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1.
The yeast phase of ten P. brasiliensis isolates were studied to characterize their growth pattern, morphology and ultrastructure. Growth curves were determined after counts of total and viable fungi units (FU) during 20 days. Three growth patterns were observed: slow, reaching approximately 10–30× 106 FU/tube (Pb 18, Pb 265 and PB 2); intermediate, reaching 60–150×106 FU/tube (IVIC Pb 9, IVIC Pb 267, Pb SN, Pb Vitor and Pb Campo Grande) and fast, reaching 180–370×106 FU/tube (Pb 2052 and Pb 192). The highest percentage of viable cells occurred on the 6th day of culture for Pb 192, Pb Campo Grande, Pb 2052 and IVIC Pb 9; on the 8th day for Pb Vitor, Pb SN, Pb 18 and IVIC Pb 267; on the 10th day for Pb 265 and on the 12th day of culture for Pb 2. Mean generation times varied from approximately 21.2 (Pb 2052) to 102.6 hours (Pb 265). The isolates showed similar morphology, except IVIC Pb 267 which did not present a typical yeast-phase at 35°C and the two fast-growing isolates (Pb 2052 and Pb 192) that presented smaller cell sizes and less tendency to clump. The ultrastructure of the isolates was similar: the cell walls presented a width of 0.1 to 0.2 °; the mitochondria presented few cristae and had equivalent patterns of distribution and morphology; the endoplasmic reticulum was scanty, presenting narrow cisternae; the vacuoles, empty or filled with electrondense material, were numerous and two to five nuclei with pores were constantly observed.  相似文献   

2.
Summary The Scientific Research Center of Yucatán (CICY, for its Spanish acronym) was founded in November 1979 as part of an effort to decentralize scientific activities from Mexico City. Several of the research programs carried out at CICY make use of plant tissue culture techniques for their development. For this article, we have reviewed results obtained in research projects oriented towards basic plant biology questions, as well as towards the micropropagation of economically important species, and the production of secondary metabolites.  相似文献   

3.
《应用发育科学》2013,17(4):228-234
Researchers are increasingly recognizing the importance of disseminating the results of research to a wider audience than other researchers. Dissemination, or "giving child development knowledge away," is important to maintaining a national commitment to the support of research, and it is essential if we are to develop policies and programs that effectively promote the development of children and youth. In this article, I review several of the most innovative and timely efforts to give child development knowledge away. Some dissemination projects result directly from university community partnerships; others are separate undertakings. In both cases, however, partnerships are key; there is a clear role for partnerships in furthering dissemination.  相似文献   

4.
Previously we have reported that two sublines of the YAC lymphoma selected for reduced expression of H-2a and Moloney-virus determined cell-surface (MCSA) antigens are, in contrast to YAC, allotransplantable in H-2-incompatible recipients, and resistant to rejection by preimmunized semisyngeneic hosts. A third YAC variant with reduced MCSA but unchanged H-2-antigen expression, was not allotransplantable and showed only a slight decrease in its immunosensitivity in preimmunized semisyngeneic hosts in vivo. This suggested that H-2-antigen expression may be more important than MCSA expression for recognition and rejection by semisyngeneic mice. We have now tested the sublines expressing low H-2a for their in vitro sensitivity to humoral and cell-mediated lysis. — The variants were more resistant than YAC to complement lysis by anti-H-2a, anti-MCSA, anti-Thy 1.2 and antispecies sera. Absorption tests with antispecies serum indicated that the decreased cytolytic sensitivity of the variants was not related to the concentration of the relevant antigens, which was similar to that of the original YAC tumor. As expected from the low amount of H-2a the variants showed a decreased sensitivity to the killing effect of allogeneic cytotoxic T lymphocytes (CTL). They were also lysed to a lesser extent than YAC by semisyngeneic CTL, probably directed against virally determined antigens. However, they were also less sensitive to lysis by natural killer (NK) cells, although NK lysis is probably unrelated to MHC expression. In conclusion, our selection for reduced H-2-expression appears to have resulted in the isolation of variants with a generally increased resistance to various humoral and cell-mediated lytic functions.On leave from Instituto Venezolano de Investigaciones Cientificas (IVIC), Caracas, Venezuela.  相似文献   

5.
邹晓沨  涂娟  吴建元  秦俊  黄建英 《生物磁学》2013,(27):5377-5380
本文就国内涉及人的医学科研项目伦理审查现状进行了简要介绍,并结合武汉大学中南医院医学伦理委员会近年来伦理审查的工作实际,对涉及人的医学科研项目伦理审查中存在的共性问题进行了初步探讨,提出管理部门和伦理委员会应加强对研究人员伦理知识的宣传教育,加强科研项目伦理行为的过程监督,保护受试者权益,保证医学科研的健康发展。  相似文献   

6.
In recent years, human genetic research has developed rapidly, and the cost of sequencing and computational technology continues to decline. This research has also been pushed forward by a major organizational innovation: the development of large, open-access databases of human gene sequences or biospecimens known as community resource projects. This article describes a challenge for the governance of these projects: conceptions of population vary significantly across organizational contexts. This makes it difficult to manage risk appropriately, as measures intended to address hazards to one kind of population may be inadequate for others. Unstable conceptions of population may also make it difficult to identify the stakeholders interested in the governance of these projects. This argument is developed by examining two cases, the International HapMap Project and 1000 Genomes Project, which make use of at least six distinct conceptions of population in different organizational segments.  相似文献   

7.
Tissue banking is a complex operation concerned with the organisation and coordination of all the steps, that is, from donor selection up to storage and distribution of the final products for therapeutic, diagnostic, instruction and research purposes. An appropriate quality framework should be established in order to cover all the specific methodology as well as the general aspects of quality management, such as research and development, design, instruction and training, specific documentation, traceability, corrective action, client satisfaction, and the like. Such a framework can be obtained by developing a quality management system (QMS) in accordance with a suitable international standard: ISO 9001:2000. This paper presents the implementation process of the tissue bank QMS at the Instituto Nacional de Investigaciones Nucleares in Mexico. Objective: The objective of the paper is to share the experience gained by the tissue bank personnel [radiosterilised tissue bank (BTR)] at the Instituto Nacional de Investigaciones Nucleares (ININ, National Institute of Nuclear Research), during implementation of the ISO 9001:2000 certification process. At present, the quality management system (QMS) of ININ also complies with the Mexican standard NMX-CC-9001:2000. The scope of this QMS is Research, Development and Processing of Biological Tissues Sterilised by Gamma Radiation, among others.  相似文献   

8.
9.
姜广顺  李京芝 《兽类学报》2021,41(5):604-613
目前全球物种正以前所未有的速度灭绝,对野生动物栖息地开展有效的评估与科学的保护是阻止濒危物种走向灭绝,保持其可持续生存与发展的重要前提和手段。本文针对我国的食肉类、有蹄类、灵长类、小型兽类、海洋兽类5个类别的濒危兽类,综述了其栖息地评估与保护研究进展的现状和成果,对相关学术成果进行了归纳与分析,以期为栖息地的科学保护与管理梳理出系统、可供借鉴的研究方法和技术手段,并对其理论和技术的挑战进行了展望,提出了我国濒危兽类栖息地评估和保护研究应走向整体化、定量化、智能化,以及多学科交叉融合应用的“精准化”发展方向,为国家生态建设工程的有效实施提供重要技术支撑。  相似文献   

10.
Engaging school students in wildlife research through citizen science projects can be a win–win for scientists and educators. Not only does it provide a way for scientists to gather new data, but it can also contribute to science education and help younger generations become more environmentally aware. However, wildlife research can be challenging in the best of circumstances, and there are few guidelines available to help scientists create successful citizen science projects for school students. This paper explores the opportunities and challenges faced when developing school‐based citizen science projects in wildlife research by synthesising two sources of information. First, we conducted a small, school‐based citizen science project that investigated the effects of supplementary feeding on urban birds as a case study. Second, we reviewed the literature to develop a database of school‐based citizen science projects that address questions in wildlife ecology and conservation. Based on these activities, we present five lessons for scientists considering a school‐based citizen science project. Overall, we found that school‐based citizen science projects must be carefully designed to ensure reliable data are collected, students remain engaged, and the project is achievable under the logistical constraints presented by conducting wildlife research in a school environment. Ultimately, we conclude that school‐based citizen science projects can be a powerful way of collecting wildlife data while also contributing to the education and development of environmentally aware students.  相似文献   

11.
Spherical and osmotically sensitive protoplasts were released from cultures of the yeast-like form of Paracoccidioides basilienisis strain IVIC Pb9 through the action of a mixture of crude enzyme preparations: alpha and beta-glucanases and chitinase, obtained from culture filtrates of Cladosporium resinae, Basidiomycete QM 806 and Streptomyces sp respectively. The highest efficiency of protoplast liberation was achieved when each crude enzyme preparation was used at 1 mg/ml.  相似文献   

12.
The yeast-like forms of six P. brasiliensis strains were characterized and compared using in vitro (growth curve determination) and in vivo (pathogenicity to sensitive inbred mice) criteria. Strains Pb 18 and Pb 265 which behaved similarly in vitro, showing low counts of fungi and long mean generation times, were respectively the most and the least pathogenic strains. Strains Pb 2052 and IVIC Pb 267, which grow abundantly in vitro were, respectively virulent and avirulent. Strains Pb SN and IVIC Pb 9 behaved similarly both in vitro and in vivo displaying an intermediate pattern of virulence and growing conditions.  相似文献   

13.
杜全生  祖岩  洪伟  魏伟 《微生物学报》2020,60(12):2862-2871
国家自然科学基金资助RNA病毒相关基础研究,主要包括病毒溯源、结构与功能、遗传与演化、以及与宿主相互作用等方面,以揭示病毒产生、传播与致病的物质基础与作用机制,为相关疾病的诊断、预防和治疗提供理论基础。本文主要从项目类型、资助经费、人才培养、资助成果等方面,统计了国家自然科学基金RNA病毒相关获资助项目情况,分析本领域项目资助存在的问题,尝试提出未来发展建议。  相似文献   

14.
The purpose of this article is to discuss small-group apprenticeships (SGAs) as a method to instruct cell culture techniques to high school participants. The study aimed to teach cell culture practices and to introduce advanced imaging techniques to solve various biomedical engineering problems. Participants designed and completed experiments using both flow cytometry and laser scanning cytometry during the 1-month summer apprenticeship. In addition to effectively and efficiently teaching cell biology laboratory techniques, this course design provided an opportunity for research training, career exploration, and mentoring. Students participated in active research projects, working with a skilled interdisciplinary team of researchers in a large research institution with access to state-of-the-art instrumentation. The instructors, composed of graduate students, laboratory managers, and principal investigators, worked well together to present a real and worthwhile research experience. The students enjoyed learning cell culture techniques while contributing to active research projects. The institution's researchers were equally enthusiastic to instruct and serve as mentors. In this article, we clarify and illuminate the value of small-group laboratory apprenticeships to the institution and the students by presenting the results and experiences of seven middle and high school participants and their instructors.  相似文献   

15.
《Small Ruminant Research》2010,94(2-3):67-75
This article is a presentation of the local Mediterranean cheese sector and of the several types of projects and initiatives to promote the Mediterranean local cheeses: promotional campaigns, workshops, networks and meetings, regional events (cheeses shows, processing demonstrations, thematic routes, cheese contests, …). The small-scale and farm-made cheeses, mostly with sheep or goat milk, are generally considered a possible vehicle of economic and social development for the less favored rural areas; mountainous areas are seen as holders of local know-how. To support this development, several initiatives and often public supported projects have aimed to promote and improve the valorization of these local small-scale Mediterranean cheeses and their heritage value. The analysis is based mainly on a comparison of projects and initiative in which the authors were involved through several European projects of cooperation. The different situations in the northern and southern areas are considered separately. For each initiative, we particularly focus on the type of organization or institution that has led it: Regional Public Extension, National Park Administration, Universities or Research Centers, Public Organizations, Professional Associations …. We cross them with simple indicators to characterize each regional sector. The initiatives are characterized regarding the coherence and impact of these projects. In several cases, the promotion of local cheeses is not related to a sustainable and coherent strategy of development of production. The interrelations between institutional public projects of regional rural development and the local cheese and animal production systems were studied. This article underlines that such initiatives have to integrate the components of a coherent appropriation of the Mediterranean Cheese heritage and the tensions between technical and cultural approaches.  相似文献   

16.
In an earlier issue of this journal (Volume 1, number 2) we outlined current research projects and graduate training programs in American universities. This article is similar in that it includes relevant data for British universities.  相似文献   

17.
Biomedical research relies increasingly on large collections of data sets and knowledge whose generation, representation and analysis often require large collaborative and interdisciplinary efforts. This dimension of 'big data' research calls for the development of computational tools to manage such a vast amount of data, as well as tools that can improve communication and access to information from collaborating researchers and from the wider community. Whenever research projects have a defined temporal scope, an additional issue of data management arises, namely how the knowledge generated within the project can be made available beyond its boundaries and life-time. DC-THERA is a European 'Network of Excellence' (NoE) that spawned a very large collaborative and interdisciplinary research community, focusing on the development of novel immunotherapies derived from fundamental research in dendritic cell immunobiology. In this article we introduce the DC-THERA Directory, which is an information system designed to support knowledge management for this research community and beyond. We present how the use of metadata and Semantic Web technologies can effectively help to organize the knowledge generated by modern collaborative research, how these technologies can enable effective data management solutions during and beyond the project lifecycle, and how resources such as the DC-THERA Directory fit into the larger context of e-science.  相似文献   

18.
在今天,我们的生存环境面临着诸多挑战,包括气候变化,生物多样性减少,可用于发展的土地资源接近上限等等。面对这些问题,前荷兰首席国家风景园林师德克·西蒙斯认为我们必须关注那些能够改变景观的力量,不管它们是水利工程、旅游业、农业还是新能源。西蒙斯在文中介绍了他的过程导向方法论的思想起点,并通过几个获奖项目阐释了他如何运用这一方法。同时特别强调对生态系统的保护和修复是这个时代最重要的议题之一,也是我们这一代人最重要的使命之一。作为风景园林师,设计结合研究是我们的有力武器。我们不能仅关注眼前工作,还需要用长远的眼光批判地看待整个城市化进程。  相似文献   

19.
This article describes the origins, working practices and various development projects of the HUman Proteome Organisation's Proteomics Standards Initiative (HUPO PSI), specifically, our work on reporting requirements, data exchange formats and controlled vocabulary terms. We also offer our view of the two functional genomics projects in which the PSI plays a role (FuGE and FuGO), discussing their impact on our process and laying out the benefits we see as accruing, both to the PSI and to biomedical science as a whole as a result of their widespread acceptance.  相似文献   

20.
Roads impede animal movement, which decreases habitat accessibility and reduces gene flow. Ecopassages have been built to mitigate this but there is little research with which to evaluate their effectiveness, owing to the difficulty in accessing results of existing research; the lack of scientific rigor in these studies; and the low priority of connectivity planning in road projects. In this article, we suggest that the imperative for improving studies of ecopassage effectiveness is that road ecology research should be included from the earliest stages of road projects onwards. This would enable before-after-control-impact (BACI) design research, producing useful information for the particular road project as well as rigorous results for use in future road mitigation. Well-designed studies on ecopassage effectiveness could help improve landscape connectivity even with the increasing number and use by traffic of roads.  相似文献   

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