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71.
Mashitoh Abd Rahman Faiqah Ramli Hamed Karimian Firouzeh Dehghan Noraziah Nordin Hapipah Mohd Ali Syam Mohan Najihah Mohd Hashim 《PloS one》2016,11(3)
Artonin E is a prenylated flavonoid isolated from the stem bark of Artocarpus elasticus Reinw.(Moraceae). This study aimed to investigate the apoptotic mechanisms induced by artonin E in a metastatic human ovarian cancer cell line SKOV-3 in vitro. MTT assay, clonogenic assay, acridine orange and propidium iodide double staining, cell cycle and annexin V analyses were performed to explore the mode of artonin E-induced cell death at different time points. DNA laddering, activation of caspases-3, -8, and -9, multi-parametric cytotoxicity-3analysis by high-content screening, measurement of reactive oxygen species generation, and Western blot were employed to study the pathways involved in the apoptosis. MTT results showed that artonin E inhibited the growth of SKOV-3 cells, with IC50 values of 6.5±0.5μg/mL after 72 h treatment, and showed less toxicity toward a normal human ovarian cell lineT1074, with IC50 value of 32.5±0.5μg/mL. Results showed that artonin E induced apoptosis and cell cycle arrest at the S phase. This compound also promoted the activation of caspases-3, -8, and -9. Further investigation into the depletion of mitochondrial membrane potential and release of cytochrome c revealed that artonin E treatment induced apoptosis via regulation of the expression of pro-survival and pro-apoptotic Bcl-2 family members. The expression levels of survivin and HSP70 proteins were also down regulated in SKOV-3 cells treated with artonin E. We propose that artonin E induced an antiproliferative effect that led to S phase cell cycle arrest and apoptosis through dysregulation of mitochondrial pathways, particularly the pro- and anti-apoptosis signaling pathways. 相似文献
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Plasmonics - Polarization reconfigurable dielectric resonator antenna (DRA) backed by plasma artificial magnetic conductor (AMC) ground plane is designed and optimized for 10-GHz applications. The... 相似文献
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Rahman Daiyan Emma Catherine Lovell Bosi Huang Muhammad Zubair Joshua Leverett Qingran Zhang Sean Lim Jonathan Horlyck Jianbo Tang Xunyu Lu Kourosh Kalantar‐Zadeh Judy N. Hart Nicholas M. Bedford Rose Amal 《Liver Transplantation》2020,10(28)
In this study, scalable, flame spray synthesis is utilized to develop defective ZnO nanomaterials for the concurrent generation of H2 and CO during electrochemical CO2 reduction reactions (CO2RR). The designed ZnO achieves an H2/CO ratio of ≈1 with a large current density (j) of 40 mA cm?2 during long‐term continuous reaction at a cell voltage of 2.6 V. Through in situ atomic pair distribution function analysis, the remarkable stability of these ZnO structures is explored, addressing the knowledge gap in understanding the dynamics of oxide catalysts during CO2RR. Through optimization of synthesis conditions, ZnO facets are modulated which are shown to affect reaction selectivity, in agreement with theoretical calculations. These findings and insights on synthetic manipulation of active sites in defective metal‐oxides can be used as guidelines to develop active catalysts for syngas production for renewable power‐to‐X to generate a range of fuels and chemicals. 相似文献
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Daniele Novarina Georges E. Janssens Koen Bokern Tim Schut Noor C. van Oerle Hinke G. Kazemier Liesbeth M. Veenhoff Michael Chang 《Aging cell》2020,19(2)
To ensure proper transmission of genetic information, cells need to preserve and faithfully replicate their genome, and failure to do so leads to genome instability, a hallmark of both cancer and aging. Defects in genes involved in guarding genome stability cause several human progeroid syndromes, and an age‐dependent accumulation of mutations has been observed in different organisms, from yeast to mammals. However, it is unclear whether the spontaneous mutation rate changes during aging and whether specific pathways are important for genome maintenance in old cells. We developed a high‐throughput replica‐pinning approach to screen for genes important to suppress the accumulation of spontaneous mutations during yeast replicative aging. We found 13 known mutation suppression genes, and 31 genes that had no previous link to spontaneous mutagenesis, and all acted independently of age. Importantly, we identified PEX19, encoding an evolutionarily conserved peroxisome biogenesis factor, as an age‐specific mutation suppression gene. While wild‐type and pex19Δ young cells have similar spontaneous mutation rates, aged cells lacking PEX19 display an elevated mutation rate. This finding suggests that functional peroxisomes may be important to preserve genome integrity specifically in old cells. 相似文献
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Rodrigues Vereena Kumar Amit Gokul Sivaraman Verma Ram S. Rahman Laiq ur Sundaresan Velusamy 《In vitro cellular & developmental biology. Plant》2020,56(4):526-537
In Vitro Cellular & Developmental Biology - Plant - An efficient in vitro propagation and synthetic seed production protocol was established for the conservation of Decalepis salicifolia (Bedd.... 相似文献
80.
Inamur Rahman Lina Fang Zhang Wei Xiaodong Zheng Lei Huang 《Preparative biochemistry & biotechnology》2020,50(6):598-606
AbstractHuman basic fibroblast growth factor (hbFGF) is involved in a wide range of biological activities that affect the growth, differentiation, and migration. Due to its wound healing effects and therapy, hbFGF has the potential as therapeutic agent. Therefore, large-scale production of biologically active recombinant hbFGF with low cost is highly desirable. However, the complex structure of hbFGF hinders its high-level expression as the soluble and functional form. In the present study, an efficient, cost-effective, and scalable method for producing recombinant hbFGF was developed. The modified collagen-like protein (Scl2-M) from Streptococcus pyogenes was used as the fusion tag for producing recombinant hbFGF for the first time. After optimization, the expression level of Scl2-M-hbFGF reached approximately 0.85?g/L in the shake flask and 7.7?g/L in a high cell-density fermenter using glycerol as a carbon source. Then, the recombinant Scl2-M-hbFGF was readily purified using one-step acid precipitation and the purified Scl2-M-hbFGF was digested with enterokinase. The digested mixture was further subject to ion-exchange chromatography, and the final high-purity (96%) hbFGF product was prepared by freeze-drying. The recovery rate of the whole purification process attained 55.0%. In addition, the biological activity of recombinant hbFGF was confirmed by using L929 and BALB/c3T3 fibroblasts. Overall, this method has the potential for large scale production of recombinant hbFGF. 相似文献