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User Purchase Intention Prediction Based on Improved Deep Forest
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作者 Yifan Zhang Qiancheng Yu Lisi Zhang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期661-677,共17页
Widely used deep neural networks currently face limitations in achieving optimal performance for purchase intention prediction due to constraints on data volume and hyperparameter selection.To address this issue,based... Widely used deep neural networks currently face limitations in achieving optimal performance for purchase intention prediction due to constraints on data volume and hyperparameter selection.To address this issue,based on the deep forest algorithm and further integrating evolutionary ensemble learning methods,this paper proposes a novel Deep Adaptive Evolutionary Ensemble(DAEE)model.This model introduces model diversity into the cascade layer,allowing it to adaptively adjust its structure to accommodate complex and evolving purchasing behavior patterns.Moreover,this paper optimizes the methods of obtaining feature vectors,enhancement vectors,and prediction results within the deep forest algorithm to enhance the model’s predictive accuracy.Results demonstrate that the improved deep forest model not only possesses higher robustness but also shows an increase of 5.02%in AUC value compared to the baseline model.Furthermore,its training runtime speed is 6 times faster than that of deep models,and compared to other improved models,its accuracy has been enhanced by 0.9%. 展开更多
关键词 Purchase prediction deep forest differential evolution algorithm evolutionary ensemble learning model selection
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Promoting sustainable consumption and circular economy:the intention of Vietnamese youth consumers to purchase products made from recycled plastics
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作者 Hong Thi Thu Nguyen 《Chinese Journal of Population,Resources and Environment》 2024年第2期194-203,共10页
Recycling is viewed as a key component in a circular economy and serves as an ideal solution for promoting sustainability.During the global plastic crisis,plastic recycling practices have been adopted worldwide,leadin... Recycling is viewed as a key component in a circular economy and serves as an ideal solution for promoting sustainability.During the global plastic crisis,plastic recycling practices have been adopted worldwide,leading to the production of various products made from recycled plastics(PRP).Nevertheless,a gap persists between consumption and demand for such products,which is primarily attributed to a lack of comprehension from the consumer perspective.Given the pivotal role consumers play in the adoption of these products,this study explores consumers’intentions to purchase PRP.This is particularly significant in Vietnam,which is an emerging economy aspiring to achieve the objectives of a circular economy and sustainable development.Utilizing an integrated cognitive-emotional framework comprising the Valence Theory and the Norm Activation Model,data from 564 Vietnamese students were gathered and analyzed using structural equation modeling.The results show that awareness of consequences is a major driver of consumer purchase intentions,followed by perceived ease of application and monetary incentives.The results also indicate that health concerns have the strongest effect on purchase intention and in the negative side,meaning that the health-related risk is the primary concern for consumers during the decision-making process.This research holds substantial value for academics and managers,as it aids in the theoretical exploration and the formulation of strategies to improve consumer acceptance of PRP. 展开更多
关键词 Recycled plastics Purchase intention Sustainable consumption Circular economy Valence theory Norm activation model
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Predicting Purchasing Behavior on E-Commerce Platforms: A Regression Model Approach for Understanding User Features that Lead to Purchasing
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作者 Abraham Jallah Balyemah Sonkarlay J. Y. Weamie +2 位作者 Jiang Bin Karmue Vasco Jarnda Felix Jwakdak Joshua 《International Journal of Communications, Network and System Sciences》 2024年第6期81-103,共23页
This research introduces a novel approach to improve and optimize the predictive capacity of consumer purchase behaviors on e-commerce platforms. This study presented an introduction to the fundamental concepts of the... This research introduces a novel approach to improve and optimize the predictive capacity of consumer purchase behaviors on e-commerce platforms. This study presented an introduction to the fundamental concepts of the logistic regression algorithm. In addition, it analyzed user data obtained from an e-commerce platform. The original data were preprocessed, and a consumer purchase prediction model was developed for the e-commerce platform using the logistic regression method. The comparison study used the classic random forest approach, further enhanced by including the K-fold cross-validation method. Evaluation of the accuracy of the model’s classification was conducted using performance indicators that included the accuracy rate, the precision rate, the recall rate, and the F1 score. A visual examination determined the significance of the findings. The findings suggest that employing the logistic regression algorithm to forecast customer purchase behaviors on e-commerce platforms can improve the efficacy of the approach and yield more accurate predictions. This study serves as a valuable resource for improving the precision of forecasting customers’ purchase behaviors on e-commerce platforms. It has significant practical implications for optimizing the operational efficiency of e-commerce platforms. 展开更多
关键词 E-Commerce Platform Purchasing Behavior Prediction Logistic Regression Algorithm
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Theoretical Analysis of Consumers’Purchase Motivation in the Context of Environmental Protection
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作者 Peiwei Zhang Ali Khatibi Jacquline Tham 《Journal of Contemporary Educational Research》 2024年第8期168-175,共8页
Through reviewing and summarizing the existing research on consumer motivation,and combining the characteristics of human behavior and the objective needs of environmental protection,this paper analyzes and defines co... Through reviewing and summarizing the existing research on consumer motivation,and combining the characteristics of human behavior and the objective needs of environmental protection,this paper analyzes and defines consumers’purchase motivation.In the context of environmental protection,purchase motivation is divided into demand motivation,value recognition motivation,recognition motivation,and interest motivation.Their definitions are given in this paper,which provides a conceptual basis for further research on the influence of purchase motivation on consumer behavior in the context of environmental protection. 展开更多
关键词 Environmental protection Purchase motivation Demand motivation Value recognition motivation Recognition motivation Interest motivation
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The Impact of E-Commerce Live Broadcasts on Consumers’Purchase Intention
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作者 Xingchao Bian Thanakon Ratchatakulpat Rattanavalee Maisak 《Proceedings of Business and Economic Studies》 2024年第4期263-268,共6页
E-commerce live broadcast has an important influence on consumers’purchase intention.The three dimensions of live broadcast content in the broadcast room are the number of comments,product quality,and live content as... E-commerce live broadcast has an important influence on consumers’purchase intention.The three dimensions of live broadcast content in the broadcast room are the number of comments,product quality,and live content as independent variables.A theoretical model is constructed with perceived value and risk as intermediaries and the consumers’purchase intention as the dependent variable,and corresponding hypotheses are put forward.We designed the scale,collected relevant data,and tested the model hypothesis using Statistical Package for Social Sciences(SPSS)and Analysis of Moment Structure(AMOS)software.The study found that the number of comments and product quality had a significant impact on perceived value,perceived risk,and consumers’purchase intention.From this conclusion,it is suggested that businesses should control the number of comments,strengthen the product quality of comments,and distinguish the repetition degree of the content of live broadcasts. 展开更多
关键词 Livestreaming e-commerce Perceived value Perceived risk Purchase intention
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Consumer Psychology in the Digital Age:How Online Environments Shape Purchasing Habits
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作者 Yanbin Ni 《Proceedings of Business and Economic Studies》 2024年第5期20-29,共10页
The advent of the digital age has profoundly changed consumers’mindsets and habits.The rapid development of e-commerce and the widespread use of mobile applications have created enormous demand for individual recomme... The advent of the digital age has profoundly changed consumers’mindsets and habits.The rapid development of e-commerce and the widespread use of mobile applications have created enormous demand for individual recommendation systems based on mass data.This system not only increases the convenience of purchases and conversions but also alters the purchasing behavior of consumers,leading them to make choices subconsciously.Potential risks associated with large-scale data sharing and usage have heightened consumer concerns regarding privacy,thereby weakening the foundational trust in platforms and deterring them from shopping.Additionally,the rapid growth of e-commerce in the digital age,coupled with changing market circumstances,has intensified psychological pressure on consumers,making their decision-making processes more complex and difficult.Furthermore,the program will explore issues related to improving customer experience,developing individual marketing strategies,and designing customer loyalty plans.It will also address questions of privacy in a digital environment,the dilemmas of excessive or disruptive consumption behavior,and the complexity and diversity of consumer behavior in the face of digital change.The objective of this study is to develop a fear study that will enable a better understanding of the impact of online shopping on consumer behavior and provide a strategic guide for retailers to meet the challenges and opportunities presented by the digital age. 展开更多
关键词 Digital age Consumer psychology Online shopping Purchasing habits Privacy protection Personalized recommendation
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Research on the Relationship Between Average Cigarette Price per Box and Government Procurement in City A Based on a Regression Model
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作者 Yao Nie Hongbo Wan Mingming Mao 《Proceedings of Business and Economic Studies》 2024年第5期68-72,共5页
This study aims to analyze and predict the relationship between the average price per box in the cigarette market of City A and government procurement,providing a scientific basis and support for decision-making.By re... This study aims to analyze and predict the relationship between the average price per box in the cigarette market of City A and government procurement,providing a scientific basis and support for decision-making.By reviewing relevant theories and literature,qualitative prediction methods,regression prediction models,and other related theories were explored.Through the analysis of annual cigarette sales data and government procurement data in City A,a comprehensive understanding of the development of the tobacco industry and the economic trends of tobacco companies in the county was obtained.By predicting and analyzing the average price per box of cigarette sales across different years,corresponding prediction results were derived and compared with actual sales data.The prediction results indicate that the correlation coefficient between the average price per box of cigarette sales and government procurement is 0.982,implying that government procurement accounts for 96.4%of the changes in the average price per box of cigarettes.These findings offer an in-depth exploration of the relationship between the average price per box of cigarettes in City A and government procurement,providing a scientific foundation for corporate decision-making and market operations. 展开更多
关键词 Cigarette marketing Regression model Predictive model Government purchasing
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A Study on the Factors Influencing Consumer Purchase Decision Under the Live-Streaming Sales Model
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作者 Zhaoxia Zhang Yating Mo Yijun Xia 《Journal of Electronic Research and Application》 2024年第3期185-190,共6页
In recent years,with the rapid development and popularization of Internet information technology,many new media platforms have risen rapidly,and major e-commerce companies have begun to explore the mode of livestreami... In recent years,with the rapid development and popularization of Internet information technology,many new media platforms have risen rapidly,and major e-commerce companies have begun to explore the mode of livestreaming.Especially during the COVID-19 pandemic,due to the lockdown,live-streaming has become an important means of economic development in many places.Owing to its remarkable characteristics of timeliness,entertainment,and interactivity,it has become the latest and trendiest sales mode of e-commerce channels,reflecting huge economic potential and commercial value.This article analyzes two models and their characteristics of live-streaming sales from a practical perspective.Based on this,it outlines consumer purchasing decisions and the factors that affect consumer purchasing decisions under the live-streaming sales model.Finally,it discusses targeted suggestions for using the live-streaming sales model to expand the consumer market,hoping to promote the healthy and steady development of the live-streaming sales industry. 展开更多
关键词 Live streaming sales model CONSUMERS Purchase decisions Influencing factors
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Enhancing Enterprise Efficiency through Cross-Domain Supply Chain Linkage Management
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作者 Hui Zhao 《Proceedings of Business and Economic Studies》 2024年第4期99-104,共6页
In recent years,with the complexity and variability of international finance,debt,and geopolitical risks,the growth rate of domestic economic operations has slowed down.More enterprise groups are facing the transforma... In recent years,with the complexity and variability of international finance,debt,and geopolitical risks,the growth rate of domestic economic operations has slowed down.More enterprise groups are facing the transformation and upgrading from domestic leadership to internationalization,achieving revenue growth of nearly 10 billion yuan per year against the trend.The severe and complex internal and external environment has brought many challenges to the supply chain for enterprises.This article focuses on the goal of an“enterprise supply chain system focusing on value creation,strengthening system linkage,and improving overall chain efficiency,”aiming to find solutions to problems such as strong demand variability,frequent emergency needs,coexistence of project shortages and inventory surplus,long material turnover cycles,and high organizational complexity.By searching for key activities in the entire business chain of demand,design,production,service,and finance,implementing source planning,process control,system linkage,analysis and summary,and team collaboration,we have achieved more scientific demand forecasting,more accurate planning,more effective procurement cost reduction,more stable production performance supply,more convenient inventory sharing services,and more efficient integration of business and financial policies. 展开更多
关键词 Supply chain management Full chain benefits Value creation Purchasing management
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Prediction of users online purchase behavior based on selective ensemble learning
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作者 谭惠 DUAN Yong 《High Technology Letters》 EI CAS 2023年第2期206-212,共7页
A probabilistic multi-dimensional selective ensemble learning method and its application in the prediction of users' online purchase behavior are studied in this work.Firstly, the classifier is integrated based on... A probabilistic multi-dimensional selective ensemble learning method and its application in the prediction of users' online purchase behavior are studied in this work.Firstly, the classifier is integrated based on the dimension of predicted probability, and the pruning algorithm based on greedy forward search is obtained by combining the two indicators of accuracy and complementarity.Then the pruning algorithm is integrated into the Stacking ensemble method to establish a user online shopping behavior prediction model based on the probabilistic multi-dimensional selective ensemble method.Finally, the research method is compared with the prediction results of individual learners in ensemble learning and the Stacking ensemble method without pruning.The experimental results show that the proposed method can reduce the scale of integration, improve the prediction accuracy of the model, and predict the user's online purchase behavior. 展开更多
关键词 users'online purchase behavior STACKING selective ensemble ensemble pruning feature engineering
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Optimization of Electricity Purchase and Sales Strategies of Electricity Retailers under the Condition of Limited Clean Energy Consumption
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作者 Peng Liao Hanlin Liu +1 位作者 Yingjie Wang Neng Liao 《Energy Engineering》 EI 2023年第3期701-714,共14页
In the process of my country’s energy transition,the clean energy of hydropower,wind power and photovoltaic power generation has ushered in great development,but due to the randomness and volatility of its output,it ... In the process of my country’s energy transition,the clean energy of hydropower,wind power and photovoltaic power generation has ushered in great development,but due to the randomness and volatility of its output,it has caused a certain waste of clean energy power generation resources.Regarding the purchase and sale of electricity by electricity retailers under the condition of limited clean energy consumption,this paper establishes a quantitative model of clean energy restricted electricity fromthe perspective of power system supply and demand balance.Then it analyzes the source-charge dual uncertain factors in the electricity retailer purchasing and selling scenarios in the mid-to long-term electricity market and the day-ahead market.Through the multi-scenario analysis method,the uncertain clean energy consumption and the user’s power demand are combined to form the electricity retailer’s electricity purchase and sales scene,and the typical scene is obtained by using the hierarchical clustering algorithm.This paper establishes a electricity retailer’s risk decisionmodel for purchasing and selling electricity in themid-and long-term market and reduce-abandonment market,and takes the maximum profit expectation of the electricity retailer frompurchasing and selling electricity as the objective function.At the same time,in themediumand longterm electricity market and the day-ahead market,the electricity retailer’s purchase cost,electricity sales income,deviation assessment cost and electricity purchase and sale risk are considered.The molecular results show that electricity retailers can obtain considerable profits in the reduce-abandonment market by optimizing their own electricity purchase and sales strategies,on the premise of balancing profits and risks. 展开更多
关键词 Electricity retailer electricity purchase and sale strategy clean energy consumption
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Nonfarm employment, agricultural machinery service purchase and agricultural production efficiency:An empirical study based on China's major wheat-producing areas
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作者 JI Lin 《Ecological Economy》 2023年第3期257-270,共14页
Based on the cross-sectional data of the survey conducted in China's main wheat producing areas at the end of 2019,this paper uses the translog production function model to estimate agricultural technical efficien... Based on the cross-sectional data of the survey conducted in China's main wheat producing areas at the end of 2019,this paper uses the translog production function model to estimate agricultural technical efficiency,and studies the relationship between nonfarm employment,agricultural machinery service purchase and agricultural production efficiency.The results show that the household non-agricultural employment ratio and non-agricultural income have a significant positive impact on the purchase of agricultural machinery services.In addition to the effect of scale efficiency,non-agricultural employment does not have a significant impact on agricultural technical efficiency,and labor transfer does not have a significant negative impact on agricultural production. 展开更多
关键词 nonfarm employment agricultural machinery service purchase agricultural technical efficiency
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YKK achieves 100% renewable energy purchasing at 31 sites worldwide
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《China Textile》 2023年第2期40-41,共2页
YKK Corporation announces that the number of YKK locations that have switched 100%of their electricity consumption to renewable energy in fiscal year 2022 has increased by 20 locations from FY2021 to FY2022,reaching 3... YKK Corporation announces that the number of YKK locations that have switched 100%of their electricity consumption to renewable energy in fiscal year 2022 has increased by 20 locations from FY2021 to FY2022,reaching 31 locations globally. 展开更多
关键词 PURCHASING globally ENERGY
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65% Aussie clothes buyers actively prioritise ethical factors
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《China Textile》 2023年第2期58-58,共1页
Over 65 per cent of respondents actively consider ethical factors when purchasing clothes,while nearly a third explicitly consider the human rights of garment workers,as per a survey.The safety of garment work­er... Over 65 per cent of respondents actively consider ethical factors when purchasing clothes,while nearly a third explicitly consider the human rights of garment workers,as per a survey.The safety of garment work­ers are top priorities for 88 per cent of Australian clothing buyers.Younger generations are more likely to make ethical purchasing decisions. 展开更多
关键词 PURCHASING LIKELY ETHICAL
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赋能供应链成本管理能力 助力车企降本增效方法研究
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作者 朱虹 陆亦伟 《世界汽车》 2023年第2期82-83,共2页
站在供应链的高度,以促进供应商降本为抓手,发挥供应链降本优势。本文以供应链降本应用于车企实现成本控制各种方法出发,对汽车成本控制的有效策略进行分析,以期为相关工作提供理论的参考与借鉴。
关键词 供应链降本 VA/VE ESI Target Costing Leveraging Purchases
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The Role of Rivers in the United States 19th Century Territorial Expansion from the Mississippi River to the Pacific Ocean
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作者 Kenneth Ray Olson 《Open Journal of Soil Science》 2023年第12期517-533,共17页
This study explores the key role of rivers in the westward expansion of the United States during the 19th century. In the early 1800s, President Jefferson envisioned a United States that extended from the Atlantic to ... This study explores the key role of rivers in the westward expansion of the United States during the 19th century. In the early 1800s, President Jefferson envisioned a United States that extended from the Atlantic to the Pacific Ocean. At the time, the entire United States territory was located between the Atlantic Ocean and the Mississippi River. Much of the land west of the Mississippi River was claimed by Spain, France, or Canada. In 1803, President Jefferson was able to purchase the Missouri River watershed from France via the Louisiana Purchase. This allowed the United States to extend its land claim west from the confluence of the Missouri and Mississippi Rivers to the head waters of the Missouri River at the continental divide in the Rocky Mountains. President Jefferson commissioned William Clark and Meriwether Lewis, in 1803, to explore, discover and describe the Missouri River watershed and find a water route to the Pacific Ocean. The Lewis and Clark Corps of Discovery trip found no such waterway link but did continue to explore the Pacific Northwest lands north and west of the continental divide. The only way that the Pacific Northwest could be claimed as part of the United States was for Americans to settle there before the Canadians did. Starting in the 1820s, many Americans traveled via the Oregon Trail to the Willamette Valley (Land of Flowing Milk and Honey) in Oregon. The primary objectives of this study are to document how the United States: 1) extended its land claims west from the Mississippi River to the North American continental drainage divide;2) established an American claim to the Pacific North West territory;and 3) fulfilled President Jefferson’s vision of a United States extending from the Atlantic to the Pacific Ocean. 展开更多
关键词 Louisiana Purchase President Thomas Jefferson Oregon Trail Corps of Discovery Sacagawea Missouri River
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Quality Management Research on the Purchasing of Food Processing Enterprises
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作者 魏国辰 王海鹏 《Agricultural Science & Technology》 CAS 2013年第12期1870-1876,共7页
In order to improve the purchased goods quality management level of food processing enterprises, the causes of quality management problems were ana- lyzed, which were classified into four categories, namely, natural t... In order to improve the purchased goods quality management level of food processing enterprises, the causes of quality management problems were ana- lyzed, which were classified into four categories, namely, natural toxins in raw ma- terials, quality problems in planting and breeding, quality problems in transportation, quality problems in delivery acceptance. Then, based on the causes, eight measures to improve goods purchasing management were put forward, and graphs were used to illustrate the corresponding countermeasure to each cause. This study is of theo- retical significance for the food processing enterprises to improve the quality man- agement of purchased goods through formulating improvement measures based on their operating states. 展开更多
关键词 Food processing enterprises Raw materials purchased goods quality Quality improvement measures
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A model of targeted advertising with customer recognition 被引量:4
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作者 张建强 仲伟俊 梅姝娥 《Journal of Southeast University(English Edition)》 EI CAS 2012年第4期490-495,共6页
A two-period duopoly model is developed to examine the competitive effects of targeted advertising with customer recognition (TACR). In the model, two competing firms sell goods to end consumers in the first period,... A two-period duopoly model is developed to examine the competitive effects of targeted advertising with customer recognition (TACR). In the model, two competing firms sell goods to end consumers in the first period, during which customer recognition is obtained. In the second period, advertising can be targeted toward different consumer types. Advertising is assumed to be persuasive in the way that consumer valuation is increased. Equilibrium decisions and profits in each period are derived, showing that the firm who loses the current competition will win in the future. As a result, forward-looking firms price less aggressively so that their long-term profits can be enhanced with the help of TACR. Particularly, TACR improves profits through three important effects: valuation increasing, customer poaching, and anti-competition. Finally, this paper investigates the welfare issues, showing that firms enhance profits at the expense of consumer surplus. It is, therefore, suggested that public sectors take a step to protect consumers with the rapid development of targeting technology. 展开更多
关键词 targeted advertising customer recognition price discrimination purchase history
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药品带量采购的核心要素分析 被引量:23
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作者 常峰 《中国卫生资源》 北大核心 2021年第1期15-19,共5页
明确药品带量采购的核心要素及相关理论,深入分析和比较我国实施的3批药品集中采购的相关政策,厘清我国药品带量采购模式的演进历程和发展趋势,以期为优化我国医药采购制度、增进人民群众健康福祉提供参考。
关键词 药品drug 集中采购centralized purchasing 带量采购purchasing with quantity 核心要素core element
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Influence of mild hypothermia on vascular endothelial growth factor and infarct volume in brain tissues after cerebral ischemia in rats 被引量:2
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作者 Fei Ye1, Gangming Xi1, Biyong Qin1, Shifeng Wang1, Chengyan Li2 1Department of Neurology, People’s Hospital of Yunyang Medical College, Shiyan 442000, Hubei Province, China 2Department of Neurology, Renmin Hospital of Wuhan University, Wuhan 430060, Hubei Province, China 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第9期847-849,共3页
BACKGROUND: It has been demonstrated that mild hypothermia has obvious protective effect on both whole and local cerebral ischemia. However, the definite mechanism is still unclear for the brain protection of mild hyp... BACKGROUND: It has been demonstrated that mild hypothermia has obvious protective effect on both whole and local cerebral ischemia. However, the definite mechanism is still unclear for the brain protection of mild hypothermia on cerebral edema, inhibiting inflammatory reaction, stabilizing blood brain barrier, etc. OBJECTIVE: To investigate the effect of mild hypothermia on the expression of vascular endothelial growth factor and the infarct volume after cerebral ischemia in rats, and analyze the brain protective mechanism of mild hypothermia. DESIGN: A randomized grouping and controlled animal trial. SETTING: Department of Neurology, People’s Hospital of Yunyang Medical College. MATERIALS: Twenty adult male SD rats of clean degree, weighing (250±30) g, were provided by the animal experimental center, School of Medicine, Wuhan University. The kits for SP immunohistochemistry were purchased from Beijing Zhongshan Golden Bridge Biotechnology Co., Ltd. METHODS: The experiments were carried out in the laboratory of Department of Neurology, Renmen Hospital of Wuhan University from May to July 2005. ① The 20 rats were divided randomly into normal temperature group (n =10) and mild hypothermia group (n =10). Models of permanent middle cerebral artery occlusion were established with modified nylon suture embolization. The rats were assessed with the Longa standards: 0 point for without nerve dysfunction; 1 for mild neurological deficit (fore claws could no extend completely); 2 for moderate neurological deficit (circling towards the affected side); 3 for severe neurological deficit (tilting towards the affected side); 4 for coma and unconscious; 1-3 points represented that models were successfully established. The rats of the normal temperature group were fed at room temperature, and those in the mild hypothermia group were induced by hypothermia from 2 hours postoperatively, and the rectal temperature was kept at 34-35 ℃ for 72 hours. ② Measurement of infarct volume: All the rats were anesthetized by intraperitoneal injection overdose sodium pentobarbital 7 days postoperatively, and then the heads were cut down to harvest brain. The brain tissues were placed into -20 ℃ refrigerator for 20 minutes, coronal sections of 2 mm were prepared. The infarct sites were not stained, whereas normal brain tissues were stained as red. The infarct volumes were calculated by using MPLAS-500 multimedia color pathological image&word analytical system. ③ Counting positive cells of vascular endothelial growth factor protein: The brains were harvested by cutting heads, then coronal sections of 2 mm were prepared. Routine dehydration, hyalinization, wax immersion and embedding were performed, then the detected with SP immunohistochemistry, the kits were purchased from Beijing Zhongshan Golden Bridge Biotechnology Co., Ltd. The cells whose cytoplasm was yellow-brown were positive ones, a single sample as a unit, peri-ischemic site and ischemic core were selected, and the corresponding sites in controlateral hemisphere were taken as controls. Five visual fields were selected from each site to be observed under microscope, the cells were counted, and the average number of positive cells was calculated in each group. The numbers of positive cells were determined with the image analytical apparatus. MAIN OUTCOME MEASURES: Number of the positive cells of vascular endothelial growth factor protein; Infarct volume of rat brain tissue. RESULTS: All the 20 rats were involved in the analysis of results. ① Number of positive cells of vascular endothelial growth factor protein in brain tissue: It was obviously lower in the mild hypothermia group than in the normal temperature group [(24.02±5.05), (36.07±2.69) cells/high power visual field, P < 0.01]. ② Comparison of infarct volume of brain tissue: After MCAO, it was obviously smaller in the mild hypothermia group than in the normal temperature group [(153.25±23.14), (253.45±36.21) mm3, P < 0.01]. CONCLUSION: Mild hypothermia can inhibit the expression of vascular endothelial growth factor and decrease the volume of cerebral infarction. The inhibition of mild hypothermia on the expression of vascular endothelial growth factor may be one of the brain protective mechanisms. 展开更多
关键词 INFARCT NEUROLOGICAL purchased HEMISPHERE protective minutes Biotechnology stained OCCLUSION WUHAN
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