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81.
Achim Meyer Bernhard Lieb 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2010,155(2):171-177
Three major classes of respiratory proteins are known, hemoglobin, molluscan and arthropod hemocyanin, and hemerythrin (Hr). Similar to hemoglobin, respiratory Hr is packed into erythrocytes floating in the coelomic fluid and is only known from sipunculids, brachiopods, and priapulids. Owing to this scattered distribution, the presence of Hr is generally assumed to be the plesiomorphic condition without phylogenetic importance. By sequencing 2000 Expressed Sequence Tags (ESTs) from Sipunculus nudus, we found 75 Hr-coding ESTs assembled to 20 cDNA contigs classified as four distinct Hr isoforms: three polymeric Hrs (subunit A, A', and B) and the monomeric myo-hemerythrin (myoHr). Phylogenetic analyses revealed a clade of annelid and sipunculan monomeric Hrs, distinct from polymeric Hrs. Monomeric Hrs from annelids and sipunculids can be clustered together using Maximum Likelihood tree-building and network analyses, as well as applying Bayesian methods. Three distinct Hr clusters were found for S. nudus, suggesting a new monomeric Hr isoform. 相似文献
82.
Laszlo Revesz Achim Schlapbach Reiner Aichholz Janet Dawson Roland Feifel Stuart Hawtin Amanda Littlewood-Evans Guido Koch Markus Kroemer Henrik Möbitz Clemens Scheufler Juraj Velcicky Christine Huppertz 《Bioorganic & medicinal chemistry letters》2010,20(15):4719-4723
Spirocyclopropane- and spiroazetidine-substituted tetracycles 13D–E and 16A are described as orally active MK2 inhibitors. The spiroazetidine derivatives are potent MK2 inhibitors with IC50 <3 nM and inhibit the release of TNFα (IC50<0.3 μM) from hPBMCs and hsp27 phosphorylation in anisomycin stimulated THP-1 cells. The spirocyclopropane analogues are less potent against MK2 (IC50 = 0.05–0.23 μM), less potent in cells (IC50 <1.1 μM), but show good oral absorption. Compound 13E (100 mg/kg po; bid) showed oral activity in rAIA and mCIA, with significant reduction of swelling and histological score. 相似文献
83.
Karin?Born Anja?Manns Kristina?Dzeyk Sabine?Lutz-Wahl Daniel?Gau Lutz?FischerEmail author 《Biotechnology letters》2010,32(2):249-253
Ultrasonic resonator technology (URT) was compared with the well established UV–Vis/ninhydrin assay to estimate protease activities
in defined buffer systems. Hydrolysis of casein was measured using subtilisin, trypsin, halophilic protease from Haloferax mediterranei and Bacillus lentus alkaline protease. Sensitivity, reproducibility, working range as well as the limit of detection and the limit of quantification
were comparable for both methods. Salt concentrations (0.5 M NaCl) interfered with the URT method. The quantification of protease
activity by URT was possible when the product concentration measured by the UV–Vis/ninhydrin assay was correlated to the corresponding
ultrasonic velocity signals. 相似文献
84.
85.
Henryk Flachowsky Iris Szankowski Thilo C. Fischer Klaus Richter Andreas Peil Monika Höfer Claudia Dörschel Sylvia Schmoock Achim E. Gau Heidrun Halbwirth Magda-Viola Hanke 《Planta》2010,231(3):623-635
Transgenic apple plants (Malus × domestica cv. ‘Holsteiner Cox’) overexpressing the Leaf Colour (Lc) gene from maize (Zea mays) exhibit strongly increased production of anthocyanins and flavan-3-ols (catechins, proanthocyanidins). Greenhouse plants investigated in this study exhibit altered phenotypes with regard to growth habit and resistance traits. Lc-transgenic plants show reduced size, transversal gravitropism of lateral shoots, reduced trichome development, and frequently reduced shoot diameter and abnormal leaf development with fused leaves. Such phenotypes seem to be in accordance with a direct or an indirect effect on polar-auxin-transport in the transgenic plants. Furthermore, leaves often develop necrotic lesions resembling hypersensitive response lesions. In tests, higher resistance against fire blight (caused by the bacterium Erwinia amylovora) and against scab (caused by the fungus Venturia inaequalis) is observed. These phenotypes are discussed with respect to the underlying altered physiology of the Lc-transgenic plants. The results are expected to be considered in apple breeding strategies. 相似文献
86.
Hyvönen R Agren GI Linder S Persson T Cotrufo MF Ekblad A Freeman M Grelle A Janssens IA Jarvis PG Kellomäki S Lindroth A Loustau D Lundmark T Norby RJ Oren R Pilegaard K Ryan MG Sigurdsson BD Strömgren M van Oijen M Wallin G 《The New phytologist》2007,173(3):463-480
Temperate and boreal forest ecosystems contain a large part of the carbon stored on land, in the form of both biomass and soil organic matter. Increasing atmospheric [CO2], increasing temperature, elevated nitrogen deposition and intensified management will change this C store. Well documented single-factor responses of net primary production are: higher photosynthetic rate (the main [CO2] response); increasing length of growing season (the main temperature response); and higher leaf-area index (the main N deposition and partly [CO2] response). Soil organic matter will increase with increasing litter input, although priming may decrease the soil C stock initially, but litter quality effects should be minimal (response to [CO2], N deposition, and temperature); will decrease because of increasing temperature; and will increase because of retardation of decomposition with N deposition, although the rate of decomposition of high-quality litter can be increased and that of low-quality litter decreased. Single-factor responses can be misleading because of interactions between factors, in particular those between N and other factors, and indirect effects such as increased N availability from temperature-induced decomposition. In the long term the strength of feedbacks, for example the increasing demand for N from increased growth, will dominate over short-term responses to single factors. However, management has considerable potential for controlling the C store. 相似文献
87.
A plant lectin was isolated from barley (Hordeum vulgare) coleoptiles using acidic extraction and different chromatographic methods. Sequencing of more than 50% of the protein sequence
by Edman degradation confirmed a full-length cDNA clone. The subsequently identified open reading frame encodes for a 15 kDa
protein which could be found in the soluble fraction of barley coleoptiles. This protein exhibited specificity towards mannose
sugar and is therefore, accordingly named as Horcolin (Hordeum vulgare coleoptile lectin). Database searches performed with
the Horcolin protein sequence revealed a sequence and structure homology to the lectin family of jacalin-related lectins.
Together with its affinity towards mannose, Horcolin is now identified as a new member of the mannose specific subgroup of
jacalin-related lectins in monocot species. Horcolin shares a high amino acid homology to the highly light-inducible protein
HL#2 and, in addition to two methyl jasmonic acid-inducible proteins of 32.6 and 32.7 kDa where the jasmonic acid-inducible
proteins are examples of bitopic chimerolectins containing a dirigent and jacalin-related domain. Immunoblot analysis with
a cross-reactive anti-HL#2 antibody in combination with Northern blot analysis of the Horcolin cDNA revealed tissue specific
expression of Horcolin in the coleoptiles. The function of Horcolin is discussed in the context of its particular expression
in coleoptiles and is then compared to other lectins, which apparently share a related response to biotic or abiotic stress
factors. 相似文献
88.
Tassi E Walter S Aigner A Cabal-Manzano RH Ray R Reier PJ Wellstein A 《American journal of physiology. Regulatory, integrative and comparative physiology》2007,293(2):R775-R783
The fibroblast growth factor binding protein (FGF-BP; GenBank accession no. NP_005121) is a secreted protein that mobilizes FGFs from the extracellular matrix, protects them from degradation, and enhances their biological activity. Several previous studies reported that FGF-BP is an early response gene upregulated during tissue repair processes including wound healing and atherogenesis. In this study we analyzed whether FGF-BP expression was impacted by spinal cord injury and could have an effect on neuronal cell viability. Immunohistochemical and in situ hybridization studies revealed a dramatic upregulation of FGF-BP protein and mRNA levels following unilateral hemisection and contusion injury of adult rat spinal cord. In spinal cord sections of laminectomized rats, increased FGF-BP expression was observed in the fibers and cell bodies ipsilateral to the lesion site but was absent in the uninjured spinal cord tissue contralateral to the lesion. Increased expression of FGF-BP was observed at all postinjury time points, examined with peak levels occurring at day 4, a time when injury-induced increased levels of FGF2 have also been reported to be maximal. Moreover, using PC12 cells as a neuronal model, we observed that exogenous FGF-BP increased the capacity of FGF2 to stimulate neurite outgrowth and to increase cell survival. At the molecular level, FGF-BP enhanced FGF2-induced protein tyrosine phosphorylation and AKT/PKB activation. Collectively, these results suggest that FGF-BP is an early response gene after spinal cord injury and that its upregulation in regenerating spinal cord tissue may provide a molecular mechanism for enhancing the initial FGF2-mediated neurotrophic effects occurring after such tissue damage. 相似文献
89.
Kaiser A Hammels I Gottwald A Nassar M Zaghloul MS Motaal BA Hauber J Hoerauf A 《Bioorganic & medicinal chemistry》2007,15(18):6200-6207
90.
Hausdorf B Helmkampf M Meyer A Witek A Herlyn H Bruchhaus I Hankeln T Struck TH Lieb B 《Molecular biology and evolution》2007,24(12):2723-2729
Phylogenetic analyses based on 79 ribosomal proteins of 38 metazoans, partly derived from 6 new expressed sequence tag projects for Ectoprocta, Entoprocta, Sipuncula, Annelida, and Acanthocephala, indicate the monophyly of Bryozoa comprising Ectoprocta and Entoprocta, 2 taxa that have been separated for more than a century based on seemingly profound morphological differences. Our results also show that bryozoans are more closely related to Neotrochozoa, including molluscs and annelids, than to Syndermata, the latter comprising Rotifera and Acanthocephala. Furthermore, we find evidence for the position of Sipuncula within Annelida. These findings suggest that classical developmental and morphological key characters such as cleavage pattern, coelomic cavities, gut architecture, and body segmentation are subject to greater evolutionary plasticity than traditionally assumed. 相似文献