研究发展状况。基于中国知网数据库中的83篇期刊论文,本文采用统计数据和可视化映射相结合的方法展开研究。在进行描述性统计的基础上,重点从关键词特征以及关键词共现关系网络入手分析研究... 本文的目的是确定和探索大学生创新素养领域的研究发展状况。基于中国知网数据库中的83篇期刊论文,本文采用统计数据和可视化映射相结合的方法展开研究。在进行描述性统计的基础上,重点从关键词特征以及关键词共现关系网络入手分析研究热点。结果表明,自2017年以来,发表论文的数量明显增加。期刊的跨学科整合是显而易见的,但较为分散尚未呈现重点刊物。学者合著网络的关联度不高,尚未形成具有重大影响力的群体。主要研究机构来自不同类型和水平的大学,但尚未形成重要流派。研究热点集中在培养体系、培养方法、培养路径、培养内容、培养特征、培养生态等方面。 展开更多
关键词 大学生 创新素养 文献计量学 研究进展
下载PDF
Research on the Application and Effectiveness of the DRG Model on Perioperative Medical Management of Cholecystectomy
19
作者 Chuanyu Chen Yan Wang +2 位作者 Zhen Wang Jing Deng qi zhang 《Journal of Clinical and Nursing Research》 2024年第2期228-233,共6页
Objective:This study aimed to explore the application and effectiveness of the DRG model in the perioperative management of cholecystectomy.By comparing the DRG model with traditional management methods,this study foc... Objective:This study aimed to explore the application and effectiveness of the DRG model in the perioperative management of cholecystectomy.By comparing the DRG model with traditional management methods,this study focused on evaluating the potential impact of the DRG model in improving surgical efficiency and reducing complication rates and medical costs.Methods:The random envelope method was used to divide patients scheduled for cholecystectomy from January 2021 to October 2023 into two groups:one group underwent surgery under the DRG model(experimental group),and the other group underwent the traditional management model(control group).Data including basic information,surgery-related data,length of stay,complication records,and medical expenses were collected.Data analysis was carried out using a t-test and chi-square(χ2)test.Results:Results showed that the DRG model shortened the average length of stay,decreased the incidence of complications,reduced medical expenses,and increased patient satisfaction.These results demonstrate the effectiveness of the DRG model in the perioperative management of cholecystectomy,especially in improving surgical efficiency,reducing medical costs,and improving patient satisfaction.Conclusion:The DRG model in the perioperative management of cholecystectomy can significantly improve medical service quality and efficiency and enhance patient satisfaction as compared to traditional treatment methods. 展开更多
关键词 DRG model CHOLECYSTECTOMY Medical management
下载PDF
The Antidepressant Mechanism of JiaWeiWenDan Decoction Regulating p38MAPK-ERK5 Signal Transduction Pathway
20
作者 Yue Gao qi zhang +1 位作者 Li Wu Jianye Dai 《Journal of Biosciences and Medicines》 2023年第4期199-207,共9页
Objective: To investigate the anti-depression mechanism of JiaWeiWenDan Decoction in regulating p38MAPK-ERK5 signal transduction pathway. Methods: Depression model rats were randomly divided into Blank Control Group, ... Objective: To investigate the anti-depression mechanism of JiaWeiWenDan Decoction in regulating p38MAPK-ERK5 signal transduction pathway. Methods: Depression model rats were randomly divided into Blank Control Group, Model Control Group, Chinese Medicine Treatment Group, and Western Medicine Treatment Group (hereinafter referred to as Blank Group, Model Group, Chinese Medicine Group, and Western Medicine Group), with 48 rats in each group. The mice were treated with p38MAPK-ERK5 on the 7th day, 14th day and 21st day, respectively, and the mice were treated for 28 days. The key targets and cytokines in p38MAPK-ERK5 signal transduction pathway were detected. Results: Compared with the Blank Group, the expression of p38MAPKmRNA in the hippocampus of the Model Group was increased. The Chinese Medicine Group and Western Medicine Group could reduce the expression of p38MAPK mRNA (P P P P Conclusion: The anti-inflammatory effect of JiaWeiWenDan Decoction may be related to the regulation of p38MAPK-ERK5 signaling pathway. With the advance of the treatment week, the best effect was obtained when the treatment was started on the 7th day of modeling. 展开更多
关键词 JiaWeiWenDan Decoction DEPRESSION p38MAPK-ERK5 Signal Transduction Pathway
下载PDF
上一页 1 2 31 下一页 到第
使用帮助 返回顶部