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991.
Johannes Kollmann Kasper Brink‐Jensen Sally I. Frandsen Mille K. Hansen 《Restoration Ecology》2011,19(3):371-378
Invasive alien plants are a problem for conservation management, and control of these species can be combined with habitat restoration. Subsoil burial of uprooted plants is a new method of mechanical control, which might be suitable in disturbed habitats. The method was tested in Rosa rugosa (Japanese Rose), an invasive shrub in north‐western Europe with negative effects on coastal biodiversity. Two months after uprooting and burial in dunes of north‐eastern Denmark, 89% of the 58 shrubs resprouted from roots and rhizomes; on average 41 resprouts per shrub. Resprout density was twice as high at former shrub margins compared with the center; resprouts were taller and originated from more superficial soil layers at the margin than in the center. Resprouting was negatively correlated with fragment depth, and no resprouts were observed from greater than 15 cm depth. The number of resprouts increased with fragment dry mass (0.5–168.5 g). After 18 months with harrowing the species was still resprouting, flowering, and fruiting, albeit with no difference between shrub margin and center. Resprouts were taller (26 cm) and coverage was higher (0–4%) after two compared with three times harrowing, whereas no difference was found in cover of native dune species (1–5%). The results show that even small fragments of R. rugosa resprout, and that resprouting persists despite repeated harrowing. Thus, careful subsoil burial of all fragments is necessary, special attention should be paid to the shrub margin, and follow‐up treatments are needed. The effectiveness of the burial method is discussed for restoration of coastal dunes. 相似文献
992.
The heterotrimeric structure of kinesin-2 makes it a unique member of the kinesin superfamily; however, molecular details of the oligomer formation are largely unknown. Here we demonstrate that heterodimerization of the two distinct motor domains KLP11 and KLP20 of Caenorhabditis elegans kinesin-2 requires a dimerization seed of merely two heptads at the C terminus of the stalk. This heterodimeric seed is sufficient to promote dimerization along the entire length of the stalk, as shown by circular dichroism spectroscopy, Förster resonance energy transfer analysis, and electron microscopy. In addition to explaining the formation of the kinesin-2 stalk, the seed sequence identified here bears great potential for generating specific heterodimerization in other protein biochemical applications. 相似文献
993.
Kotzsch M Dorn J Doetzer K Schmalfeldt B Krol J Baretton G Kiechle M Schmitt M Magdolen V 《Biological chemistry》2011,392(11):1047-1051
High tumor tissue mRNA expression of the tumor biological factors uPAR, uPAR-del4/5, or rab31 is associated with shorter distant metastasis-free and overall survival in breast cancer patients. To evaluate whether these factors are also clinically relevant in ovarian cancer, we quantified the respective mRNA levels in primary tumor tissue of advanced ovarian cancer patients (n=103) and evaluated their association with clinicopathological parameters and patients' prognosis. mRNA expression levels of all three markers did not show any significant association with overall or progression-free survival, demonstrating that these factors have no prognostic value in advanced ovarian cancer. 相似文献
994.
Füchtbauer A Lassen LB Jensen AB Howard J Quiroga Ade S Warming S Sørensen AB Pedersen FS Füchtbauer EM 《Biological chemistry》2011,392(8-9):769-777
Septin9 (Sept9) is a member of the filament-forming septin family of structural proteins and is associated with a variety of cancers and with hereditary neuralgic amyotrophy. We have generated mice with constitutive and conditional Sept9 knockout alleles. Homozygous deletion of Sept9 results in embryonic lethality around day 10 of gestation whereas mice homozygous for the conditional allele develop normally. Here we report the consequences of homozygous loss of Sept9 in immortalized murine embryonic fibroblasts. Proliferation rate was not changed but cells without Sept9 had an altered morphology compared to normal cells, particularly under low serum stress. Abnormal, fragmented, and multiple nuclei were more frequent in cells without Sept9. Cell migration, as measured by gap-filling and filter-invasion assays, was impaired, but individual cells did not move less than wild-type cells. Sept9 knockout cells showed a reduced resistance to hypo-osmotic stress. Stress fiber and vinculin staining at focal adhesion points was less prominent. Long septin filaments stained for Sept7 disappeared. Instead, staining was found in short, often curved filaments and rings. Furthermore, Sept7 was no longer localized to the mitotic spindle. Together, these data reveal the importance of Sept9 for septin filament formation and general cell stability. 相似文献
995.
Astrocytes are glial cells, which play a significant role in a number of processes, including the brain energy metabolism. Their anatomical position between blood vessels and neurons make them an interface for effective glucose uptake from blood. After entering astrocytes, glucose can be involved in different metabolic pathways, e.g. in glycogen production. Glycogen in the brain is localized mainly in astrocytes and is an important energy source in hypoxic conditions and normal brain functioning. The portion of glucose metabolized into glycogen molecules in astrocytes is as high as 40%. It is thought that the release of gliotransmitters (such as glutamate, neuroactive peptides and ATP) into the extracellular space by regulated exocytosis supports a significant part of communication between astrocytes and neurons. On the other hand, neurotransmitter action on astrocytes has a significant role in brain energy metabolism. Therefore, understanding the astrocytes energy metabolism may help understanding neuron-astrocyte interactions. 相似文献
996.
997.
Nelson MR Howard D Jensen OE King JR Rose FR Waters SL 《Biomechanics and modeling in mechanobiology》2011,10(6):883-900
We use a proof-of-concept experiment and two mathematical models to explore growth-induced tissue buckling, as may occur in
colorectal crypt formation. Our experiment reveals how growth of a cultured epithelial monolayer on a thin flexible substrate
can cause out-of-plane substrate deflections. We describe this system theoretically using a ‘bilayer’ model in which a growing
cell layer adheres to a thin compressible elastic beam. We compare this with the ‘supported-monolayer’ model due to Edwards
and Chapman (Bull Math Biol 69:1927–1942, 2007) for an incompressible expanding beam (representing crypt epithelium), which incorporates viscoelastic tethering to underlying
stroma. We show that the bilayer model can exhibit buckling via parametric growth (in which the system passes through a sequence
of equilibrium states, parameterised by the total beam length); in this case, non-uniformities in cell growth and variations
in cell–substrate adhesion are predicted to have minimal effect on the shape of resulting buckled states. The supported-monolayer
model reveals how competition between lateral supports and stromal adhesion influences the wavelength of buckled states (in
parametric growth), and how non-equilibrium relaxation of tethering forces influences post-buckled shapes. This model also
predicts that non-uniformities in growth patterns have a much weaker influence on buckled shapes than non-uniformities in
material properties. Together, the experiment and models support the concept of patterning by growth-induced buckling and
suggest that targeted softening of a growing cell layer provides greater control in shaping tissues than non-uniform growth. 相似文献
998.
Klaus Koefoed Lucilla Steinaa Josefine Nielsen S?derberg Ida Kj?r Helle Jane Jacobsen Per-Johan Meijer John S?rensen Haurum Allan Jensen Michael Kragh Peter Sejer Andersen Mikkel Wandahl Pedersen 《MABS-AUSTIN》2011,3(6):584-595
The epidermal growth factor receptor (EGFR) is frequently dysregulated in human malignancies and a validated target for cancer therapy. Two monoclonal anti-EGFR antibodies (cetuximab and panitumumab) are approved for clinical use. However, the percentage of patients responding to treatment is low and many patients experiencing an initial response eventually relapse. Thus, the need for more efficacious treatments remains. Previous studies have reported that mixtures of antibodies targeting multiple distinct epitopes are more effective than single mAbs at inhibiting growth of human cancer cells in vitro and in vivo. The current work describes the rational approach that led to discovery and selection of a novel anti-EGFR antibody mixture Sym004, which is currently in Phase 2 clinical testing. Twenty-four selected anti-EGFR antibodies were systematically tested in dual and triple mixtures for their ability to inhibit cancer cells in vitro and tumor growth in vivo. The results show that targeting EGFR dependent cancer cells with mixtures of antibodies is superior at inhibiting their growth both in vitro and in vivo. In particular, antibody mixtures targeting non-overlapping epitopes on domain III are efficient and indeed Sym004 is composed of two monoclonal antibodies targeting this domain. The superior growth inhibitory activity of mixtures correlated with their ability to induce efficient EGFR degradation.Key words: EGFR, antibody synergy, functional screening, epitope binning, antibody combinations 相似文献
999.
Pati A Gronow S Zeytun A Lapidus A Nolan M Hammon N Deshpande S Cheng JF Tapia R Han C Goodwin L Pitluck S Liolios K Pagani I Ivanova N Mavromatis K Chen A Palaniappan K Land M Hauser L Chang YJ Jeffries CD Detter JC Brambilla E Rohde M Göker M Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Kyrpides NC Klenk HP Lucas S 《Standards in genomic sciences》2011,4(1):45-53
Bacteroides helcogenes Benno et al. 1983 is of interest because of its isolated phylogenetic location and, although it has been found in pig feces and is known to be pathogenic for pigs, occurrence of this bacterium is rare and it does not cause significant damage in intensive animal husbandry. The genome of B. helcogenes P 36-108(T) is already the fifth completed and published type strain genome from the genus Bacteroides in the family Bacteroidaceae. The 3,998,906 bp long genome with its 3,353 protein-coding and 83 RNA genes consists of one circular chromosome and is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献
1000.
Chertkov O Sikorski J Nolan M Lapidus A Lucas S Del Rio TG Tice H Cheng JF Goodwin L Pitluck S Liolios K Ivanova N Mavromatis K Mikhailova N Ovchinnikova G Pati A Chen A Palaniappan K Djao OD Land M Hauser L Chang YJ Jeffries CD Brettin T Han C Detter JC Rohde M Göker M Woyke T Bristow J Eisen JA Markowitz V Hugenholtz P Klenk HP Kyrpides NC 《Standards in genomic sciences》2011,4(1):13-22
Thermomonospora curvata Henssen 1957 is the type species of the genus Thermomonospora. This genus is of interest because members of this clade are sources of new antibiotics, enzymes, and products with pharmacological activity. In addition, members of this genus participate in the active degradation of cellulose. This is the first complete genome sequence of a member of the family Thermomonosporaceae. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 5,639,016 bp long genome with its 4,985 protein-coding and 76 RNA genes is a part of the Genomic Encyclopedia of Bacteria and Archaea project. 相似文献