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991.
992.
Hoppen J Dietz M Warsow G Rohde R Schüller HJ 《Molecular genetics and genomics : MGG》2007,278(3):317-330
993.
Recently we reported that Catalase-1 (CAT-1) played an important role in protecting conidial viability in Neurospora crassa, and interacted with a light signal transducer, nucleoside diphosphate kinase-1 (NDK-1). To disclose the functional interaction
between CAT-1 and NDK-1 at the genetic level, we created CAT-1 and NDK-1 double mutants, cat-1;ndk-1-1 and cat-1;ndk-1-2, by crossing single mutants of cat-1
RIP
and ndk-1
P72H
previously isolated in our laboratory. The double mutant strains grew normally, but showed increased CAT-2 activity. In cat-1
RIP
, NDK activity was increased when dCDP was used as a substrate. ndk-1
P72H
, cat-1;ndk-1-1, and cat-1;ndk-1-2 were more sensitive to riboflavin than the wild type and cat-1
RIP
under strong light (100 μE m−2 s−1). The pull-down experiment suggests that His-tagged NDK-1 is bound to [32P]NADH. However, his-tagged NDK-1P72H was not bound to [32P]NADH. The double mutants showed much lower conidial viability and lost all conidial germination ability much more rapidly
than cat-1
RIP
, when they were cultured under continuous light for more than 2 weeks. These results indicate that the interaction of CAT-1
with NDK-1 plays an important role in supporting the survival of conidia under oxidative and light-induced stress including
singlet oxygen, and confirm our former conclusion that reactive oxygen species play an important role in light signal transduction
via NDK-1 at the genetic level.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
994.
995.
996.
997.
Eleven novel polymorphic microsatellite loci developed from a microsatellite enriched genomic library, are presented for the
Australian tree frog Litoria peronii. We screened 29 individuals from a single population and detected high levels of polymorphism for all 11 loci with the number
of alleles/locus ranging from 9 to 24. Values of expected and observed heterozygosities ranged from 0.789–0.955 and 0.207–1.00,
respectively. These microsatellite markers should prove useful in determining levels of genetic diversity, measuring gene
flow and migration, assigning individuals to their most likely population of origin, and in the assignment of paternity. 相似文献
998.
Naohisa Kanda Mutsuo Goto Hidehiro Kato Megan V. McPhee Luis A. Pastene 《Conservation Genetics》2007,8(4):853-864
Bryde’s whales (Balaenoptera brydei) differ from other typical baleen whale species because they are restricted to tropical and warm temperate waters in major
oceans, and frequent trans-equatorial movement has been suggested for the species. We tested this hypothesis by analyzing
genetic variation at 17 microsatellite loci (N = 508) and 299 bp of mitochondrial DNA (mtDNA) control region sequences (N = 472) in individuals obtained from the western North Pacific, South Pacific, and eastern Indian Ocean. Combined use of microsatellite
and mtDNA markers allowed us to distinguish between contemporary gene flow and ancestral polymorphism and to describe sex-specific
philopatry. A high level of genetic diversity was found within the samples. Both nuclear and mtDNA markers displayed similar
population structure, indicating a lack of sex-specific philopatry. Spatial structuring was detected using both frequency-based
population parameters and individual-based Bayesian approaches. Whales in the samples from different oceanic regions came
from genetically distinct populations with evidence of limited gene flow. We observed low mtDNA sequence divergence among
populations and a lack of concordance between geographic and phylogenetic position of mtDNA haplotypes, suggesting recent
separation of populations rather than frequent trans-equatorial and inter-oceanic movement. We conclude that current gene
flow between Bryde’s whale populations is low and that effective management actions should treat them as separate entities
to ensure continued existence of the species. 相似文献
999.
Various approaches have been developed to define conservation units for plant and animal species. In this study we combined
nuclear microsatellites (from a previous published study) and chloroplast microsatellites (assessed in the present study),
leaf and seed morphology traits and abiotic variables (climate and soil) to define evolutionary significant units (ESU) of
Santalum austrocaledonicum, a tree species growing in New Caledonia. Results for chloroplast microsatellites showed that the total population heterozygosity
was␣high, (H
cp = 0.84) but varied between islands. Differentiation was strong in the total population (F
stcp = 0.66) but also within the main island Grande Terre (F
stcp = 0.73) and within Iles Loyauté (F
stcp = 0.52), highlighting a limited gene flow between populations. These results confirmed those obtained with nuclear microsatellites.
The cluster analysis on molecular markers discriminated two main groups constituted by the populations of Grande Terre and
the populations of Iles Loyauté. A principal component analysis of leaf and seed morphology traits singled out the populations
of Iles Loyauté and the western populations of Grande Terre. Quantitative genetic analyses showed that the variation between
populations was under genetic control (broad sense heritability close to 80%). A high correlation between rainfall and morphological
traits suggested an impact of climate on this variation. The integration of these results allows to define two ESUs, one corresponding
to Grande Terre and Ile des Pins and the other the Iles Loyauté archipelago. This study stresses the need to restore some
populations of Grande Terre that are currently threatened by their small size. 相似文献
1000.
Stephen D. Petersen Tom Mason Sarah Akber Rick West Brad White Paul Wilson 《Conservation Genetics》2007,8(2):497-502
This paper outlines a novel, non-invasive procedure to obtain DNA from Mexican tarantulas (Brachypelma spp.) using exuvia. These species are important in the pet trade and species identification is important for international
wildlife law enforcement. Mitochondrial DNA sequence from the cytochrome c oxidase subunit I gene was used to investigate the relationship between various Brachypelma spp. This phylogeny was used as a framework to assign unknown specimens and spiderlings to species. The benefits to conservation,
research, and international wildlife law enforcement that are gained by the ability to accurately identify species without
the death of the specimen are explored. Our data also suggest that there is no support for the genus Brachypelmides as some authors have proposed and upholds the synonymy of Locht et al. (1999) J Arachnol 27:196–200. 相似文献