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161.
Identification of cold-inducible downstream genes of the Arabidopsis DREB1A/CBF3 transcriptional factor using two microarray systems 总被引:20,自引:0,他引:20
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Oku Y Ohtaki A Kamitori S Nakamura N Yohda M Ohno H Kawarabayasi Y 《Journal of inorganic biochemistry》2004,98(7):1194-1199
Cytochrome P450 from thermoacidophilic crenarchaeon, Sulfolobus tokodaii strain 7 (P450st) has been expressed in Escherichia coli and purified at high homogeneity. P450st was crystallized in an orthorhombic system with the space group P2(1)2(1)2(1) and cell dimensions of a=53.6 A, b=55.1 A, and c=130.9 A, and the structure was determined at a 3.0 A resolution. The final R-factor was 0.194 (Rfree=0.235). Structural comparison with cytochrome P450 from S. solfataricus (CYP119) suggests that the region composed of the F to G helices and the Cl- binding site is responsible for the affinity for a ligand coordinating heme iron. Direct electrochemistry of P450st in a didodecyldimethylammonium bromide (DDAB) film on a plastic formed carbon (PFC) electrode has also been demonstrated. A quasi-reversible redox response has been observed even at elevated temperatures of up to 80 degrees C. 相似文献
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Jose B Oniki Y Kato T Nishino N Sumida Y Yoshida M 《Bioorganic & medicinal chemistry letters》2004,14(21):5343-5346
Cyclic tetrapeptides containing trifluoromethyl and pentafluoroethyl ketone as zinc binding functional group were synthesized as potent HDAC inhibitors. Evaluation by human HDAC inhibition assay and p21 promoter assay showed that these inhibitors are promising anticancer agents. 相似文献
167.
Yusuke?YamanoueEmail author Masaki?Miya Keiichi?Matsuura Masaya?Katoh Harumi?Sakai Mutsumi?Nishida 《Ichthyological Research》2004,51(3):269-273
We determined the complete nucleotide sequences of the mitochondrial genomes for the three currently recognized species of ocean sunfish: Mola mola, Masturus lanceolatus, and Ranzania laevis (Tetraodontiformes: Molidae). Each genome contained the 37 genes as found in teleosts, with the typical gene order in teleosts. Bayesian, maximum-likelihood, and maximum-parsimony analyses were conducted with the data set comprising concatenated nucleotide sequences from 36 genes (excluding the ND6 gene) of three molids and four outgroups (three tetraodontiforms plus a caproid). The resultant trees supported monophyly of the Molidae and its intrarelationships ((Mola, Masturus), Ranzania), which were congruent with previous morphology-based hypotheses. 相似文献
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Koji?HattoriEmail author Ken?Ikeuchi Yusuke?Morita Yoshinori?Takakura 《Arthritis research & therapy》2004,7(1):R38
Osteoarthritis (OA) is one of the most prevalent chronic conditions. The histological cartilage changes in OA include surface
erosion and irregularities, deep fissures, and alterations in the staining of the matrix. The reversibility of these chondral
alterations is still under debate. It is expected that clinical and basic science studies will provide the clinician with
new scientific information about the natural history and optimal treatment of OA at an early stage. However, a reliable method
for detecting microscopic changes in early OA has not yet been established. We have developed a novel system for evaluating
articular cartilage, in which the acoustic properties of the articular cartilage are measured by introducing an ultrasonic
probe into the knee joint under arthroscopy. The purpose of this study was to assess microscopic cartilage damage in OA by
using this cartilage evaluation system on collagenase-treated articular cartilage in vivo and in vitro. Ultrasonic echoes from articular cartilage were converted into a wavelet map by wavelet transformation. On the wavelet map,
the maximum magnitude and echo duration were selected as quantitative indices. Using these indices, the articular cartilage
was examined to elucidate the relationships of the ultrasonic analysis with biochemical, biomechanical and histological analyses.
In the in vitro study, the maximum magnitude decreased as the duration of collagenase digestion increased. Correlations were observed between
the maximum magnitude and the proteoglycan content from biochemical findings, and the maximum magnitude and the aggregate
modulus from biomechanical findings. From the histological findings, matrix staining of the surface layer to a depth of 500
μm was closely related to the maximum magnitude. In the in vivo study, the maximum magnitude decreased with increasing duration of the collagenase injection. There was a significant correlation
between the maximum magnitude and the aggregate modulus. The evaluation system therefore successfully detected microscopic
changes in degenerated cartilage with the use of collagen-induced OA. 相似文献
170.
RalA activation at nascent lamellipodia of epidermal growth factor-stimulated Cos7 cells and migrating Madin-Darby canine kidney cells
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RalA, a member of the Ras-family GTPases, regulates various cellular functions such as filopodia formation, endocytosis, and exocytosis. On epidermal growth factor (EGF) stimulation, activated Ras recruits guanine nucleotide exchange factors (GEFs) for RalA, followed by RalA activation. By using fluorescence resonance energy transfer-based probes for RalA activity, we found that the EGF-induced RalA activation in Cos7 cells was restricted at the EGF-induced nascent lamellipodia, whereas under a similar condition both Ras activation and Ras-dependent translocation of Ral GEFs occurred more diffusely at the plasma membrane. This EGF-induced RalA activation was not observed when lamellipodial protrusion was suppressed by a dominant negative mutant of Rac1, a GTPase-activating protein for Cdc42, inhibitors of phosphatidylinositol 3-kinase, or inhibitors of actin polymerization. On the other hand, EGF-induced lamellipodial protrusion was inhibited by microinjection of the RalA-binding domains of RalBP1 and Sec5. Furthermore, we found that RalA activity was high at the lamellipodia of migrating Madin-Darby canine kidney cells and that the migration of Madin-Darby canine kidney cells was perturbed by the microinjection of RalBP1-RalA-binding domain. Thus, RalA activation is required for the induction of lamellipodia, and conversely, lamellipodial protrusion seems to be required for the RalA activation, suggesting the presence of a positive feedback loop between RalA activation and lamellipodial protrusion. Our observation also demonstrates that the spatial regulation of RalA is conducted by a mechanism distinct from the temporal regulation conducted by Ras-dependent plasma membrane recruitment of Ral guanine nucleotide exchange factors. 相似文献