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81.
M. Yu. Kordyukova O. V. Zatsepina M. A. Polzikov 《Applied Biochemistry and Microbiology》2011,47(2):123-127
cDNA of human gene Surf-6 (hSutf-6) was amplified and cloned into vector pGEX-2T for the expression in the bacterial system of protein hSURF-6 translationally
fused to glutathione-S-transferase. The resulting vector is named as pGEX-2T-GST-hSurf-6. Superproducer of chimeric protein
GST-hSURF-6 was obtained on the basis of Escherichia coli strain BL21-CodonPlus(DE3)-RIL. Its purification was performed by the affinity chromatography on L-glatathione-sepharose.
The proportion of recombinant protein GST-hSURF-6 in the optimized conditions was not less than 15% of the total bacterial
protein, and up to 7 mg of the protein was isolated from 1 liter of culture of the producer strain. The final fraction of
eluate contained approximately 80% of GST-hSURF-6. The amount and the purity of the isolated protein were sufficient to immunize
animals and obtain antibodies. Protein GST-hSURF-6 can also be used as an affinity ligand for revealing protein partners of
hSURF-6 in human cells. 相似文献
82.
83.
V. A. Dubrovskii B. A. Dvorkin I. Yu. Yanina V. V. Tuchin 《Cell and Tissue Biology》2011,5(5):520-529
The effect of a change in the optical properties of human adipose tissue cells in vitro after photodynamic action was studied
experimentally. The study of kinetics of this process was carried out based on the digital microscopy of thin layers of tissue.
The statistical computer processing of the obtained microimages has allowed one to quantitatively estimate the kinetics of
the photodynamic after effects on the biotissue. The optical interpretation of images indicates that the observed phenomenon
corresponds to the partial lysis of the adipose tissue cells without their complete destruction. 相似文献
84.
85.
In experiments with mono- and polycultures the hypothesis that small-size cladoceran species (Diaphanosoma brachyurum Lievin and Ceriodaphnia reticulata Jurine) are more successful at higher temperatures whereas large-size species (Daphnia magna Straus and Simocephalus vetulus O.F. Müller) under low temperatures was tested. The biomass of Simocephalus vetulus exceeded the biomass of the other species both in mono- and polycultures. An increase of temperature from 18 up to 25°C led
to reduction of the biomass of all species. The largest species, D. magna, responded to higher temperature by increased mortality. We assume that the reduction of the biomass of the large species
allowed the small C. reticulata to develop successfully in mixed cultures at higher temperature; however it was completely eliminated at lower temperature.
Apparently, the survival strategy of large cladocerans involves delayed juvenile development at lower temperatures. However,
at higher temperatures, juvenile development of large species accelerates, and their mortality increases. Individual strategies
of the studied species to survive at different temperatures are analyzed. On the whole the increase of temperature can result
in decrease of the biomass of cladocerans and prevailence of small-size species over large-size ones. 相似文献
86.
Yan-yiu Yu Chelsea Bahney Diane Hu Ralph S. Marcucio Theodore Miclau III 《Journal of visualized experiments : JoVE》2012,(62)
Assessing modes of skeletal repair is essential for developing therapies to be used clinically to treat fractures. Mechanical stability plays a large role in healing of bone injuries. In the worst-case scenario mechanical instability can lead to delayed or non-union in humans. However, motion can also stimulate the healing process. In fractures that have motion cartilage forms to stabilize the fracture bone ends, and this cartilage is gradually replaced by bone through recapitulation of the developmental process of endochondral ossification. In contrast, if a bone fracture is rigidly stabilized bone forms directly via intramembranous ossification. Clinically, both endochondral and intramembranous ossification occur simultaneously. To effectively replicate this process investigators insert a pin into the medullary canal of the fractured bone as described by Bonnarens4. This experimental method provides excellent lateral stability while allowing rotational instability to persist. However, our understanding of the mechanisms that regulate these two distinct processes can also be enhanced by experimentally isolating each of these processes. We have developed a stabilization protocol that provides rotational and lateral stabilization. In this model, intramembranous ossification is the only mode of healing that is observed, and healing parameters can be compared among different strains of genetically modified mice 5-7, after application of bioactive molecules 8,9, after altering physiological parameters of healing 10, after modifying the amount or time of stabilization 11, after distraction osteogenesis 12, after creation of a non-union 13, or after creation of a critical sized defect. Here, we illustrate how to apply the modified Ilizarov fixators for studying tibial fracture healing and distraction osteogenesis in mice. 相似文献
87.
Immunocytochemical staining has been widely used for localizing various hormonal antigens, protein markers and putative neurotransmitters in tissues. Immunostained sections can be examined light microscopically and specific areas selected for electron microscopic study. 相似文献
88.
Hsi-Feng Tu Chung-Ji Liu Che-Lun Chang Pei-Wen Wang Shou-Yen Kao Cheng-Chieh Yang En-Hao Yu Shu-Chun Lin Kuo-Wei Chang 《PloS one》2012,7(12)
MicroRNAs (miRNAs) play important roles in modulating the neoplastic process of cancers including head and neck squamous cell carcinoma (HNSCC). A genetic polymorphism (rs2292832, C>T) has been recently identified in the precursor of miR-149; nevertheless its clinicopathological implications remain obscure. In this study, we showed that miR-149 is down-regulated in HNSCC compared to normal mucosa and this is associated with a poorer patient survival. In addition, HNSCC patients with the T/T genotype have more advanced tumors and a worse prognosis. Multivariate analysis indicated that patients carried the T/T genotype have a 2.81-fold (95% CI: 1.58–4.97) increased risk of nodal metastasis and 1.66-fold (95% CI: 1.05–2.60) increased risk of mortality compared to other groups. T/T genotype also predicted the worse prognosis of buccal mucosa carcinoma subset of HNSCC. In vitro analysis indicated that exogenous miR-149 expression reduces the migration of HNSCC cells. Moreover, HNSCC cell subclones carrying the pri-mir-149 sequence containing the T variant show a low processing efficacy when converting the pre-mir-149 to mature miR-149. These findings suggest that miR-149 suppresses tumor cell mobility, and that the pre-mir-149 polymorphism may affect the processing of miR-149, resulting in a change in the abundance of the mature form miRNA, which, in turn, modulates tumor progression and patient survival. 相似文献
89.
90.
Journal of Ichthyology - Information on stone cockscomb Alectrias alectrolophus diet in Avacha Bay (eastern Kamchatka) are presented, and seasonal, local, age, and interannual changes in the... 相似文献