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1.
植物抗盐胁迫研究进展   总被引:3,自引:0,他引:3  
盐胁迫严重制约了农业生产,解析盐胁迫机理受到关注。随着抑制消减杂交和基因表达序列分析等大规模表达基因鉴定技术在抗盐研究中的应用,盐碱胁迫下功能基因的获得量迅速增加。综述了近年来在酵母、拟南芥、水稻等生物上利用基因芯片等方法进行抗盐机理研究取得的成果,并介绍了结合系统生物学的方法进行抗盐研究取得的进展,以及植物抗盐胁迫研究的发展前景。  相似文献   

2.
甘蔗转基因研究进展   总被引:1,自引:0,他引:1  
对利用基因工程技术进行甘蔗遗传转化的研究进展进行综述,分别阐述了部分国家在甘蔗转基因研究工作中取得的成果,从研究方法和方向上分析了甘蔗转基因研究的前景及其在蔗糖产业发展中的重要意义。  相似文献   

3.
During the past two decades, Iran has experienced a noteworthy growth in its biomedical research sector. At the same time, ethical concerns and debates resulting from this burgeoning enterprise has led to increasing attention paid to biomedical ethics. In Iran, Biomedical research ethics and research oversight passed through major periods during the past decades, separated by a paradigm shift. Period 1, starting from the early 1970s, is characterized by research paternalism and complete reliance on researchers as virtuous and caring physicians. This approach was in concordance with the paternalistic clinical practice of physicians outside of research settings during the same period. Period 2, starting from the late 1990s, was partly due to revealing of ethical flaws that occurred in biomedical research in Iran. The regulatory and funding bodies concluded that it was not sufficient to rely solely on the personal and professional virtues of researchers to safeguard human subjects' rights and welfare. The necessity for independent oversight, emphasized by international declarations, became obvious and undeniable. This paradigm shift led to the establishment of research ethics committees throughout the country, the establishment of academic research centers focusing on medical ethics (MEHR) and the compilation of the first set of national ethical guidelines on biomedical research–one of the first and most important projects conducted by and in the MEHR. Although not yet arrived, ‘period 3’ is on its way. It is predictable from the obvious trends toward performance of high‐quality clinical research and the appearance of a highly educated new generation, especially among women.  相似文献   

4.
KJ 85-06项目是“八五”期间由中国科学院资助的最大的生态学研究计划.19个研究所、20个试验站、530余名科技人员参加了该项计划,5年总经费1000万元.研究工作取得了重大进展,迄今已发表论文450余篇、专着3部,尚有大量论文与多部专着将陆续出版.本文简要介绍了有关主要研究进展,并就生态系统优化管理研究和生态过程、人类活动影响联网研究提出了两点主张.  相似文献   

5.
Optimal nutrition is critical for human development and economic growth. Sub-Saharan Africa is facing high levels of food insecurity and only few sub-Saharan African countries are on track to eradicate extreme poverty and hunger by 2015. Effective research capacity is crucial for addressing emerging challenges and designing appropriate mitigation strategies in sub-Saharan Africa. A clear understanding of the operating environment for nutrition research in sub-Saharan Africa is a much needed prerequisite. We collected data on the barriers and requirements for conducting nutrition research in sub-Saharan Africa through semi-structured interviews with 144 participants involved in nutrition research in 35 countries in sub-Saharan Africa. A total of 133 interviews were retained for coding. The main barriers identified for effective nutrition research were the lack of funding due to poor recognition by policymakers of the importance of nutrition research and under-utilisation of research findings for developing policy, as well as an absence of research priority setting from within Africa. Current research topics were perceived to be mainly determined by funding bodies from outside Africa. Nutrition researchers argued for more commitment from policymakers at national level. The low capacity for nutrition research was mainly seen as a consequence of insufficient numbers of nutrition researchers, limited skills and a poor research infrastructure. In conclusion, African nutrition researchers argued how research priorities need to be identified by African stakeholders, accompanied by consensus building to enable creating a problem-driven national research agenda. In addition, it was considered necessary to promote interactions among researchers, and between researchers and policymakers. Multidisciplinary research and international and cross-African collaboration were seen as crucial to build capacity in sub-Saharan nutrition research.  相似文献   

6.
A postal questionnaire study was carried out in an urban general practice to determine the effect of the introductory letter being sent by the participants'' own general practitioner compared with that from a letter sent directly from a research unit. By sequential sampling 409 individuals aged between 40 and 59 were assigned to one of two groups. The people in one group were written to by their own general practitioner and those in the other by a doctor from a research unit. Husbands and wives were paired and were always sent the same letter. A second letter was sent to nonresponders after one month. The response rate to the general practitioner was significantly higher than that to the doctor in the research unit (85% compared with 75%) and differed by age and sex. The results have important implications for other research workers and suggest that general practitioners are in a key position in the conduct of medical and epidemiological research.  相似文献   

7.
The aim of this article is to put into critical perspective the empirical findings on secrecy and withholding in research. In other words, by taking existing empirical literature into account, it is intended that a crucial question is answered: Is secrecy and withholding in research harmful or innocuous to science? To understand how secrecy and withholding in research have affected academic science, empirical studies have been placed in the wider context of Mertonian underpinnings of the anticommons threat. The turning point in testing the effects of secrecy and withholding of data and material on scientific research was marked by statistical studies based on surveys and bibliometric measures. These two types of empirical studies have given answers to the basic question since academia was threatened by different modes of practicing science.  相似文献   

8.
9.
目的:探讨瑞舒伐他汀对冠心病患者血脂水平以及颈动脉粥样硬化斑块硬化程度的影响。方法:选择2013年2月至2014年12月我院收治的132例冠心病患者作为研究对象,将其随机分为研究组(66例)和对照组(66例),研究组应用瑞舒伐他汀(rosuvastatin calcium,RC)治疗,对照组采用常规药物治疗,观察和比较两组患者的血脂水平变化情况及颈动脉粥样硬化斑块硬化(IMT)程度的改善情况。结果:两组的总胆固醇(total c holesterol,T C)、低密度脂蛋白胆固醇(Low density lipoprotein cholesterol,LDL-C)、甘油三酯(triglyceride,T G)水平较治疗前均有降低,高密度脂蛋白胆固醇(High density lipoprotein cholesterol,HDL-C)水平较治疗前有升高,研究组变化更显著,组间差异有统计学意义(P0.05)。两组颈动脉粥样硬化斑块硬化程度较治疗前有改善,研究组优于对照组,差异有统计学意义(P0.05)。研究组与对照组治疗总有效率分别为98.5%、71.2%,差异有统计学意义(P0.05)。结论:瑞舒伐他汀能够有效降低冠心病患者的血脂水平,并能改善其颈动脉粥样硬化的程度。  相似文献   

10.
An effective bibliometric analysis based on the Science Citation Index (SCI) published by the Institute of Scientific Information (ISI) was carried out to identify wetland research between 1991 and 2008. The objective was to conduct a quantitative and qualitative analysis for global trends of wetland-related research. The characteristics related to publications were analyzed. The results showed the significant wetland research issues in the SCI database. From 1991 to 2008, the annual number of journal articles published and the number of articles cited to wetland research increased more than sixfold and ninefold respectively. The USA produced the most single-country articles and international collaborative articles, followed by Canada and UK. The results also showed the significant wetland research issues in SCI database. The most frequently used words were: “water” (or “water quality”), which ranked 3rd, 7th, and 3rd according to the word in article title, author keyword, and keyword plus analysis, respectively. Constructed wetland biodiversity became more active in wetland research. The keywords “constructed wetland” and “constructed wetlands” ranked 58th and 12th in 1991–1996, while they ranked 5th and 4th in 2003–2008; the author keyword “biodiversity” ranked 45th in 1991–1996, while it ranked 23rd in 1997–2002, and 14th in 2003–2008; and keyword plus “diversity” ranked 93rd in 1991–1996, while it ranked 20th in 1997–2002, and 17th in 2003–2008. Moreover, it was proved that article title, author keyword, and keyword plus analysis methods were effective approaches for mapping wetland research. Popular wetland research issues and wetland research changes were also identified by statistical analysis.  相似文献   

11.
Philosophers and historians of biology have argued that genes are conceptualized differently in different fields of biology and that these differences influence both the conduct of research and the interpretation of research by audiences outside the field in which the research was conducted. In this paper we report the results of a questionnaire study of how genes are conceptualized by biological scientists at the University of Sydney, Australia. The results provide tentative support for some hypotheses about conceptual differences between different fields of biological research.  相似文献   

12.
中国园林生态学发展综述   总被引:2,自引:0,他引:2  
于艺婧  马锦义  袁韵珏 《生态学报》2013,33(9):2665-2675
运用文献计量等方法对已有科研成果进行统计分析,结果表明:中国近50年园林生态学科领域科研发展经过了起步探索(1962-1981)、缓慢发展(1982-2001)、快速发展(2002-2011)3个时期,园林生态学作为生态学一个新的分支学科,于20世纪90年代末初见端倪,作为一门新兴独立的应用生态学分支学科于21世纪初已基本形成.中国园林生态学领域的研究包括园林生态系统中生物与环境相互作用关系问题、人与环境相互作用关系问题以及园林生态系统与其他生态系统之间相互作用关系问题.当代园林生态研究主要有生态效益研究、生物与环境研究、人的需求与行为研究、生态规划与生态管理研究4个方面,目前园林生态学研究主要侧重生物与环境研究和生态效益研究,两方面的研究成果占总体研究成果的76.3%.不同研究方面也有各自的侧重点,如生物与环境研究侧重对植物的研究,生态效益研究侧重净化环境、水土保持和防灾减灾,生态规划与生态管理研究则侧重生态规划与设计.对四个研究方面的论文主题词检索和高频主题关键词的分布进行统计,结果显示,研究的热点有多样性、群落、水土保持、防灾避险、净化环境、生态规划与设计等.对CNKI中4个研究方面成果中获基金资助项目论文进行统计(不排重),总体成果中基金项目论文所占比重为10.8%,国家和地方基金是园林生态学科研基金资助的主要来源,基金论文比例之和达到85.4%,且国家和地方基金资助论文较多的是“生态与环境研究”和“生态效益研究”,合计占基金论文79.1%.SCI-E中收录的文献基金论文率为47.1%,是CNKI数据库收录的文献基金论文率的4.3倍,且国际基金是基金论文的主要资助来源之一,说明中国园林生态学领域部分科研成果得到国际学界关注.基于CNKI相关主题词统计,“园林生态学”的研究成果只有“景观生态学”的1%,“城市生态学”的8.3%,“园林生态学”学科系统理论研究在相关生态学科研究中所占比重很低,其理论和方法研究还较薄弱.今后在进一步完善学科理论体系、持续开展生态效益和园林植物研究的同时,为更好地研究和解决人-自然复合生态系统问题,提供更多的科学理论支撑,还需拓展交叉生态心理学或环境心理学等其他相关理论,更多地关注人与环境互相作用关系以及生态规划与生态管理等方面的研究,既使环境更好地满足人的行为需求,也使人认识到改变一些行为能更好地保护环境.  相似文献   

13.
This is a review of the activities of what rapidly became the leading plant nematology department in the world, based in what was at that time not only the most important but also the most distinguished agricultural research station in the world. We first briefly review the research done in the period under each head of department before recording in more detail some of the long‐term research programmes, including work on potato cyst nematode hatching factors, chemical control and biological control. These strong research activities flourished until the radical funding constraints that were introduced nationally following release of the Rothschild Report in 1973 forced the adoption of various management actions at research stations. The changed pattern of research funding systems, which evolved gradually from 1973 onwards, resulted in a different style of research collaboration and changes in research focus by institutes and their staff. It became fashionable for institutes to have mission statements and these were changed frequently by directors due to the need to respond to funding possibilities. Successive severe and progressive reductions in staffing and, inevitably, outputs culminated in the complete cessation of nematology research at Rothamsted in 2013, even though cutting edge work on biological control and molecular interactions between nematodes and their plant hosts was still being carried out.  相似文献   

14.
中国汉族群体vWF基因40内含子VNTR   总被引:2,自引:0,他引:2  
本文将Amp-FLP与RFLP结合起来,检测vWF基因40内含子VNTR。调查长沙地区156名无亲缘关系汉族人,发现vWF基因40内含子VNTR基因136个。基因型152个,全部为杂合子,分布符合Hardy-Weinberg平衡定律。此VNTR杂合率为0.9884,PIC为0.9883,是现已检出Amp-FLP中多态性最高的遗传标记。家系分析显示VNTR无遗传重组,依照常染色体共显性遗传。用高分辨  相似文献   

15.
68A realistic research experience is beneficial to undergraduate students, but it is often difficult for liberal arts colleges to offer this opportunity. We describe two approaches for developing and maintaining an interdisciplinary research program at small colleges. An active and continuing involvement of an individual with extensive research experience is an essential element in both. One model was developed by the faculty of Taylor University, Upland, IN and a research scientist who had retired from a major university to join the Taylor faculty as their first Research Professor. The school's Science Research Training Program was initially funded by a modest endowment provided by interested alumni and by extramural grants awarded to the Research Professor and to the institution; the program now enjoys significant funding from diverse sources. Taylor is not located near any large research university and consequently supplies all resources required for the experiments and stipends for students pursuing projects full-time during the summer. The second model was developed by the faculty at Asbury College in Wilmore, KY, working with a scientist having a full-time appointment at the University of Kentucky and a part-time appointment at the college. In this approach, Asbury faculty may place their students for a period of training, often during the summer, in a laboratory of a cooperating host faculty at the University of Kentucky or other institution. The host faculty funds the research and pays a stipend to those students who work full-time during the summer. Relationships established between faculty at the College and at the University of Kentucky have been mutually beneficial. The success of both programs is evidenced by the students' presenting their data at state and national scientific meetings, by their publishing their results in national journals, and by the undergraduate school faculty developing independent research programs.  相似文献   

16.
【背景】全球气候变暖导致的冻土融化加速了微生物对土壤有机碳的降解,产生的温室气体在一定程度上加剧了温室效应,对全球气候变化形成正反馈作用。【目的】本文针对国内外冻土微生物研究的热点和发展趋势进行分析比较,旨在归纳、总结并为今后该领域的研究和发展提供参考和依据。【方法】利用Web of Science核心合集数据库和CNKI数据库检索,运用BIBExcel软件生成高频关键词的共词矩阵,使用UCINET和NetDraw软件完成高频词的网络可视化图谱,并通过SPSS软件实现高频词的聚类分析。【结果】共检索到与冻土微生物相关的国内外文献839篇,其中国外文献713篇、中文文献126篇,国外的发文量和增长率显著高于国内。从高频关键词和共现网络视图上看,国外偏重气候变化、温室气体及微生物群落变化之间的作用关系研究,而国内更偏向于冻土微生物多样性的研究。聚类分析表明,国外研究主要以微生物对有机碳的降解作用及对冻土区乃至全球的影响为主,此外还涉及以冻土微生物为研究对象的火星生命的探究。国内研究主要以冻土微生物多样性、甲烷排放和微生物对污染的降解作用为重点。【结论】国内外对于冻土微生物的研究态势存在异同...  相似文献   

17.
The purpose of this study was to explore the internal mechanism of lung cancer under the action of caspase recruitment domain-containing protein 9 (CARD9) and immunosuppressive cells myeloid-derived suppressor cells (MDSCs) in the Lewis lung cancer mice model. In this research, mice were selected as research objects, and the mechanism of CARD9 and immunosuppressive cells MDSCs in lung cancer was studied by experimental methods such as mRNA expression level, HE staining of tumor cells, and electron microscopy. The results showed that CARD9 regulated lung cancer by controlling the working state of immunosuppressive cells MDSCs and its downstream product indoleamine 2, 3-dioxygenase (IDO). The study confirmed the tumor regulatory mechanism of CARD9-MDSCs-NF-KB-IDO in MDSCs under tumor environment. In summary, the mechanism of CARD9 and immunosuppressive cells MDSCs in lung cancer was to achieve the goal of tumor control through the control of downstream product IDO. There are still some shortcomings in the research process, but the research results still provide some guidance for future research. Therefore, it is a research topic with practical significance.  相似文献   

18.

Background

Organizational context plays a central role in shaping the use of research by healthcare professionals. The largest group of professionals employed in healthcare organizations is nurses, putting them in a position to influence patient and system outcomes significantly. However, investigators have often limited their study on the determinants of research use to individual factors over organizational or contextual factors.

Methods

The purpose of this study was to examine the determinants of research use among nurses working in acute care hospitals, with an emphasis on identifying contextual determinants of research use. A comparative ethnographic case study design was used to examine seven patient care units (two adult and five pediatric units) in four hospitals in two Canadian provinces (Ontario and Alberta). Data were collected over a six-month period by means of quantitative and qualitative approaches using an array of instruments and extensive fieldwork. The patient care unit was the unit of analysis. Drawing on the quantitative data and using correspondence analysis, relationships between various factors were mapped using the coefficient of variation.

Results

Units with the highest mean research utilization scores clustered together on factors such as nurse critical thinking dispositions, unit culture (as measured by work creativity, work efficiency, questioning behavior, co-worker support, and the importance nurses place on access to continuing education), environmental complexity (as measured by changing patient acuity and re-sequencing of work), and nurses' attitudes towards research. Units with moderate research utilization clustered on organizational support, belief suspension, and intent to use research. Higher nursing workloads and lack of people support clustered more closely to units with the lowest research utilization scores.

Conclusion

Modifiable characteristics of organizational context at the patient care unit level influences research utilization by nurses. These findings have implications for patient care unit structures and offer beginning direction for the development of interventions to enhance research use by nurses.  相似文献   

19.
I. Ferrari 《Hydrobiologia》1976,51(3):245-257
The evolution of some limnological parameters during the ice cover period was studied in a mountain lake in the Northern Apennines: Lago Santo Parmense (1507 m a.s.l.; maximum depth 22.5 m). The changes in the biomass and production rate of the phytoplankton were analyzed in relation to the changes in the various physical, chemical and biological parameters (the thickness of the ice cover; the contents of dissolved oxygen, orthophosphate phosphorus, total phosphorus and other nutrients; the zooplankton biomass). The research was carried out in winter 1973 and 1974. A comparison was made with other mountain lakes with morphometric and trophic characteristics similar to those of Lago Santo Parmense.This research was in part supported by a grant (No. 74.00734.04) of Consiglio Nazionale delle Ricerche, ItalyThis research was in part supported by a grant (No. 74.00734.04) of Consiglio Nazionale delle Ricerche, Italy  相似文献   

20.
青藏铁路温性草原区铁路运营对啮齿动物群落结构的影响   总被引:5,自引:0,他引:5  
以青藏铁路海晏段的温性草原区为研究地点,通过铗日法确定距离铁路不同距离的区域中啮齿动物的种群密度和群落结构,分析啮齿动物群落结构与植物群落结构之间的关系,探讨温性草原区铁路运营对啮齿动物群落结构的影响。结果表明,研究区域内所捕获的啮齿动物有甘肃鼠兔、五趾跳鼠、长尾仓鼠和灰仓鼠;从1984 年铁路投入运营以来,没有发现铁路运营带来新物种的入侵;啮齿动物的种群密度和群落结构在距离铁路不同距离的样带之间有明显的不同,在铁路路基附近的种群密度、物种数、多样性指数均明显高于距离铁路0.5 km和1 km的区域,而均匀性指数在路基附近最小;在距离铁路不同距离的区域中植物群落的特征没有明显差异,啮齿动物群落特征与植物群落特征之间没有明显的相关性。引起铁路路基附近啮齿动物种群密度、物种数、多样性指数偏高的原因可能是铁路修建与运营为啮齿动物提供了合适的生存环境与额外的食物资源。因此,铁路建设及运营对啮齿动物的群落结构有一定程度的影响。  相似文献   

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