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861.
H Zealley E Edmond J M Inglis W M Shepherd D T Langford 《Journal of biological standardization》1986,14(3):213-216
The immunogenicity and clinical reactivity of rubella vaccine derived from WI-38 or MRC5 human diploid cells was compared in 125 seronegative adolescent females. Seroconversion rates, assessed by single radial haemolysis testing of paired pre- and post-vaccination samples exceeded 98% (56/57 and 68/68 vaccinees, respectively) for both vaccines. Quantitative assessment of rubella-specific antibodies in 53 post-vaccination sera by an ELISA technique also failed to reveal any difference in immunogenicity between the vaccines. Assessable calendar records documenting the occurrence of local and systemic signs and symptoms in the four weeks following vaccination were returned by 106 subjects. No important statistically significant difference in parameters of clinical reactivity between the vaccine groups was observed although the incidence of pain at the injection site was found to be significantly higher for vaccinees receiving WI-38 derived vaccine. 相似文献
862.
A rapid classification protocol for the CATH Domain Database to support structural genomics 总被引:1,自引:0,他引:1
Pearl FM Martin N Bray JE Buchan DW Harrison AP Lee D Reeves GA Shepherd AJ Sillitoe I Todd AE Thornton JM Orengo CA 《Nucleic acids research》2001,29(1):223-227
In order to support the structural genomic initiatives, both by rapidly classifying newly determined structures and by suggesting suitable targets for structure determination, we have recently developed several new protocols for classifying structures in the CATH domain database (http://www.biochem.ucl.ac.uk/bsm/cath). These aim to increase the speed of classification of new structures using fast algorithms for structure comparison (GRATH) and to improve the sensitivity in recognising distant structural relatives by incorporating sequence information from relatives in the genomes (DomainFinder). In order to ensure the integrity of the database given the expected increase in data, the CATH Protein Family Database (CATH-PFDB), which currently includes 25,320 structural domains and a further 160,000 sequence relatives has now been installed in a relational ORACLE database. This was essential for developing more rigorous validation procedures and for allowing efficient querying of the database, particularly for genome analysis. The associated Dictionary of Homologous Superfamilies [Bray,J.E., Todd,A.E., Pearl,F.M.G., Thornton,J.M. and Orengo,C.A. (2000) Protein Eng., 13, 153-165], which provides multiple structural alignments and functional information to assist in assigning new relatives, has also been expanded recently and now includes information for 903 homologous superfamilies. In order to improve coverage of known structures, preliminary classification levels are now provided for new structures at interim stages in the classification protocol. Since a large proportion of new structures can be rapidly classified using profile-based sequence analysis [e.g. PSI-BLAST: Altschul,S.F., Madden,T.L., Schaffer,A.A., Zhang,J., Zhang,Z., Miller,W. and Lipman,D.J. (1997) Nucleic Acids Res., 25, 3389-3402], this provides preliminary classification for easily recognisable homologues, which in the latest release of CATH (version 1.7) represented nearly three-quarters of the non-identical structures. 相似文献
863.
ABSTRACT: BACKGROUND: Increasingly biological text mining research is focusing on the extraction of complex relationships relevant to the construction and curation of biological networks and pathways. However, one important category of pathway - metabolic pathways - has been largely neglected. Here we present a relatively simple method for extracting metabolic reaction information from free text that scores different permutations of assigned entities (enzymes and metabolites) within a given sentence based on the presence and location of stemmed keywords. This method extends an approach that has proved effective in the context of the extraction of protein-protein interactions. RESULTS: When evaluated on a set of manually-curated metabolic pathways using standard performance criteria, our method performs surprisingly well. Precision and recall rates are comparable to those previously achieved for the well-known protein-protein interaction extraction task. CONCLUSIONS: We conclude that automated metabolic pathway construction is more tractable than has often been assumed, and that (as in the case of protein-protein interaction extraction) relatively simple text-mining approaches can prove surprisingly effective. It is hoped that these results will provide an impetus to further research and act as a useful benchmark for judging the performance of more sophisticated methods that are yet to be developed. 相似文献
864.
865.
Gene flow by pollen dispersal from forestry plantations containing introduced species, provenances or selected elite breeding
material may impact on local native forest by changing the genetic diversity, introducing new genes or gene combinations,
or causing the extinction of rare genotypes in adjacent native forest areas. Patterns of pollen flow can be used to assess
the risk of genetic pollution of native forest areas from nearby plantations. Pollen flow in an artificial population of Eucalyptus grandis was estimated using molecular markers and paternity analysis. Microsatellite genotyping was used to identify pollen parents
of progeny arrays from six mother trees. Of 329 progeny analysed, 178 (54%) were assigned to pollen parents within the population.
Pollen parents located within the population were between 0–192 m from the respective mother trees, with an average pollination
distance of 57.96 m. Pollination of mother trees was outcrossed, not by nearest neighbours, and displayed a preference for
inter-provenance matings within the population. Progeny that could not be assigned pollen parents within the population (46%)
were assumed to have resulted from pollen immigration from external sources. These pollen flow parameters provide useful information
about the dynamics of pollen movement within E. grandis populations and may be used in risk assessment of gene flow from plantations to adjacent areas of native forest. 相似文献
866.
J P Shepherd 《BMJ (Clinical research ed.)》1993,307(6908):817-818
867.
868.
869.
John G. Shepherd 《Mathematical biosciences》1982,59(1):77-93
A form for the growth term in the differential equation for biomass change with time is proposed, which is based on a versatile new family of stock-recruitment curves. The resultant yield curves of a general production model are investigated. The form of the curves is more variable than is usual in such models, but depends systematically on the values adopted for biologically well-defined parameters such as natural mortality and natural rate of increase. The consequences for management are explored by examining the magnitude of the maximum sustainable yield (MSY) and suitable values for the yield?biomass ratio.It is concluded that the MSY is of the order of but usually somewhat less than 0.5 MB0, although variation by a factor of three either way is possible. MSY is usually attained at a yield?biomass ratio no more than a few times M (the natural mortality), and at biomasses less than half the pristine biomass (B0). However, exploitation of stocks having domed stock-recruitment curves at MSY is dangerous, because the ability of the population to recover from perturbations is impaired. This is associated with an increase in the return time for the population. 相似文献
870.
A strain of Monascus was grown in submerged, shaken culture using a glucose-salts mediumn. The formation of ascospores was studied by microscopic examination of samples taken at regular intervals for 6 days. All the stages of sexual reproduction previously described for Monascus were observed. The unusual feature of the strain studied was that it produced sexual structures and cliestothecia of greatly varying sizes. 相似文献