期刊文献+
共找到446篇文章
< 1 2 23 >
每页显示 20 50 100
How R&D investment promotes green technology innovation in the context of digitalization?-An empirical analysis based on provincial panel data
1
作者 LIU Jie LI Zhi-hui WEI Fang-xin 《Ecological Economy》 2024年第1期39-52,共14页
Green technology innovation is an important driving force and source to promote my country’s high-quality development,and it is the core path to achieve sustainable development.This paper uses my country’s provincia... Green technology innovation is an important driving force and source to promote my country’s high-quality development,and it is the core path to achieve sustainable development.This paper uses my country’s provincial panel data from 2016 to 2019 to study the impact mechanism of R&D investment on green technology innovation,and introduces the level of digitization,using the panel threshold model to discuss its role in the impact mechanism of R&D investment on green technology innovation.The study found that when the level of digitalization in a region is low,increasing R&D investment does not necessarily improve the ability of green technology innovation;when the level of digitalization is relatively high,R&D investment has a positive role in promoting green technology innovation.Therefore,it is necessary to improve policies to encourage enterprises to increase investment in research and development;at the same time,it is necessary to promote the coordinated development of digital foundation,digital investment,digital literacy,digital economy and digital application,and promote the deep integration of digitalization and green technology innovation. 展开更多
关键词 green technology innovation r&d investment digital level panel model
下载PDF
Research on the Threshold Effect of China’s Pharmaceutical Export Trade on Internal and External R&D Investment
2
作者 Qiao Jiahui Song Yu +1 位作者 Gong Jingran Chen Yuwen 《Asian Journal of Social Pharmacy》 2024年第2期135-146,共12页
Objective To study the threshold effect of export trade on internal and external R&D investment in China’s pharmaceutical industry,and to provide reference for some pharmaceutical enterprises to improve the inves... Objective To study the threshold effect of export trade on internal and external R&D investment in China’s pharmaceutical industry,and to provide reference for some pharmaceutical enterprises to improve the investment.Methods The panel data of pharmaceutical industry in 25 provinces and cities in China from 2009 to 2019 were selected to conduct empirical analysis by establishing a threshold regression model,and a better export trade interval was obtained.Results and Conclusion There is a threshold value for the effect of new product export on both internal and external R&D expenditures,and the threshold values are 845.2788 million yuan and 318.4198 million yuan,respectively.There is a single threshold effect of export trade on both internal and external R&D investment in China’s pharmaceutical industry,and the effect of export trade on internal and external R&D investment changes from negative to positive as the export trade develops from low to high. 展开更多
关键词 pharmaceutical industry threshold effect export trade r&d investment
下载PDF
Research on Correlation between Employees' Heterogeneity Characteristics and R&D Investment
3
作者 Hu Yuanmu Liu Pei 《Review of Global Academics》 2015年第1期488-492,共5页
Using all Chinese firms listed on the stock exchanges during 2007-2012, we examined the influence of employees' heterogeneity characteristics on R&D investment. The empirical result showed that employees' educatio... Using all Chinese firms listed on the stock exchanges during 2007-2012, we examined the influence of employees' heterogeneity characteristics on R&D investment. The empirical result showed that employees' educational level and R&D investment is a significant positive correlation. We also proved the number of technical employee has a positive effect on R&D. 展开更多
关键词 Employees' heterogeneity Characteristics rd investment level of Education: Technical Employees
下载PDF
Discreet investors exert greater influence on cooperation in the public goods game
4
作者 康洪炜 金展瑶 +4 位作者 李明远 旺咩 孙兴平 沈勇 陈清毅 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期170-178,共9页
This paper studies the evolutionary process of cooperative behavior in a public goods game model with heterogeneous investment strategies in square lattices.In the proposed model,players are divided into defectors,coo... This paper studies the evolutionary process of cooperative behavior in a public goods game model with heterogeneous investment strategies in square lattices.In the proposed model,players are divided into defectors,cooperators and discreet investors.Among these,defectors do not participate in investing,discreet investors make heterogeneous investments based on the investment behavior and cooperation value of their neighbors,and cooperators invest equally in each neighbor.In real life,heterogeneous investment is often accompanied by time or economic costs.The discreet investors in this paper pay a certain price to obtain their neighbors'investment behavior and cooperation value,which quantifies the time and economic costs of the heterogeneous investment process.The results of Monte Carlo simulation experiments in this study show that discreet investors can effectively resist the invasion of the defectors,form a stable cooperative group and expand the cooperative advantage in evolution.However,when discreet investors pay too high a price,they lose their strategic advantage.The results in this paper help us understand the role of heterogeneous investment in promoting and maintaining human social cooperation. 展开更多
关键词 public goods game heterogeneous investment discreet investors COOPErATION
下载PDF
Effects of investment on energy intensity:evidence from China 被引量:2
5
作者 Junbing Huang Shiwei Yu 《Chinese Journal of Population,Resources and Environment》 2016年第3期197-207,共11页
This article explores the effects of investment upon energy intensity by applying a unique panel data of China's 27 provinces between 2004 and 2013.In addition,it also particularly stuthes other factors,such as en... This article explores the effects of investment upon energy intensity by applying a unique panel data of China's 27 provinces between 2004 and 2013.In addition,it also particularly stuthes other factors,such as energy price,economic structure,and urbanization.The results,based on four econometric regression model results,suggest that in general,the indigenous investment on research and development is a more powerful tool to decrease China's energy intensity regardless of region disparity.The foreign direct investment(FDI) has a prominent but not persistent effect on energy intensity.However,the outward direct investment has not shown its significant impact on energy intensity.At the level of an aggregate economy and China's eastern region,the results demonstrate that FDI improves energy efficiency significantly.For the central and western provinces,FDI does not support the similar conclusion.Based on these analyses,we present the corresponding regional policies for policymakers. 展开更多
关键词 Energy intensity research and development(r&d) foreign direct investment outward direct investment
下载PDF
Spatiotemporal Characteristics of Typical Ecosystem Services and Their Spatial Responses to Driving Factors in Ecologically Fragile Areas in Upper Yellow River,China
6
作者 LIANG Gui FANG Fengman +1 位作者 LIN Yuesheng ZHANG Zhiming 《Chinese Geographical Science》 SCIE CSCD 2024年第4期674-688,共15页
The identification of dominant driving factors for different ecosystem services(ESs)is crucial for ecological conservation and sustainable development.However,the spatial heterogeneity of the dominant driving factors ... The identification of dominant driving factors for different ecosystem services(ESs)is crucial for ecological conservation and sustainable development.However,the spatial heterogeneity of the dominant driving factors affecting various ESs has not been adequately elucidated,particularly in ecologically fragile regions.This study employed the integrated valuation of ESs and trade-offs(InVEST)model to evaluate four ESs,namely,water yield(WY),soil conservation(SC),habitat quality(HQ),and carbon storage(CS),and then to identify the dominant driving factors of spatiotemporal differentiation of ES and further to characterize the spatial heterogeneity characteristics of the dominant driving factors in the eco-fragile areas of the upper Yellow River,China from 2000 to 2020.The results demonstrated that WY exhibited northeast-high and northwest-low patterns in the upper Yellow River region,while high values of SC and CS were distributed in central forested areas and a high value of HQ was distributed in vast grassland areas.The CS,WY,and SC exhibited decreasing trends over time.The most critical factors affecting WY,SC,HQ,and CS were the actual evapotranspiration,precipitation,slope,and normalized difference vegetation index,respectively.In addition,the effects of different factors on various ESs exhibited spatial heterogeneity.These results could provide spatial decision support for eco-protection and rehabilitation in ecologically fragile areas. 展开更多
关键词 integrated valuation of ecosystem services and trade-offs(InVEST)model geographically weighted regression(GWr) natural factor spatial heterogeneity Lanxi urban agglomeration upper Yellow river China
下载PDF
Research on the Relationship between Export Orientation and R&D Investment of China’s Pharmaceutical Industry in Different Regions 被引量:1
7
作者 Qiao Jiahui Wang Su Chen Yuwen 《Asian Journal of Social Pharmacy》 2021年第1期48-59,共12页
Objective To study the relationship between export orientation and research and development(R&D)investment so as to provide suggestions and references for improving the R&D investment level and innovation capa... Objective To study the relationship between export orientation and research and development(R&D)investment so as to provide suggestions and references for improving the R&D investment level and innovation capabilities of pharmaceutical industry due to the progress of globalization and the continuous development of export trade of China’s pharmaceutical industry.Methods The relevant data of China’s pharmaceutical industry from 2001 to 2016 was selected to establish an error correction model based on the co-integration theory,and then the Granger causality test was conducted to determine the relationship between the export orientation and R&D investment of China’s pharmaceutical industry in different regions.Results and Conclusion It is found that the export orientation of the pharmaceutical industry in different regions has a significant negative impact on the investment of R&D.Among them,the middle region has the greatest impact,followed by the eastern and western regions.The export orientation of the pharmaceutical industry in the middle region has a lag effect on R&D investment,and the lag phase is two years. 展开更多
关键词 pharmaceutical industry export orientation r&d investment co-integration analysis
下载PDF
Demonstration Analysis of Relationship Between R&D Investment and GDP
8
作者 韩伯棠 刘百善 陈铿 《Journal of Beijing Institute of Technology》 EI CAS 2005年第1期96-99,共4页
To reveal the quantitative relationship between research and development (R&D) investment and gross domestic product (GDP) in China, we have demonstrated and analyzed the relationship between R&D investment an... To reveal the quantitative relationship between research and development (R&D) investment and gross domestic product (GDP) in China, we have demonstrated and analyzed the relationship between R&D investment and science and technology (S&T) progress, and based on a mount of S&T statistical data, have proceeded demonstration research of the relationship between R&D investment and GDP in China with Solow and vector auto regression (VAR) models. Cubic curve fitting and cross-correlation analysis of them with SPSS have shown that there is a strong synchronic relationship between R&D investment and GDP. 展开更多
关键词 research and development (r&d) investment gross domestic product (GdP) Solow model vector auto regression (VAr) model
下载PDF
Research on the Impact of Venture Risk Tolerance on R&D investments:Based on Entrepreneur Ability
9
作者 Weng Yaqin Han Wucheng 《Contemporary Social Sciences》 2022年第2期59-76,共18页
How do start-ups enhance risk tolerance and core competition through product,technology,and service development?What is the relationship between the core competitiveness of start-ups and R&D investments?Based on t... How do start-ups enhance risk tolerance and core competition through product,technology,and service development?What is the relationship between the core competitiveness of start-ups and R&D investments?Based on the perspective of entrepreneurial ability,222 questionnaires were used to study the factors affecting the risk tolerance of start-ups and analyze the effect of risk tolerance on R&D investments.The research shows that the interactions of entrepreneur ability and start-up funds have a positive effect on the risk tolerance of start-ups,and the risk tolerance can positively promote R&D investment willingness and intensity for new products,technologies,and services.Also,R&D investment willingness plays a partial intermediary role between the risk tolerance of start-ups and the intensity of R&D investments. 展开更多
关键词 STArT-UPS entrepreneurial ability start-up funds risk tolerance r&d investments
下载PDF
Relationship between R&D investment and business performance from the perspective of environmental regulation: Takeing the heavy-polluting industries from 2011 to 2016 as an example
10
作者 ZHAO Yu YUE Hong HUANG Ya-jing 《Ecological Economy》 2017年第3期213-226,共14页
In recent years, China has promulgated many laws and regulations of environmental protection, gradually forming an environmental regulation system, and most enterprises are under the dual pressure of environmental pro... In recent years, China has promulgated many laws and regulations of environmental protection, gradually forming an environmental regulation system, and most enterprises are under the dual pressure of environmental protection and business performance. It would be a significant way that enterprises undertake R&D activities for a change. This paper is based on the Shanghai and Shenzhen A-share listed heavy pollution enterprises in 2011-2016, which is based on the review and summary of research results of former researchers, combining with current environmental regulation situation of our country, raising the relevant hypothesis between environmental regulations, R&D investment and business performance against heavy pollution industry. Adopting the method of empirical research, it also built the linear regression model which employs the relevant financial data of heavy-polluting enterprises in China as the statistical research sample. The relationship for heavy-polluting enterprises affected by environmental regulations between environmental protection R&D investment and enterprise business performance was tested. The results show that there is a positive influence on the environmental R&D investment and business performance, and a lag effect upon the R&D investment of enterprises to business performance. Finally, the research results were used to evaluates problems existing in the R&D investment on pollution industry in China as well as business performance and we put forward some suggestions on improving environmental regulation standards and technology innovation consciousness as well as optimizing the structure of R&D investment. 展开更多
关键词 environmental regulation r&d investment business performance empirical research
下载PDF
Research on the Relationship between Salary Incentives for R&D Personnel and R&D Investment in China’s Pharmaceutical Industry
11
作者 Wang Yuzhuo Wang Su Chen Yuwen 《Asian Journal of Social Pharmacy》 2021年第4期295-304,共10页
Objective To explore the relationship between salary incentives for R&D personnel and R&D investment in China’s pharmaceutical industry through an empirical analysis so as to propose suggestions for increasin... Objective To explore the relationship between salary incentives for R&D personnel and R&D investment in China’s pharmaceutical industry through an empirical analysis so as to propose suggestions for increasing more R&D investment from the perspective of stimulating R&D personnel.Methods Based on the relevant data of the China’s pharmaceutical industry in the“China High-tech Industry Statistical Yearbook”and other data from the National Bureau of Statistics from 1995 to 2018,co-integration tests was used to construct error correction models and Granger causality tests to explore the relationship between R&D personnel salary incentives and R&D investment.Results and Conclusion There is a long-term balanced relationship between the salary level of R&D personnel in China’s pharmaceutical industry and the investment of R&D.For the per capita salary of R&D personnel increases by 1 unit,the internal expenditure of R&D investment will increase by 2.2451 units.In the short term,the per capita salary of R&D personnel has a slight negative impact on the internal expenditure of R&D investment.In addition,the salary incentives for R&D personnel have the most significant role in promoting R&D investment after five years of implementation. 展开更多
关键词 pharmaceutical industry r&d investment salary incentives for r&d personnel cointegration test
下载PDF
Economic Policy Uncertainty,Heterogeneity of Executives and Enterprise Innovation
12
作者 Xun Han Yuyan Jiang Xianjing Huang 《Journal of Business Administration Research》 2021年第3期36-50,共15页
This study analyzes how economic policy uncertainty affects corporate innovation,and the moderating effects of executive heterogeneity.A threephase dynamic investment and financing model is first built to analyze the ... This study analyzes how economic policy uncertainty affects corporate innovation,and the moderating effects of executive heterogeneity.A threephase dynamic investment and financing model is first built to analyze the mechanism.Empirical analysis confirms that the increase in the degree of economic policy uncertainty promotes enterprise innovation.Further results show that this promotion effect is more significant in enterprises with male executives,low educational level,no financial experience and political background.Moreover,the positive impact is only found in enterprises with moderate executive ability,and the overconfidence of senior executives plays a positive regulating role in it. 展开更多
关键词 Economic policy uncertainty Executive heterogeneity r&d Political association
下载PDF
Research on the Relationship between the Profitability and R&D Investment of Enterprises of Different Scales in China’s Pharmaceutical Industry
13
作者 Kudireti·shataer Chen Yuwen 《Asian Journal of Social Pharmacy》 2021年第4期305-319,共15页
Objective To analyze the relationship between the profitability of pharmaceutical enterprises of different scales and their R&D investment.Methods The data of China’s pharmaceutical manufacturing industry from 19... Objective To analyze the relationship between the profitability of pharmaceutical enterprises of different scales and their R&D investment.Methods The data of China’s pharmaceutical manufacturing industry from 1995 to 2016 were selected to establish a vector auto-regression mode,and then an impulse response function and variance decomposition were used to analyze the data.Results and Conclusion For large-scale pharmaceutical enterprises,1%increase in R&D input will lead to 0.792%increase of their main business profit.For medium-sized enterprises,if their main business profit increases by 1%,their R&D input will increase by 0.965%.Therefore,if their R&D input increases by 1%,their main business profit will increase by 1.036%.The improvement of the profitability of large-scale pharmaceutical enterprises cannot promote the increase of R&D capital investment.But the increase of profitability from medium-sized enterprises can promote the increase of R&D capital investment.As a result,the increase of R&D capital investment of large and medium-sized enterprises can improve corporate profitability. 展开更多
关键词 pharmaceutical enterprises PrOFITABILITY r&d investment vector auto-regression(VAr)mode
下载PDF
企业行为理论视角下的家族企业异质性、R&D投入与企业价值 被引量:14
14
作者 严若森 叶云龙 江诗松 《管理学报》 CSSCI 北大核心 2016年第10期1499-1508,共10页
基于企业行为理论视角界定家族企业的异质性,并以2007~2012年中国家族上市公司为研究对象,实证检验家族企业R&D投入的影响因素与异质化价值效应的作用机理。研究表明:1当家族企业的实际绩效低于期望绩效时,期望绩效差与R&D投入强度... 基于企业行为理论视角界定家族企业的异质性,并以2007~2012年中国家族上市公司为研究对象,实证检验家族企业R&D投入的影响因素与异质化价值效应的作用机理。研究表明:1当家族企业的实际绩效低于期望绩效时,期望绩效差与R&D投入强度正相关;反之,实际绩效高于期望绩效时,期望绩效差与R&D投入强度负相关。2当实际绩效低于期望绩效时,R&D投入显著提升企业价值;反之,实际绩效高于期望绩效则导致其减弱,甚至丧失价值效应。 展开更多
关键词 异质性 家族企业 r&d投入 企业价值 企业行为理论
下载PDF
融资约束、信息披露与R&D投资 被引量:20
15
作者 郑毅 徐佳 《经济与管理》 CSSCI 2018年第1期46-53,共8页
以2011—2015年深市A股上市公司的数据为研究样本,基于研发投资具有异质性的视角,实证分析融资约束、信息披露与我国企业R&D投资的关系。研究结果表明:中国A股深市主板上市公司存在一定程度的融资约束,选择渐进式创新企业的融资约束... 以2011—2015年深市A股上市公司的数据为研究样本,基于研发投资具有异质性的视角,实证分析融资约束、信息披露与我国企业R&D投资的关系。研究结果表明:中国A股深市主板上市公司存在一定程度的融资约束,选择渐进式创新企业的融资约束与R&D投资显著负相关,选择突变式创新企业的融资约束与R&D投资无显著性关系。信息披露对渐进式创新企业的融资约束与R&D投资有显著的正向调节作用,对突变式创新企业的融资约束与R&D投资有显著的负向调节作用,即信息披露质量的提高,有利于企业进行渐进式创新,对突变式创新企业起到负向作用。 展开更多
关键词 r&d投资 融资约束 异质性 信息披露
下载PDF
风险投资介入、投资策略与企业异质R&D创新——基于创业新兴指数样本公司的实证研究 被引量:9
16
作者 李云鹤 王文婷 《科技进步与对策》 CSSCI 北大核心 2014年第21期76-82,共7页
利用创业新兴指数样本公司,实证考察了风险投资介入及其投资策略对企业异质研发创新的影响。结果表明:我国风险投资介入并未对企业异质研发创新产生显著影响;风险投资持股比重增大能显著促进公司常规式研发创新,而对探索式研发创新无显... 利用创业新兴指数样本公司,实证考察了风险投资介入及其投资策略对企业异质研发创新的影响。结果表明:我国风险投资介入并未对企业异质研发创新产生显著影响;风险投资持股比重增大能显著促进公司常规式研发创新,而对探索式研发创新无显著促进效果;联合投资策略能够促进公司常规式研发创新,而对公司探索式研发创新的促进作用并不显著;单独投资策略对公司异质研发创新的促进作用不明显。这表明,我国风险投资对战略性新兴产业常规式创新具有一定的促进作用,但对探索式创新的促进效果不明显。 展开更多
关键词 风险投资 联合投资策略 单独投资策略 异质r& d创新
下载PDF
异质性视角下的R&D企业投入、政府资助与创新绩效——基于微观面板的计数模型实证研究 被引量:31
17
作者 张凤兵 王会宗 《经济与管理评论》 CSSCI 北大核心 2019年第2期80-92,共13页
从产权异质性视角出发,选择标准负二项回归为主的计数模型,运用山东省906家省级认定高新技术企业跨越4年的3624组微观非平衡面板数据,对R&D企业投入、政府投入与创新绩效的关系进行实证研究。结果表明:(1)企业R&D人员投入对专... 从产权异质性视角出发,选择标准负二项回归为主的计数模型,运用山东省906家省级认定高新技术企业跨越4年的3624组微观非平衡面板数据,对R&D企业投入、政府投入与创新绩效的关系进行实证研究。结果表明:(1)企业R&D人员投入对专利产出存在显著的正效应,R&D经费投入的正效应不显著但对发明专利存在显著正向影响;(2)R&D政府资助对专利产出尤其是发明专利产出存在显著正效应,对实用新型专利和外观设计专利产出影响不显著;(3)R&D政府资助、企业年龄和规模对创新产出存在"倒U"型影响但都处于门槛值左侧;(4)政府激励政策强化对企业创新有显著影响,企业创新活动日趋活跃。 展开更多
关键词 异质性 r&d企业投入 r&d政府资助 创新绩效 标准负二项回归
下载PDF
上市公司高管团队特征与R&D投资研究 被引量:32
18
作者 文芳 《山西财经大学学报》 CSSCI 2008年第8期77-83,共7页
以中国上市公司1999~2006年的研发数据为样本,从公司高管团队人口特征和团队的异质性两个维度。实证检验了样本公司高管团队特征对公司R&D投资强度的影响。结果发现,高管团队规模、团队平均受教育水平、平均任期都与公司研发投资强... 以中国上市公司1999~2006年的研发数据为样本,从公司高管团队人口特征和团队的异质性两个维度。实证检验了样本公司高管团队特征对公司R&D投资强度的影响。结果发现,高管团队规模、团队平均受教育水平、平均任期都与公司研发投资强度之间显著正相关,团队的平均年龄与公司研发投资强度之间显著负相关。并且发现,控股股东类型不同。高管团队特征对公司R&D投资强度的影响也不同。 展开更多
关键词 高管团队 r&d投资 人口特征 异质性
下载PDF
中国对RCEP框架内13国OFDI效率评价研究及影响因素分析 被引量:10
19
作者 田泽 宋瑞杰 杨婧怡 《工业技术经济》 北大核心 2021年第11期94-101,共8页
本文采用随机前沿引力模型,在RCEP框架内实证分析了2014~2019年中国对13个国家OFDI前沿水平和效率损失的影响因素,在此基础上,对实测的OFDI效率进行了多维度评价和分析。结果表明:(1)中国与东道国的总体经济规模及经济发展水平都对OFDI... 本文采用随机前沿引力模型,在RCEP框架内实证分析了2014~2019年中国对13个国家OFDI前沿水平和效率损失的影响因素,在此基础上,对实测的OFDI效率进行了多维度评价和分析。结果表明:(1)中国与东道国的总体经济规模及经济发展水平都对OFDI前沿水平有正向影响,而东道国技术研发水平会阻碍OFDI前沿水平的提高;(2)东道国产权保护度、法治水平、政府诚信度、商业自由度和投资自由度与OFDI效率正相关,东道国贸易开放度、宏观经济稳定度和劳动力市场效率与OFDI效率负相关,而东道国金融自由度的积极效用并不显著;(3)观测期内中国对13国投资效率总体偏低但有所改善,投资潜力仍亟待释放,对外投资总体回归理性且战略资产寻求型投资的比重增加。最后分别从宏观和微观角度提出有针对性的对策建议。 展开更多
关键词 rCEP 对外直接投资 投资潜力 随机前沿引力模型 区域异质性 投资区位选择
下载PDF
高管团队垂直对异质性与R&D投资行为研究——基于生物医药行业的实证分析 被引量:9
20
作者 郭葆春 刘艳 《科技管理研究》 CSSCI 北大核心 2015年第21期35-40,共6页
基于高层梯队理论和相似-吸引范式,将职位层级视为高管团队特征的一个重要因素,探讨高管团队中垂直对人口特征差异与生物医药上市公司R&D投资倾向的关系。研究发现:总经理-高管年龄异质性、教育水平异质性均与R&D投资强度负相关... 基于高层梯队理论和相似-吸引范式,将职位层级视为高管团队特征的一个重要因素,探讨高管团队中垂直对人口特征差异与生物医药上市公司R&D投资倾向的关系。研究发现:总经理-高管年龄异质性、教育水平异质性均与R&D投资强度负相关;总经理-高管任期异质性、职业背景异质性与R&D投资强度正相关。此外,管理费用率、资产负债率、总经理兼任董事长与R&D投资强度正相关,公司规模与R&D投资强度负相关。最后对生物医药企业合理配置高管团队以及促进和优化R&D投资等方面提出实践建议。 展开更多
关键词 r&d投资 垂直对异质性 人口特征 生物医药行业
下载PDF
上一页 1 2 23 下一页 到第
使用帮助 返回顶部