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681.
Jane Herbert 《Biodiversity and Conservation》2006,15(4):1459-1466
The monotypic genus Canacomyrica Guillaumin is a small tree endemic to the rare remaining fragments of primary forest growing on ultramafic geology in New
Caledonia. In the rich flora of this island it is one of many endemics to be threatened by habitat loss due to a variety of
factors, most significantly open-cast mining for nickel. Using field observations and data from herbarium specimens the extent
of occurrence of Canacomyrica monticola is established to be approximately 1420 km2. Within this area the distribution of C. monticola is very fragmented and limited to just 11 known localities. Six localities are outside protected areas; two of these may
be imminently threatened by mining activity and another may be threatened by bush fires. It is recommended that the IUCN Red
List status of Endangered (EN B1ab (i,ii,iv,v)) is assigned to this species. 相似文献
682.
Mapping the proteome of poplar and application to the discovery of drought-stress responsive proteins 总被引:7,自引:0,他引:7
683.
In this study, the importance of different domains of the fibrinogen molecule in the binding and assembly of a surface plasminogen (plgn) activator has been analyzed. This was achieved using SELDI technology that enabled dissociation of bound fragments from intact bacteria and accurate distinction between fibrinogen fragments based on their molecular mass. These studies indicate that Streptococcus pyogenes binds directly to human fibrinogen fragment D but not fragment E. The predominant surface proteins binding to fragment D were associated with the mrp gene product. Surface-associated fibrinogen fragment D was capable of anchoring a functional surface plgn activator complex. Taken together, these data indicated that fragment D of fibrinogen is necessary and sufficient to anchor a plgn activator complex on the surface of Streptococcus pyogenes. 相似文献
684.
James G Rohrbough Linda Breci Nirav Merchant Susan Miller Paul A Haynes 《Journal of biomolecular techniques》2006,17(5):327-332
Data produced from the MudPIT analysis of yeast (S. cerevisiae) and rice (O. sativa) were used to develop a technique to validate single-peptide protein identifications using complementary database search algorithms. This results in a considerable reduction of overall false-positive rates for protein identifications; the overall false discovery rates in yeast are reduced from near 25% to less than 1%, and the false discovery rate of yeast single-peptide protein identifications becomes negligible. This technique can be employed by laboratories utilizing a SEQUEST-based proteomic analysis platform, incorporating the XTandem algorithm as a complementary tool for verification of single-peptide protein identifications. We have achieved this using open-source software, including several data-manipulation software tools developed in our laboratory, which are freely available to download. 相似文献
685.
686.
The leaves of Caladium steudneriifolium (Araceae) of the understorey of a submontane rainforest in the Podocarpus National Park (South East Ecuador, 1,060 m a.s.l.)
are plain green or patterned with whitish variegation. Of the 3,413 individual leaves randomly chosen and examined in April
2003, two-thirds were plain green, whereas one third were variegated (i.e., whitish due to absence of chloroplasts). Leaves
of both morphs are frequently attacked by mining moth caterpillars. Our BLAST analysis based on Cytochrome-c-Oxidase-subunit-1 sequences suggests that the moth is possibly a member of the Pyraloidea or another microlepidopteran group.
It was observed that the variegated leaf zones strongly resemble recent damages caused by mining larvae and therefore may
mimic an attack by moth larvae. Infestation was significantly 4–12 times higher for green leaves than for variegated leaves.
To test the hypothesis that variegation can be interpreted as mimicry to deter ovipositing moths, we first ruled out the possibility
that variegation is a function of canopy density (i.e., that the moths might be attracted or deterred by factors unrelated
to the plant). Then plain green leaves were artificially variegated and the number of mining larvae counted after 3 months.
The results on infestation rate (7.88% of green leaves, 1.61% of the variegated leaves, 0.41% of white manipulated leaves
and 9.12% of uncoloured manipulated leaves) suggest that ovipositing moths are deterred by the miner-infestation mimicry.
Thus, variegation might be beneficial for the plants despite the implicated loss of photosynthetically active surface. 相似文献
687.
Sudheer Pamidiamarri DV Pandya N Reddy MP Radhakrishnan T 《Molecular biology reports》2009,36(5):901-907
Genus Jatropha with 172 species having significant economic importance belongs to the family Euphorbiaceae. There are no reports on molecular
characterization and phylogenetic relationship among the species of Jatropha. Hence, the present study was undertaken to assess the extent of genetic variability that exist and also to establish phylogenetic
relationship among Jatropha curcas, J. glandulifera, J. gossypifolia, J. integerrima, J. multifida, J. podagrica and J. tanjorensis using RAPD and AFLP. The percentage of loci that are polymorphic among the species studied was found to be 97.74% by RAPD
and 97.25% by AFLP. The mean percentage of polymorphism (PP) was found to be 68.48 by RAPD and 71.33 by AFLP. The phylogram
generated with RAPD and AFLP data showed maximum similarity. With the generated data maximum relatedness was found between
J. curcas and J. integerrima this may be the reason for the success of inter hybrid crosses between these two species. Neither RAPD nor AFLP data generated
in this study supports the view of J. tanjorensis, a natural interspecific hybrid between J. curcas and J. gossypifolia. The present study concludes that both RAPD and AFLP techniques are comparable in divergence studies of Jatropha species. The markers generated by RAPD and AFLP can be employed efficiently for interspecific hybrids identification, marker
assisted selection and genetic resource management. 相似文献
688.
689.
We have utilized Amplified Fragment Length Polymorphisms (AFLP) in conjunction with chloroplast DNA (cpDNA) sequence data to study the genetic diversity in 53 accessions of Dioscorea dumetorum from six countries in West and Central Africa. Our results provide a comparison of the two marker systems with regards to their applicability to differentiate intraspecific genotypes and the grouping of the accessions based on localities of collection. A total of 1052 AFLP fragments (of which 94.1% were polymorphic) produced from twelve primer combinations indicate a relatively high level of polymorphism among the accessions. Three major genetic groups that do not strictly follow a geographic distribution pattern were identified using Neighbour-joining and the principal coordinate (PCo) analyses. Accessions from Togo showed higher numbers of private fragments and the highest percentage polymorphism (59.4%). The detection of highest genetic diversity in accessions from Nigeria and Togo and their relationship to other accessions suggest that these countries are the centre of origin and diversity of D. dumetorum. The moderately high genetic diversity (average of 61%) is suggesting great influence on the D. dumetorum germplasms through exchange and transfer of cultivars among local farmers in the sub-region. In contrast, DNA sequence data from the psbA-trnH and the rpoB-trnC chloroplast regions revealed no variation among accessions from the different localities and clearly differentiated by AFLP patterns. The results demonstrate the usefulness of the AFLP marker in generating high polymorphism in the D. dumetorum accessions from West and Central Africa and hence may be used for agronomic purposes. 相似文献
690.
为探讨矿区优势植物粽叶芦(Thysanolaena latifolia)、类芦(Neyraudia reynaudian)和芒草(Miscanthus sinensis)的抗重金属污染能力及生态恢复潜力,对生长在铅镉污染土壤中3种植物的生理指标和重金属含量进行了测定.结果表明,同一铅、镉污染水平下3种植物的过氧化物酶活... 相似文献