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991.
Man-Hei Cheung Aftab Amin Rentian Wu Yan Qin Lan Zou Zhiling Yu 《Cell cycle (Georgetown, Tex.)》2019,18(5):605-620
Noc3p (Nucleolar Complex-associated protein) is an essential protein in budding yeast DNA replication licensing. Noc3p mediates the loading of Cdc6p and MCM proteins onto replication origins during the M-to-G1 transition by interacting with ORC (Origin Recognition Complex) and MCM (Minichromosome Maintenance) proteins. FAD24 (Factor for Adipocyte Differentiation, clone number 24), the human homolog of Noc3p (hNOC3), was previously reported to play roles in the regulation of DNA replication and proliferation in human cells. However, the role of hNOC3 in replication licensing was unclear. Here we report that hNOC3 physically interacts with multiple human pre-replicative complex (pre-RC) proteins and associates with known replication origins throughout the cell cycle. Moreover, knockdown of hNOC3 in HeLa cells abrogates the chromatin association of other pre-RC proteins including hCDC6 and hMCM, leading to DNA replication defects and eventual apoptosis in an abortive S-phase. In comparison, specific inhibition of the ribosome biogenesis pathway by preventing pre-rRNA synthesis, does not lead to any cell cycle or DNA replication defect or apoptosis in the same timeframe as the hNOC3 knockdown experiments. Our findings strongly suggest that hNOC3 plays an essential role in pre-RC formation and the initiation of DNA replication independent of its potential role in ribosome biogenesis in human cells. 相似文献
992.
993.
Yin Hu Wei Chen Tianyu Lei Bin Zhou Yu Jiao Yichao Yan Xinchuan Du Jianwen Huang Chunyang Wu Xuepeng Wang Yang Wang Bo Chen Jun Xu Chao Wang Jie Xiong 《Liver Transplantation》2019,9(7)
Significant progress has achieved for developing lithium–sulfur (Li–S) batteries with high specific capacities and excellent cyclic stability. However, some critical issues emerge when attempts are made to raise the areal sulfur loading and increase the operation current density to meet the standards for various industrial applications. In this work, polyethylenimine‐functionalized carbon dots (PEI‐CDots) are designed and prepared for enhancing performance of the Li–S batteries with high sulfur loadings and operation under high current density situations. Strong chemical binding effects towards polysulfides and fast ion transport property are achieved in the PEI‐CDots‐modified cathodes. At a high current density of 8 mA cm?2, the PEI‐CDots‐modified Li–S battery delivers a reversible areal capacity of 3.3 mAh cm?2 with only 0.07% capacity decay per cycle over 400 cycles at 6.6 mg sulfur loading. Detailed analysis, involving electrochemical impedance spectroscopy, cyclic voltammetry, and density functional theory calculations, is done for the elucidation of the underlying enhancement mechanism by the PEI‐CDots. The strongly localized sulfur species and the promoted Li+ ion conductivity at the cathode–electrolyte interface are revealed to enable high‐performance Li–S batteries with high sulfur loading and large operational current. 相似文献
994.
Herein, a new P2‐type layered oxide is proposed as an outstanding intercalation cathode material for high energy density sodium‐ion batteries (SIBs). On the basis of the stoichiometry of sodium and transition metals, the P2‐type Na0.55[Ni0.1Fe0.1Mn0.8]O2 cathode is synthesized without impurities phase by partially substituting Ni and Fe into the Mn sites. The partial substitution results in a smoothing of the electrochemical charge/discharge profiles and thus greatly improves the battery performance. The P2‐type Na0.55[Ni0.1Fe0.1Mn0.8]O2 cathode delivers an extremely high discharge capacity of 221.5 mAh g?1 with a high average potential of ≈2.9 V (vs Na/Na+) for SIBs. In addition, the fast Na‐ion transport in the P2‐type Na0.55[Ni0.1Fe0.1Mn0.8]O2 cathode structure enables good power capability with an extremely high current density of 2400 mA g?1 (full charge/discharge in 12 min) and long‐term cycling stability with ≈80% capacity retention after 500 cycles at 600 mA g?1. A combination of electrochemical profiles, in operando synchrotron X‐ray diffraction analysis, and first‐principles calculations are used to understand the overall Na storage mechanism of P2‐type Na0.55[Ni0.1Fe0.1Mn0.8]O2. 相似文献
995.
996.
Xue Liu Yu Meng Zanpei Zhang Yihan Wang Xiaodong Geng Mingwan Li Zhi Li Dangquan Zhang 《Saudi Journal of Biological Sciences》2019,26(6):1227-1246
Cinnamomum camphora is an excellent tree species for construction of forest construction of Henan Province, China. The diverse bioactive components of nano-catalyzed pyrolyzates form cold-acclimated C. camphora branch (CCB) in North China were explored. The raw powder of CCB treated with nano-catalyst (Ag, NiO, 1/2Ag + 1/2NiO) were pyrolyzed at two temperatures (550 °C and 700 °C), respectively. The main pyrolyzates are bioactive components of bioenergy, biomedicines, food additive, spices, cosmetics and chemical, whose total relative contents at 550 °C pyrolyzates are higher than those at 700 °C pyrolyzates. There are abundant components of spices and biomedicine at 550 °C pyrolyzates, while more spices and food additive at 700 °C pyrolyzates. At 550 °C, the content of biomedicine components reaches the highest by 1/2Ag + 1/2NiO nanocatalysis, while the contents of spices and food additive components reach the highest by NiO nanocatalysis. At 700 °C, the content of bioenergy components reaches the highest by 1/2Ag + 1/2NiO nanocatalysis, and the content of cosmetics components reaches the highest by Ag nanocatalysis. The findings suggested that the branch of the cold-acclimated C. camphora have the potential to develop into valued-added products of bioenergy, biomedicine, cosmetics, spices and food additive by nanocatalysis. 相似文献
997.
H.T. Nguyen S. Kim N.H. Yu A.R. Park H. Yoon C.-H. Bae J.H. Yeo I.S. Kim J.-C. Kim 《Journal of applied microbiology》2019,126(3):894-904
998.
999.
Birong Zhang James R. Kiefer Robert A. Blake Jae H. Chang Steven Hartman Ellen Rei Ingalla Tracy Kleinheinz Vidhi Mody Michelle Nannini Daniel F. Ortwine Yingqing Ran Amy Sambrone Deepak Sampath Maia Vinogradova Yu Zhong Jerome C. Nwachukwu Kendall W. Nettles Tommy Lai Jun Liang 《Bioorganic & medicinal chemistry letters》2019,29(7):905-911
Despite tremendous progress made in the understanding of the ERα signaling pathway and the approval of many therapeutic agents, ER+?breast cancer continues to be a leading cause of cancer death in women. We set out to discover compounds with a dual mechanism of action in which they not only compete with estradiol for binding with ERα, but also can induce the degradation of the ERα protein itself. We were attracted to the constrained chromenes containing a tetracyclic benzopyranobenzoxepine scaffold, which were reported as potent selective estrogen receptor modulators (SERMs). Incorporation of a fluoromethyl azetidine side chain yielded highly potent and efficacious selective estrogen receptor degraders (SERDs), such as 16aa and surprisingly, also its enantiomeric pair 16ab. Co-crystal structures of the enantiomeric pair 16aa and 16ab in complex with ERα revealed default (mimics the A-D rings of endogenous ligand estradiol) and core-flipped binding modes, rationalizing the equivalent potency observed for these enantiomers in the ERα degradation and MCF-7 anti-proliferation assays. 相似文献