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391.
Fei Wang 《Inorganica chimica acta》2010,363(6):1320-3958
Five novel complexes with two pyridine substituted benzotriazole ligands, 1-(2-pyridyl)benzotriazole (L1) and 1-(4-pyridyl)benzotriazole (L2), [Zn(L1)2Cl2] (1), [{Zn(L1)2Cl2}·(L1)2] (2), [Zn(L2)2Cl2] (3), [{Zn(L2)(H2O)3(μ2-SO4)}·H2O] (4), and [{Cd(L2)(H2O)3(μ2-SO4)}·H2O] (5) were synthesized. The details of the structures were characterized by X-ray single crystal analysis, revealing that these complexes were assembled together via supramolecular interaction, such as, hydrogen bonding and π-π interactions. The influence of organic ligands, anions and reaction conditions in the formation of the complexes were investigated. 相似文献
392.
393.
J. E. Beever H. A. Lewin W. Barendse L. Andersson S. M. Armitage C. W. Beattie B. M. Burns S. K. Davis S. M. Kappes B. W. Kirkpatrick R. Z. Ma R. A. McGraw R. T. Stone J. F. Taylor 《Animal genetics》1996,27(2):69-76
A report of the first workshop on the genetic map of bovine chromosome 23 (BTA23) is given. Five laboratories contributed data from 29 loci, including a total 11586 informative genotypes. The combined pedigrees represented 1930 potentially informative meioses. Eighteen of the 29 loci were common to two or more data sets and were used to construct a framework linkage map of BTA23. Twelve of the 18 could be ordered on the linkage map with a likelihood ratio of greater than 1000:1. Thus, a low resolution consensus map was constructed with a high level of support for order. The sex-averaged, female and male maps span 54.5, 52.7 and 55.8 cM, respectively. Sex-specific differences in recombination frequency were identified for eight pairs of framework loci. Average genetic distance between framework loci on the sex-averaged map is 5.0 cM. 相似文献
394.
The theory of optimal foraging predicts abrupt changes in consumer behavior which lead to discontinuities in the functional
response. Therefore population dynamical models with optimal foraging behavior can be appropriately described by differential
equations with discontinuous right-hand sides. In this paper we analyze the behavior of three different Lotka–Volterra predator–prey
systems with optimal foraging behavior. We examine a predator–prey model with alternative food, a two-patch model with mobile
predators and resident prey, and a two-patch model with both predators and prey mobile. We show that in the studied examples,
optimal foraging behavior changes the neutral stability intrinsic to Lotka–Volterra systems to the existence of a bounded
global attractor. The analysis is based on the construction and use of appropriate Lyapunov functions for models described
by discontinuous differential equations.
Received: 23 March 1999 相似文献
395.
Abhijeet Satwekar Anubhab Panda Phani Nandula Sriharsha Sripada Ramachandiran Govindaraj Mara Rossi 《Biotechnology and bioengineering》2023,120(7):1822-1843
Chromatographic data processing has garnered attention due to multiple Food and Drug Administration 483 citations and warning letters, highlighting the need for a robust technological solution. The healthcare industry has the potential to greatly benefit from the adoption of digital technologies, but the process of implementing these technologies can be slow and complex. This article presents a “Digital by Design” managerial approach, adapted from pharmaceutical quality by design principles, for designing and implementing an artificial intelligence (AI)-based solution for chromatography peak integration process in the healthcare industry. We report the use of a convolutional neural network model to predict analytical variability for integrating chromatography peaks and propose a potential GxP framework for using AI in the healthcare industry that includes elements on data management, model management, and human-in-the-loop processes. The component on analytical variability prediction has a great potential to enable Industry 4.0 objectives on real-time release testing, automated quality control, and continuous manufacturing. 相似文献
396.
Hubert Gassner Josef Wanzenbck Daniela Zick Gerhard Tischler Barbara Pamminger‐Lahnsteiner 《International Review of Hydrobiology》2005,90(4):422-432
Based on the reconstructed native fish communities all natural Austrian lakes >50 ha (n = 43) were classified into four groups using cluster analysis methods. Sentinel species (i.e. species with highest discriminating value for lake types and characteristic for a specific lake group) and type specific fish species (accompanying species with additional value for characterising lake groups) were defined by a newly developed index and by similarity analysis. The first group included 16 lakes of high altitude, small surface area and low fish species number with arctic char as a sentinel species. The second group (n = 10) was characterized by intermediate altitude, large surface area and high maximum water depth with the minnow as sentinel species. The third group contained 14 lakes with low maximum water depths and a long retention time. For this group the bleak was found as a sentinel species. The lakes of the eastern part of Austria represented the last group (n = 3) and were characterized by low altitude and very shallow water depth with pike‐perch as a sentinel species. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
397.
Pelat T Bedouelle H Rees AR Crennell SJ Lefranc MP Thullier P 《Journal of molecular biology》2008,384(5):1400-1407
Fab 35PA83 is an antibody fragment of non-human primate origin that neutralizes the anthrax lethal toxin. Human antibodies are usually preferred when clinical use is envisioned, even though their framework regions (FR) may carry mutations introduced during affinity maturation. These hypermutations can be immunogenic and therefore FR that are encoded by human germline genes, encountered in IgMs and thus part of the “self” proteins, are preferable. Accordingly, the proportion of FR residues in 35PA83 that were encoded by human V and J germline genes, i.e. the germinality index (GI) of 35PA83, was increased in a multistep cumulative approach. In a first step, the FR1 and FR4 residues of 35PA83 were changed simultaneously into their counterparts coded by 35PA83's closest human germline genes, without prior modelling. The resulting derivative of 35PA83 had the same affinity as its parental Fab. In a second step, the 3D structures of this first 35PA83 derivative, carrying the same type of residue changes but in the FR2 and FR3 regions, were modelled in silico from sequences. Some of the changes in FR2 or FR3 modified the predicted peptide backbone. The changes that did not seem to alter the structure were introduced simultaneously in the Fab by an in vitro method and resulted in a loss of reactivity, which could however be fully restored by a single point mutation. The final 35PA83 derivative had a GI higher than that of a fully human Fab, which had neutralization properties similar to 35PA83 and which was used as a benchmark in this study. 相似文献
398.
Life-history strategies in freshwater macroinvertebrates 总被引:1,自引:0,他引:1
- 1 Explaining spatial and temporal differences in species assemblages is a central aim of ecology. It requires a sound understanding of the causal mechanisms underlying the relationship of species with their environment. A species trait is widely acknowledged to be the key that links pattern and process, although the enormous variety of traits hampers generalization about which combination of traits are adaptive in a particular environment.
- 2 In three steps, we used species traits to match species and environment, and chose lentic freshwater ecosystems to illustrate our approach. We first identified key environmental factors and selected the species traits that enable the organism to deal with them. Secondly, we investigated how investments in these traits are related (e.g. through trade‐offs). Thirdly, we outlined 13 life‐history strategies, based on biological species traits, their interrelations known from life‐history theory and their functional implications.
- 3 Species traits and environmental conditions are connected through life‐history strategies, with different strategies representing different solutions to particular ecological problems. In addition, strategies may present an integrated response to the environment as they are based on many different traits and their interrelationships. The presence and abundance of (species exhibiting) different life‐history strategies in a location may therefore give direct information about how a particular environment is experienced by the species present.
- 4 Life‐history strategies can be used to (i) explain differences in species assemblages either between locations or in different periods; (ii) compare waterbodies separated by large geographical distances, which may comprise different regional species pools or span species distribution areas and (iii) reduce often very complex, biodiverse assemblages into a few meaningful, easily interpretable relationships.
399.
A new conotoxin, ca16a, containing 8 cysteine residues was purified, sequenced, and cloned from a worm-hunting snail, Conus caracteristicus. This conotoxin is an extremely hydrophilic peptide comprising 34 residues, with 4 acidic and 4 basic residues. It is rich in polar Gly, Ser, and Thr residues and includes a hydroxylated Pro residue. The cysteine arrangement pattern of ca16a (-C-C-CC-C-CC-C-, designated as framework #16) is distinct from that of other known conotoxins. Furthermore, the signal peptide sequence of this conotoxin does not share any homology with those of other conotoxins. Leu residues account for almost 50% of its 20-residue signal peptide. The unique cysteine framework and signal peptide sequence of ca16a suggest that it belongs to a new conotoxin superfamily. 相似文献
400.