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11.
指纹图谱法在参麦注射液质控中的应用 总被引:8,自引:4,他引:8
中医药理论和实践要求综合评价中药的质量 ,指纹图谱法是对中药制剂进行综合宏观分析的可行手段之一 ,因此采用反相高效液相建立了参麦注射液的特征指纹图谱。条件 :Hypersil C18(4 6mmi d × 2 5 0mm ,5 μm)反相柱 ,流动相由水 (A)和乙腈 (B)组成 ,B的体积分数在 5 0min内由 5 %线性增长到 95 % ,流速为1 0mL/min ;紫外检测 ,波长为 2 0 2nm。 2 3个特征指纹峰与内标 (联苯 )的峰面积比作为指标 ,结合主成分分析 投影判别法比较了同一厂家不同批次产品和不同厂家同类产品的化学指纹差异。 相似文献
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Investigations have been performed on convective heat transfer in water flowing through mini-channels using the non intrusive technique of laser interferometry coupled with digital image processing. Optical glass channels, fabricated with metallic heating surfaces, were studied using a Mach-Zehnder interferometer configuration. Fringe patterns captured using a high-sensitivity CCD camera were analyzed digitally based on a calculation method developed for the liquid medium. Results of parametric studies were compared and contrasted with relevant theoretical solutions from the literature. Indication of the onset of turbulence at Reynolds numbers smaller than the conventional transition Reynolds number for large channels has also been noticed in the experimental investigation. 相似文献
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Jing Liu Xiu‐Mei Li Dong‐dong Shi Zhi‐guo Wen Pei‐Long Yang 《Biomedical chromatography : BMC》2019,33(12)
In recent years, the fingerprint of high‐performance liquid chromatography has been extensively applied in the identification and quality control of traditional Chinese medicine. It can be a potential protocol for assessing the authenticity, stability and consistency of traditional Chinese medicine and guaranteeing the expected biological activity. In this paper, a method using high‐performance liquid chromatography to identify and control the quality of the extract of Taraxacum mongolicum Hand.‐Mazz. (TME) was established. With this method, the correlation coefficients of the similarity of 10 batches were ≥0.994. The TME displayed a steady proliferative effect in Lactobacillus plantarum. In brief, this study successfully built a reliable, simple and efficient method to control and confirm the quality and the stability of biological activity of the TME. 相似文献
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G-quadruplexes (G4) are the most actively studied non-canonical secondary structures formed by contiguous repeats of guanines in DNA or RNA strands. Small molecule mediated targeting of G-quadruplexes has emerged as an attractive tool for visualization and stabilization of these structures inside the cell. Limited number of DNA and RNA G4-selective assays have been reported for primary ligand screening. A combination of fluorescence spectroscopy, AFM, CD, PAGE, and confocal microscopy have been used to assess a dimeric carbocyanine dye B6,5 for screening G4-binding ligands in vitro and in cellulo. The dye B6,5 interacts with physiologically relevant DNA and RNA G4 structures, resulting in fluorescence enhancement of the molecule as an in vitro readout for G4 selectivity. Interaction of the dye with G4 is accompanied by quadruplex stabilization that extends its use in primary screening of G4 specific ligands. The molecule is cell permeable and enables visualization of quadruplex dominated cellular regions of nucleoli using confocal microscopy. The dye is displaced by quarfloxin in live cells. The dye B6,5 shows remarkable duplex to quadruplex selectivity in vitro along with ligand-like stabilization of DNA G4 structures. Cell permeability and response to RNA G4 structures project the dye with interesting theranostic potential. Our results validate that B6,5 can serve the dual purpose of visualization of DNA and RNA G4 structures and screening of G4 specific ligands, and adds to the limited number of probes with such potential. 相似文献
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《Biomedical chromatography : BMC》2018,32(6)
Salvia miltiorrhiza Bge. is a traditional Chinese medicine applied in the treatment of various diseases in clinical practice. In the course of its processing, S. miltiorrhiza Bge. is usually processed by sweating. This study employed 10‐component contents determination coupled with high‐performance liquid chromatography (HPLC) fingerprint and antioxidant activity to investigate the effect of sweating on S. miltiorrhiza Bge. so as to evaluate the quality of S. miltiorrhiza Bge. The HPLC method was performed using C18 and 0.05% phosphoric acid aqueous solution–acetonitrile with a gradient elution system. It was validated for linearity, precision, repeatability, stability and recovery. Similarity analysis, principal components analysis and antioxidant activity assays were used to compare sweated S. miltiorrhiza Bge. (SSM) and nonsweated S. miltiorrhiza Bge. (NSSM). SSM and NSSM showed good similarities in HPLC fingerprint (>0.9), but principal components analysis could classify the HPLC fingerprint and 10‐component quantitation analysis. Meanwhile, the antioxidant activity of SSM was significantly higher than that of NSSM (p < 0.01). The results of this study indicated that sweating could alter the content of chemical constituents in S. miltiorrhiza Bge., and could also improve its antioxidant activity. In addition, the method not only affords a viable strategy for comparing SSM and NSSM and assessing the quality of S. miltiorrhiza Bge., but also provides a reference for other herbal medicine that suffers from sweating. 相似文献
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《Journal of computational chemistry》2017,38(29):2538-2552
Chemical research is assisted by the creation of visual representations that map concepts (such as atoms and bonds) to 3D objects. These concepts are rooted in chemical theory that predates routine solution of the Schrödinger equation for systems of interesting size. The method of Quantum Chemical Topology (QCT) provides an alternative, parameter‐free means to understand chemical phenomena directly from quantum mechanical principles. Representation of the topological elements of QCT has lagged behind the best tools available. Here, we describe a general abstraction (and corresponding file format) that permits the definition of mappings between topological objects and their 3D representations. Possible mappings are discussed and a canonical example is suggested, which has been implemented as a Python “Add‐On” named Rhorix for the state‐of‐the‐art 3D modeling program Blender. This allows chemists to use modern drawing tools and artists to access QCT data in a familiar context. A number of examples are discussed. © 2017 The Authors. Journal of Computational Chemistry Published by Wiley Periodicals, Inc. 相似文献
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