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461.
《Microbes and infection / Institut Pasteur》2019,21(5-6):192-201
The Institut Pasteur was created thanks to worldwide generosity with the aim to welcome and treat rabies patients, to provide a place for scientific research and to offer new teaching programs in microbiology. Louis Pasteur invited his main collaborators, who had accompanied him during his previous investigations at École Normale Supérieure, to join him in his new institute. They contributed to the principle discoveries of Pasteur, such as the fight against spontaneous generation, the identification of the ferments of putrefaction, the fight against the silk worm disease, the research on wine and beer, and the set-up of the first vaccines against avian cholera, anthrax, swine erysipelas and rabies. There were two scientists, Émile Duclaux and Charles Chamberland, and two medical doctors, Émile Roux, and Joseph Grancher. In addition, two Russian scientists were invited to join the Institute and to head a research laboratory, Élie Metchnikoff and Nikolaï Gamaleïa, the later will finally never join the institute. 相似文献
462.
David Moore 《Mycologist》2006,20(4):152-158
The one place it's almost impossible to find fungi is in the UK National Curriculum for schools. The state of the National Curriculum (NC) is a real concern because the current specifications all contain material on animal and plant comparisons with little or no consideration for the largest group of higher organisms on Earth: Kingdom Fungi. This means that children are missing out on being taught about the importance of an entire Kingdom of higher organisms. To try to compensate for this educational deficiency, the British Mycological Society has taken up the challenge by devising resources teachers can use within the current NC because they address NC topics and also give proper representation to fungi. These resources include specially-produced and ready-to-use lessons and classroom activities, teacher's guides and pupil class sheets, all classroom tested and well received by pupils. But the resources also feature articles published over many years in the Society's journals that need to be brought out of the library archives and made immediately accessible to schools. These resources are available now for free download from the British Mycological Society's new education website at www.fungi4schools.org, which is described in this article. 相似文献
463.
Advances in digital technology and the growth of information networks are revolutionizing human activity. The Internet has been championed as a new tool for environmental improvement. A life-cycle energy analysis of digital libraries, a growing application of information technology, was conducted to test this premise.
Life-cycle models were compared for journal collections in digital and traditional formats. The basis for analysis was the amount of information in a typical scientific journal article (∼12 pages), which is equivalent to 0.97 hr of on-screen reading time. Digital system elements such as servers, routers, laser printers, and computer workstations were modeled. Journal production, delivery, storage, binding, interlibrary loan, and photocopying were examined for the traditional system. Building-related infrastructure, office paper, and personal transportation of the library patron were analyzed for both cases. In all, the study incorporated nearly 30 model elements, 90 input variables, and numerous fixed parameters.
Five primary scenarios were constructed to consider increasing levels of complexity. Scenario 1 assumes only one reading per article (unit of analysis). Additional scenarios assume 1,000 readings and vary the following: laser printing, photocopying, and personal transportation. Energy consumed by the digital collection ranged between 4.10 and 216 MJ. The traditional system realized burdens from 0.55 to 525 MJ. Four significant effects were uncovered: (1) Energy consumption per unit was highly influenced by the number of readings per article. (2) Networking infrastructure by itself had a relatively small effect on total energy consumed by the digital system. (3) When personal transportation was considered, its effects tended to dominate. (4) The impact of making personal copies varied. Photocopying always increased energy consumption, whereas laser printing actually saved energy when it substituted for on-screen reading. 相似文献
Life-cycle models were compared for journal collections in digital and traditional formats. The basis for analysis was the amount of information in a typical scientific journal article (∼12 pages), which is equivalent to 0.97 hr of on-screen reading time. Digital system elements such as servers, routers, laser printers, and computer workstations were modeled. Journal production, delivery, storage, binding, interlibrary loan, and photocopying were examined for the traditional system. Building-related infrastructure, office paper, and personal transportation of the library patron were analyzed for both cases. In all, the study incorporated nearly 30 model elements, 90 input variables, and numerous fixed parameters.
Five primary scenarios were constructed to consider increasing levels of complexity. Scenario 1 assumes only one reading per article (unit of analysis). Additional scenarios assume 1,000 readings and vary the following: laser printing, photocopying, and personal transportation. Energy consumed by the digital collection ranged between 4.10 and 216 MJ. The traditional system realized burdens from 0.55 to 525 MJ. Four significant effects were uncovered: (1) Energy consumption per unit was highly influenced by the number of readings per article. (2) Networking infrastructure by itself had a relatively small effect on total energy consumed by the digital system. (3) When personal transportation was considered, its effects tended to dominate. (4) The impact of making personal copies varied. Photocopying always increased energy consumption, whereas laser printing actually saved energy when it substituted for on-screen reading. 相似文献
464.
Robin Whittemore Ariana Chao Rachel Popick Margaret Grey 《The Yale journal of biology and medicine》2013,86(1):49-62
In response to the childhood obesity epidemic, numerous studies on school-based
Internet obesity prevention interventions have been conducted. The purpose of
this systematic review is to describe, synthesize, and evaluate the research on
school-based Internet obesity prevention programs for adolescents. Medline,
CINAHL, and PsycInfo were searched from January 1995 to August 2012 to locate
relevant studies. Ninety-one reports were initially identified, with 12 meeting
the inclusion criteria. Studies had variable control groups, program content,
and sample characteristics. Though few authors reported on implementation
processes or body mass index (BMI) outcomes, the majority of studies were
effective in improving health behaviors in the short term. Most studies were
judged to have a high or unclear risk of bias in at least two domains, thus the
quality of evidence for this body of literature is moderate. Further research is
needed to examine programs of longer duration, optimal dose and timing of
programs, cost-effectiveness, and mediators and moderators of intervention
outcomes. 相似文献
465.
Donald Newgreen Miranda Grounds Suresh Jesuthasan Hassan Rashidi Mary Familari 《Differentiation; research in biological diversity》2012
The 2nd Royan Institute International Summer School was built around the topic of stem cells and grounding in the discipline of developmental biology. The meeting provided not only direct transfer of technical and intellectual information, the normal process in scientific meetings, but was also a forum for the exchange of personal ideas of science as a creative pursuit. This summer school introduced aspiring young Iranian scientists to international researchers and exposed the latter to a rich culture that highly values learning and education, attested by the confident, intelligent young men and women who asked probing questions and who were eager to participate in the workshops. Hossein Baharvand's dedication and passion for science have led to an impressive record of national and international peer-reviewed publications and an increasing number of students who pursue science in Iran, and shows how the right people can create an environment where good science, good science education and motivation will flourish. This report summarizes some of the activities of the workshop in the Royan Institute and the impressions of the visiting scientists in the wider context of the scientific and cultural heritage of Iran. 相似文献
466.
467.
Gazi Islam 《Dialectical Anthropology》2006,30(1-2):71-89
A participant-observer approach was used to explore an online chat community. The chat room was defined in terms of its construction
and maintenance of speaker identities, and the user-chat room interface was examined with the aim of exploring how notions
of selfhood can be better understood. Chat room audiences were then discussed within the framework of delineating different
levels of virtual audiences and outlining processes by which these different levels interact. Finally, formal and informal
discursive constraints were explored, and conclusions drawn on the ways that chat room users deal with constraints on their
chat activity. Implications for understanding internet communication as well as discourse in general are discussed. 相似文献
468.
Daniel Schien Paul Shabajee Mike Yearworth Chris Preist 《Journal of Industrial Ecology》2013,17(6):800-813
In this study, we use an improved, more accurate model to analyze the energy footprint of content downloaded from a major online newspaper by means of various combinations of user devices and access networks. Our results indicate that previous analyses based on average figures for laptops or desktop personal computers predict national and global energy consumption values that are unrealistically high. Additionally, we identify the components that contribute most of the total energy consumption during the use stage of the life cycle of digital services. We find that, depending on the type of user device and access network employed, the data center where the news content originates consumes between 4% and 48% of the total energy consumption when news articles are read and between 2% and 11% when video content is viewed. Similarly, we find that user devices consume between 7% and 90% and 0.7% and 78% for articles and video content, respectively, depending on the type of user device and access network that is employed. Though increasing awareness of the energy consumption by data centers is justified, an analysis of our results shows that for individual users of the online newspaper we studied, energy use by user devices and the third‐generation (3G) mobile network are usually bigger contributors to the service footprint than the datacenters. Analysis of our results also shows that data transfer of video content has a significant energy use on the 3G mobile network, but less so elsewhere. Hence, a strategy of reducing the resolution of video would reduce the energy footprint for individual users who are using mobile devices to access content by the 3G network. 相似文献
469.
Methods to present three-dimensional (3D) and time series of 3D datasets (4D) are demonstrated using the recent advances
in confocal microscopy and computer visualization. The process of cell sorting during tip formation in the slime mould Dictyostelium discoideum is examined as an example by in vivo confocal microscopy of spectrally different green fluorescent protein (GFP) variants
as reporters of cell-type specific gene expression. Also, cell sorting of the co-aggregating slime mould species D. discoideum and D. mucoroides is observed using a GFP variant and a spectrally distinguishable fluorescent vital stain. The confocal data are handled as
3D and 4D datasets, their processing and the advantages of different methods of visualization are discussed step by step.
Selected sequences of the experiments can be viewed on the Internet, giving a much better impression of the complex cellular
movements during Dictyostelium morphogenesis than printed photographs.
Received: 17 February 1998 / Accepted: 14 June 1998 相似文献
470.
The World Wide Web has become an important resource for public awareness and for educating the world’s population, including
its political leaders, students, researchers, teachers, and ordinary citizens seeking information. Relevant information on
photosynthesis-related web sites is grouped into several categories: (1) group sites, (2) sites by subject, (3) individual
researcher’s sites, (4) sites for educators and students, and (5) other useful sites. 相似文献