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121.
Qinghua Xie Xia Li Guanquan Wang Xuan Hou Yujun Wang Hongbo Yu Changfa Qu Shunzhong Luo Yali Cui Chuanqin Xia Ruibing Wang 《Journal of Radioanalytical and Nuclear Chemistry》2017,311(3):1697-1708
Here we reported the radiolabeling and evaluation of a novel 131I-radiolabeled quercetin for the treatment of dedifferentiated thyroid cancers. The human thyroid cancer cell lines (FTC-133, TT and DRO) experienced much higher uptake of 131I-quercetin as compared to the free 131I. And the proliferation inhibition rate of 131I-quercetin on in vitro DRO cell line was 86.87 ± 7.15%. Biodistribution and SPECT analysis demonstrated that the injected radioactivity mainly accumulated in tumors. The tumor volume in the treatment group was dramatically inhibited in comparison with the control group. 相似文献
122.
Yuhua Xue Jun Liu Hao Chen Ruigang Wang Dingqiang Li Jia Qu Liming Dai 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2012,124(48):12300-12300
123.
Jing Wu Ying Qu Kun Shi Bingyang Chu Yanpeng Jia Xue Xiao Qianjun He Zhiyong Qian 《中国化学快报》2018,29(12):1819-1823
The CPT was loaded into the HMSNs with the high loading capacity. Then the CPT@HMSNs were loaded into the PLEL thermosensitive hydrogels for local therapy to prevent the recurrence of breast cancer after the tumor was resected. 相似文献
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126.
Jiafu Wang Shaobo Qu Zhuo Xu Hua Ma Xinhua Wang Daqing Huang Yongfeng Li 《Photonics and Nanostructures》2012,10(4):540-546
We demonstrated the possibility of designing super-thin electromagnetic cloaks based on spoof surface plasmon (SSP). Using a metamaterial layer, incident waves can be coupled into SSP efficiently at the air/metamaterial interface. Due to the strong surface confinement of SSP, EM waves are squeezed into and propagate in deep sub-wavelength scales. Implementation of an 8.2 GHz cloak less than 1/50 the cloaking diameter was presented using split ring resonator (SRR). Excellent cloaking effect was verified by simulations. Rather than isolating objects from the background, such cloaks can drastically enhance the field intensity around the cloaked object. This is of particular importance in applications such as weak wave detection and near-field sensing. 相似文献
127.
Yinwu Li Jiahao Liu Dr. Xiao Huang Prof. Dr. Ling-Bo Qu Prof. Dr. Cunyuan Zhao Prof. Dr. Robert Langer Prof. Dr. Zhuofeng Ke 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(60):13785-13798
As a new type of bifunctional catalyst, the Lewis acid transition-metal (LA-TM) catalysts have been widely applied for hydrogen activation. This study presents a mechanistic framework to understand the LA-TM-catalyzed H2 activation through DFT studies. The mer(trans)-homolytic cleavage, the fac(cis)-homolytic cleavage, the synergetic heterolytic cleavage, and the dissociative heterolytic cleavage should be taken as general mechanisms for the field of LA-TM catalysis. Four typical LA-TM catalysts, the Z-type κ4-L3B-Rh complex tri(azaindolyl)borane-Rh, the X-type κ3-L2B-Co complex bis-phosphino-boryl (PBP)-Co, the η2-BC-type κ3-L2B-Pd complex diphosphine-borane (DPB)-Pd, and the Z-type κ2-LB-Pt complex (boryl)iminomethane (BIM)-Pt are selected as representative models to systematically illustrate their mechanistic features and explore the influencing factors on mechanistic variations. Our results indicate that the tri(azaindolyl)borane-Rh catalyst favors the synergetic heterolytic mechanism; the PBP-Co catalyst prefers the mer(trans)-homolytic mechanism; the DPB-Pd catalyst operates through the fac(cis)-homolytic mechanism, whereas the BIM-Pt catalyst tends to undergo the dissociative heterolytic mechanism. The mechanistic variations are determined by the coordination geometry, the LA-TM bonding nature, the electronic structure of the TM center, and the flexibility or steric effect of the LA ligands. The presented mechanistic framework should provide helpful guidelines for LA-TM catalyst design and reaction developments. 相似文献
128.
Mengmeng Ma Ying Wang Nan Gao Xinping Liu Yuhuan Sun Prof. Jinsong Ren Prof. Dr. Xiaogang Qu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(51):11852-11858
Proteolysis of amyloid-β (Aβ) is a promising approach against Alzheimer's disease. However, it is not feasible to employ natural hydrolases directly because of their cumbersome preparation and purification, poor stability, and hazardous immunogenicity. Therefore, artificial enzymes have been developed as potential alternatives to natural hydrolases. Since specific cleavage sites of Aβ are usually embedded inside the β-sheet structures that restrict access by artificial enzymes, this strongly hinders their efficiency for practical applications. Herein, we construct a NIR (near-IR) controllable artificial metalloprotease (MoS2-Co) using a molybdenum disulfide nanosheet (MoS2) and a cobalt complex of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (Codota). Evidenced by detailed experimental and theoretical studies, the NIR-enhanced MoS2-Co can circumvent the restriction by simultaneously inhibition of β-sheet formation and destroying β-sheet structures of the preformed Aβ aggregates in living cell. Furthermore, our designed MoS2-Co is an easy to graft Aβ-target agent that prevents misdirected or undesirable hydrolysis reactions, and has been demonstrated to cross the blood brain barrier. This method can be adapted for hydrolysis of other kinds of amyloids. 相似文献
129.
Shengran Li Xinxin Yan Yangchun Qu Wenliang Wang Binggang Chen Xiaojing Ma Prof. Dr. Sanrong Liu Prof. Dr. Xifei Yu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(44):10375-10384
The ester bond as a universal linker has recently been applied in gene delivery systems owing to its efficient gene release by electrostatic repulsion after its cleavage. However, the ester bond is nonlabile and is difficult to cleave in cells. This work reports a method in which a secondary amine was introduced to the β-position of the ester bond to generate a hydrogen-bond cyclization (HBC) structure that can make the ester bond hydrolysis ultrafast. A series of molecules comprising ultrasensitive esters that can be activated by H2O2 were synthesized, and it was found that those able to form an HBC structure showed complete ester hydrolysis within 5 h in both water and phosphate-buffered saline solution, which was several times faster than other methods reported. Then, a series of amphiphilic poly(amidoamine) dendrimers were constructed, comprising the ultrasensitive ester groups for gene delivery; it was found that they could effectively release genes under quite a low concentration of H2O2 (<200 μm ) and transport them into the nucleus within 2 h in Hela cells with high safety. Their gene transfection efficiencies were higher than that of PEI25k. The results demonstrated that the hydrogen-bond-induced ultrasensitive esters could be powerfully applied to construct gene delivery systems. 相似文献
130.