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921.
B Bachet C Brassy I Morize E Surcouf J P Mornon B Bodo S Rebuffat 《Journal of molecular biology》1983,170(3):795-796
Trichorzianine A 1 is one of the main components of a mixture of related antibiotic peptides (trichorzianines) produced by the fungus Trichoderma harzianum. Good crystals were obtained and allowed X-ray diffraction up to 0.8 A resolution. The space group is orthorhombic, C222(1), Z = 8, a = 64.8 (1) A, b = 9.33 (3) A, c = 39.9 (1) A. The solvent content is only 12%, preventing a heavy ion diffusion. So, we are trying to obtain the structure by direct methods. 相似文献
922.
Stylianos Serghiou Despina G. Contopoulos-Ioannidis Kevin W. Boyack Nico Riedel Joshua D. Wallach John P. A. Ioannidis 《PLoS biology》2021,19(3)
Recent concerns about the reproducibility of science have led to several calls for more open and transparent research practices and for the monitoring of potential improvements over time. However, with tens of thousands of new biomedical articles published per week, manually mapping and monitoring changes in transparency is unrealistic. We present an open-source, automated approach to identify 5 indicators of transparency (data sharing, code sharing, conflicts of interest disclosures, funding disclosures, and protocol registration) and apply it across the entire open access biomedical literature of 2.75 million articles on PubMed Central (PMC). Our results indicate remarkable improvements in some (e.g., conflict of interest [COI] disclosures and funding disclosures), but not other (e.g., protocol registration and code sharing) areas of transparency over time, and map transparency across fields of science, countries, journals, and publishers. This work has enabled the creation of a large, integrated, and openly available database to expedite further efforts to monitor, understand, and promote transparency and reproducibility in science.This study uses novel open source automated tools to monitor transparency across all 2.75 million open access articles on PubMed Central, discovering that different disciplines, journals and publishers abide by principles of transparency to varying degrees over time. 相似文献
923.
F Mosci P Locci M A Bodo F Fronticelli 《Bollettino della Società italiana di biologia sperimentale》1979,55(15):1445-1448
An eterotopic grafting of their livers has been made between two inbred rats. From 30 to 50 days later the livers has been observed through OM or SEM. In the first case (OM) there was evidence of vacuolar degeneration of liver cells gradually decreasing on the 50th day. In the latter case (SEM) the morphological appearance remained unchanged. 相似文献
924.
Vishwesh V. Kulkarni Venkatesh Kareenhalli Ganesh A. Viswananthan Marc Riedel 《Systems and synthetic biology》2011,5(3-4):97-104
Genetic regulatory networks respond dynamically to perturbations in the intracellular and extracellular environments of an organism. The GAL system in the yeast Saccharomyces cerevisiae has evolved to utilize galactose as an alternative carbon and energy source, in the absence of glucose in the environment. We present a dynamic model for GAL system in Saccharomyces cerevisiae, which includes a novel mechanism for Gal3p activation upon induction with galactose. The modification enables the model to simulate the experimental observation that in absence of galactose, oversynthesis of Gal3p can also induce the GAL system. We then characterize the memory of the GAL system as the domain of attraction of the steady states. 相似文献
925.
The new segmented spongeColospongia ramosa n. sp. is described from Carnian shallow-water limestones of the Western Carpathians (Aggtelekt Karst, Silica Nappe) of North Hungary. This new species occurs also in the Carnian part of the Pantokrator Limestones of Hydra island (Greece).Colospongia ramosa n. sp. differs from other species ofColospongia by the crescent-like chambers and by its branching growth. 相似文献
926.
K. Riedel A. Schroeter P. Liebs J. P. Graba M. Hecker D. Schrapel 《Folia microbiologica》1987,32(2):96-100
The kinetics of extracellular neutral proteinase synthesis by an isogenic stringent (IS58) and a relaxed (IS56) strain ofB. subtilis were compared. The specific enzyme formation rate by the stringent strain was higher than that of the relaxed one. Norvaline
addition (1 mg/mL) induced the formation of pppGpp and ppGpp, respectively, as well as the appearance of extracellular neutral
proteinase activities in cultures of the stringent strain IS58 and a strain with high proteinase production (ZF-178) only.
These correlations support the suggestion that (p)ppGpp are involved in the regulation processes responsible for production
of extracellular neutral proteinases byB. subtilis.
Dedicated to Prof. Dr. F. Mach on the occasion of his 60th birthday. 相似文献
927.
928.
Quantitative Determination of Neuraminidase-Active Foci in Cell Monolayer Cultures Infected with Influenza or Newcastle Disease Virus 总被引:3,自引:2,他引:1
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A synthetic neuraminidase substrate [2-(3'-methoxyphenyl)-N-acetyl-alpha-neuraminic acid] was used to detect myxo- and paramyxovirus replication in tissue culture. This method allowed estimation of viral growth even in the absence of cytopathogenic effects. 相似文献
929.
Susanne Riedel Stefan Widmer Manuel Babbi Serge Buholzer Andreas Grünig Felix Herzog Nina Richner Jürgen Dengler 《植被学杂志》2023,34(5):e13208
Grasslands host a significant share of Europe's species diversity but are among the most threatened vegetation types of the continent. Resurvey studies can help to understand patterns and drivers of changes in grassland diversity and species composition. However, most resurveys are based on local or regional data, and hardly reach back more than eight decades. Here, we publish and describe the Historic Square Foot Dataset, comprising 580 0.09-m2 and 43 1-m2 vegetation plots carefully sampled between 1884 and 1931, covering a wide range of grassland types across Switzerland. We provide the plots as an open-access data set with coordinates, relocation accuracy and fractional aboveground biomass per vascular plant species. We assigned EUNIS habitat types to most plots. Mean vascular plant species richness in 0.09 m2 was 19.7, with a maximum of 47. This is considerably more than the present-day world record of 43 species for this plot size. Historically, species richness did not vary with elevation, differing from the unimodal relationship found today. The data set provides unique insight into how grasslands in Central Europe looked more than 100 years ago, thus offering manifold options for studies on the development of grassland biodiversity and productivity. 相似文献
930.
Morris Riedel Felix Wolf Dieter Kranzlmüller Achim Streit Thomas Lippert 《Cluster computing》2009,12(4):357-372
Computational simulations and thus scientific computing is the third pillar alongside theory and experiment in todays science.
The term e-science evolved as a new research field that focuses on collaboration in key areas of science using next generation
computing infrastructures (i.e. co-called e-science infrastructures) to extend the potential of scientific computing. During
the past years, significant international and broader interdisciplinary research is increasingly carried out by global collaborations
that often share a single e-science infrastructure. More recently, increasing complexity of e-science applications that embrace
multiple physical models (i.e. multi-physics) and consider a larger range of scales (i.e. multi-scale) is creating a steadily
growing demand for world-wide interoperable infrastructures that allow for new innovative types of e-science by jointly using
different kinds of e-science infrastructures. But interoperable infrastructures are still not seamlessly provided today and
we argue that this is due to the absence of a realistically implementable infrastructure reference model. Therefore, the fundamental
goal of this paper is to provide insights into our proposed infrastructure reference model that represents a trimmed down
version of ogsa in terms of functionality and complexity, while on the other hand being more specific and thus easier to implement. The proposed
reference model is underpinned with experiences gained from e-science applications that achieve research advances by using
interoperable e-science infrastructures. 相似文献