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141.
We study the scattering of a non-Abelian dyon and photons. We demonstrate thattwo photons are necessary for Compton scattering of a non-Abelian dyon, throughS-matrix expansion. One of these two photons is associated with electric four-potentialand is ordinary, while the other is associated with magnetic four-potentialand is highly energetic and responsible for scattering of magnetic charge of thenon-Abelian dyon. We also study dyon—photon, dyon—dyon, and dyon—antidyonscattering and the self-energy of the dyon and both photons in non-Abeliangauge theories.  相似文献   
142.
Inspired by the availability of recent experimental as well as theoretical data on the energy levels of odd-mass 151-161Pm and odd-odd 154,156Pm, we applied the theoretical framework of the projected shell model to further understand the nuclear structure of these nuclei. The calculations closely reproduced the experimental data reported for the yrast bands of these isotopes by assuming an axial (prolate) deformation of ~0.3. Other properties along the yrast line, such as transition energies and transition probabilities, have also been discussed. Band diagrams are plotted to understand their intrinsic multi-quasiparticle structure, which turn out to be dominated by 1-quasiparticle bands for the odd-mass Pm isotopes and 2-quasiparticle bands for the doubly-odd Pm isotopes under study. The present study not only confirms the recently reported experimental/theoretical data, but also extends the already available information on the energy levels and adds new information regarding the reduced transition probabilities.  相似文献   
143.
The excessive production of endogenous hydrogen sulfide (H2S) in cancer cells leads to enhanced tumor growth and metastasis. On the other hand, decreased endogenous H2S suppresses tumor growth. The reported approaches for inhibiting tumor growth are selective silencing of the tumor-promoting genes and pharmacological inhibition of these proteins. To enhance the antitumor efficacy of frontline chemotherapeutic agents, herein, we synthesized a highly sensitive endogenous H2S responsive fluorescent probe, i.e., a hydrogen sulfide-sensing naphthalimide-based peptide conjugate (HSNPc), which showed selective inhibition of proliferation of cancer cells due to apoptosis induction. Furthermore, HSNPc suppressed the glycolytic reserve, a critical energy source for the proliferation of cancer cells. HSNPc also decreased the Young''s modulus of HeLa cells compared to the control cells, which demonstrated a direct relation between cell apoptosis and cell stiffness. Taken together, we demonstrated the dual function of detection and killing of cancer cells by HSNPc that can be likened to a theranostic role.

A hydrogen sulfide sensing naphthalimide based peptide conjugate (HSNPc) worked as a novel cancer cell imaging agent and showed selective cell apoptosis.  相似文献   
144.
Currently, particular interest among the scientific community is focused on exploring the use of exosomes for several pharmaceutical and biomedical applications. This is due to the identification of the role of exosomes as an excellent intercellular communicator by delivering the requisite cargo comprising of functional proteins, metabolites and nucleic acids. Exosomes are the smallest extracellular vesicles (EV) with sizes ranging from 30–100 nm and are derived from endosomes. Exosomes have similar surface morphology to cells and act as a signal transduction channel between cells. They encompass different biomolecules, such as proteins, nucleic acids and lipids, thus rendering them naturally as an attractive drug delivery vehicle. Like the other advanced drug delivery systems, such as polymeric nanoparticles and liposomes to encapsulate drug substances, exosomes also gained much attention in enhancing therapeutic activity. Exosomes present many advantages, such as compatibility with living tissues, low toxicity, extended blood circulation, capability to pass contents from one cell to another, non-immunogenic and special targeting of various cells, making them an excellent therapeutic carrier. Exosome-based molecules for drug delivery are still in the early stages of research and clinical trials. The problems and clinical transition issues related to exosome-based drugs need to be overcome using advanced tools for better understanding and systemic evaluation of exosomes. In this current review, we summarize the most up-to-date knowledge about the complex biological journey of exosomes from biogenesis and secretion, isolation techniques, characterization, loading methods, pharmaceutical and therapeutic applications, challenges and future perspectives of exosomes.  相似文献   
145.
Designs, Codes and Cryptography - A code is said to have locality r if any coordinate value in a codeword of that code can be recovered by at most r other coordinates. In this paper, we have...  相似文献   
146.
An artificially engineered structure of nano-inclusion made of metallic nano-rods embedded in a dielectric (ε=12.96) matrix with hexagonal arrangement is proposed to demonstrate All-angle Negative Refraction (AANR) for the visible region. AANR with negative index is obtained by applying Surface Plasmon Polariton Excitation (SPPE) in Metallo-Dielectric Photonic Crystal (MDPC) operating in a dispersion regime with anti-parallel refracted wave vector and Poynting vector. It is shown that the proposed MDPC structure provides negative values of permeability (μ) and permittivity (ε) and shows their dependence on its structural parameters. The phase slope and phase velocity are shown to be negative for blue light in the proposed MDPC with index-matching to the incident medium. The Finite Difference Time Domain (FDTD) method is employed to study the left-handed transmission and reflection properties. The far-field spectrum for the proposed MDPC is also shown to confirm left-handed transmission for the blue region of visible light. Further, the proposed design of MDPC is also extended to achieve negative refraction for all rainbow colors having applications in the design and development of nanophotonic devices.  相似文献   
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149.
A gradient-specific stability indicating HPLC method was developed and validated for the determination of the antidiabetic agent anagliptin in laboratory mixtures. Reversed-phase chromatography was performed using a Shimadzu LC-20 AD pump (binary), Shimadzu PDA M-20A diode array detector, and Waters Symmetry C-18 column (150?×?4.6 mm, 3.5 µm) maintained at a column oven temperature of 40 °C with UV detection at 247 nm. A gradient program was run at flow rate of 1 mL min?1. Mobile phase A consisted of a mixture of acetate buffer(10 mm) pH 5/methanol/acetonitrile in the ratio of 90:5:5. Mobile phase B consisted of a mixture of acetate buffer (10 mm) pH 5/methanol/acetonitrile in the ratio of 50:25:25. The method was validated according International Conference of Harmonization (ICH) guidelines. Linearity was observed in the concentration range of 10–120 µg/mL with regression coefficient r2(0.999). The LOD was found to be 7.8 µg/mL and LOQ was found to be 22.68 µg/mL. Anagliptin was subjected to stresses such as acidic, alkali, oxidation, photolysis, and thermal conditions. The proposed method was validated as per ICH guidelines and was found to be accurate, precise, and specific. The drug showed significant degradation in alkaline and oxidative conditions. Alkaline and oxidative degradation followed first-order kinetics. Degradation rate constant and half-lives were determined. Degradation products in alkaline and oxidative conditions were identified by LC–MS. One major degradation product was isolated from each condition by preparative HPLC. These degradation products were characterized by 1H NMR, 13C NMR, DEPT, D2O exchange, MS/MS, HRMS, and IR techniques. From the spectral data the alkaline degradation product was characterized as 1-{2-[1-(2-methylpyrazolo[1,5-a]pyrimidine-6-carboxamido)-methyl-propan-2-yl-amino]acetyl}pyrrolidine-2-carboxamide. The oxidative degradation product was characterized as N-[2-({2-[(2S)-2-cyanopyrrolidin-1-yl]-2-oxoethyl}amino)-2-methylpropyl]-2-methylpyrazolo-[1,5-a]pyrimidine-N-oxido-6-carboxamide.  相似文献   
150.
A manganite matrix-based composite series, (1 ? x)La0.67Ca0.33MnO3(LCMO) ? (x)SrTiO3 (STO), has been prepared by the solid state route. Influence of STO phase on structural and magneto-transport properties of LCMO phase has been investigated. By X-ray diffraction, scanning electron microscopy, and Fourier transform of infrared spectroscopy, we find that there is no interdiffusion between the LCMO and STO phases. Measurements of resistivity on these samples reveal that the parent sample shows a distinct metal–insulator (M–I) transition of intrinsic type at a temperature close to the Curie temperature, whereas composite samples show two possible transitions, intrinsic as well as extrinsic. The series exhibits a conduction threshold at x = x m ~ 20%, up to which extrinsic M–I transition temperature decreases along with an increase in extrinsic magnetoresistance; whereas, above x m these trends of variation are reversed.  相似文献   
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