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91.
《Bioscience, biotechnology, and biochemistry》2013,77(10):2092-2095
We report on the development of azide-coronatine as a useful platform for azide alkyne cycloaddition (“click chemistry”)-mediated synthesis of molecular probes. (+)-Azido-coronatine was synthesized in 10 steps with 11% yield using improved synthesis of coronafacic acid, in which the highly exo-selective Diels-Alder reaction (endo:exo > 1:25) is the key step. Azido coronatine was as effective as the original coronatine in a stomatal opening assay, and was easily modified to a fluorescein isothiocyanate (FITC)-labeled probe with high yield. 相似文献
92.
《Bioscience, biotechnology, and biochemistry》2013,77(11):2254-2256
Palatine chrome black 6BN (PCB6BN) is virtually non-fluorescent in an aqueous solution or in the presence of single-stranded DNA (ssDNA), whereas the fluorescence intensity of PCB6BN was linearly enhanced up to 300 μM of double-stranded DNA (dsDNA) base pairs. PCB6BN could be a useful fluorescent probe for quantifying dsDNA even when ssDNA is present for both heterogeneous and homogeneous assays. 相似文献
93.
Critical Role of Grain Boundaries for Ion Migration in Formamidinium and Methylammonium Lead Halide Perovskite Solar Cells
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94.
Sayaka Nakashima Zhe Liu Yuya Yamaguchi Shunya Saiki Shintaro Munemasa Toshiyuki Nakamura Yoshiyuki Murata Yoshimasa Nakamura 《Biochemistry and Biophysics Reports》2016
3,4-Dihydroxyphenylacetic acid (DOPAC) is one of the colonic microflora-produced catabolites of quercetin 4′-glucoside (Q4′G). Although the interaction of DOPAC with cellular proteins might be involved in its biological activity, the actual proteins have not yet been identified. In this study, we developed a novel tag-free DOPAC probe to label the targeted proteins by the copper(I)-catalyzed azide alkyne cycloaddition (CuAAC) and verified its efficacy. Various labeled proteins were detected by the DOPAC probe with the azide labeled biotin and a horseradish peroxidase (HRP)-streptavidin complex. Furthermore, a pulldown assay identified Keap1 and aryl hydrocarbon receptor (AhR) as the target proteins for the phase 2 enzyme up-regulation. 相似文献
95.
MicroRNA (miRNA) plays vital roles in various biological processes. In general, sensitivity and specificity are the major parameters for the quantification of miRNA. In this study, padlock probe–rolling circle amplification and Förster resonance energy transfer (pRCA–FRET) were coupled for specific and quantitative detection of miRNA. pRCA–FRET showed superior specificity to differentiate single-base mismatch and excellent sensitivity with a detection limit of 103 aM. The current method has the potential to quantify low amounts of miRNA in the same family for studies on their biological functions. 相似文献
96.
Methods including spectroscopy, electronic chemistry and thermodynamics were used to study the inclusion effect between γ-cyclodextrin (CD) and vitamin K3(K3), as well as the interaction mode between herring-sperm DNA (hsDNA) and γ-CD-K3 inclusion complex. The results from ultraviolet spectroscopic method indicated that VK3 and γ-CD formed 1:1 inclusion complex, with the inclusion constant Kf = 1.02 × 104 L/mol, which is based on Benesi–Hildebrand's viewpoint. The outcomes from the probe method and Scatchard methods suggested that the interaction mode between γ-CD-K3 and DNA was a mixture mode, which included intercalation and electrostatic binding effects. The binding constants were K θ25°C = 2.16 × 104 L/mol, and Kθ37°C = 1.06 × 104 L/mol. The thermodynamic functions of the interaction between γ-CD-K3 and DNA were ΔrHmθ = ?2.74 × 104 J/mol, ΔrSmθ = 174.74 J·mol?1K?1, therefore, both ΔrHmθ (enthalpy) and ΔrSmθ (entropy) worked as driven forces in this action. 相似文献
97.
Andrii K. Melnyk Olexandr V. Sukhoveev Lyudmyla A. Kononets Olexandr M. Khilchevsky Valery P. Kukhar 《Journal of liposome research》2016,26(1):80-86
Comparative properties of lecithin-based liposomes prepared from the mixed phospholipids of sunflower seeds, soybean and egg yolk were investigated by electron paramagnetic resonance (EPR) spectroscopy. For these investigations, stable nitroxide radicals, 1-oxyl-2,2,6,6-tetramethylpiperidin-4-yl 5,7-dimethyladamantane-1-carboxylate (DMAC-TEMPO), 5-doxylstearic acid (5-DSA) and 16-doxylstearic acid (16-DSA) were used as spin probes. Binding of the spin probes to the liposome membranes resulted in a substantial increase of the apparent rotational diffusion correlation times. The EPR spectra of the incorporated nitroxides underwent temperature-dependent changes. For every spin probe, values of apparent enthalpy and entropy of activation were calculated from the temperature dependence of rotational diffusion correlation times via Arrhenius equation. In case of DMAC-TEMPO, the data point to differences between the phospholipid bilayer of liposomes derived from sunflower and soy lecithin, and some similarity between the sunflower and egg yolk liposomes. Anisotropic hyperfine interaction constants of DMAC-TEMPO and 16-DSA included in the liposomes have been analyzed and attributed to different micropolarity of the surroundings of the spin probes. The kinetics of EPR signal decay of DMAC-TEMPO in the presence of 2,2′-azobis(2-amidinopropane) suggest the better stability of the sunflower liposomes to lipid peroxidation as compared to the liposomes prepared from soy lecithin. 相似文献
98.
《Bioorganic & medicinal chemistry》2016,24(18):4129-4137
Efficient strand invasion by a linear probe to fluorescently label double-stranded DNA has been implemented by employing a probe and unmodified PNA. As a fluorophore, we utilized ethynylperylene. Multiple ethynylperylene residues were incorporated into the DNA probe via a d-threoninol scaffold. The ethynylperylene did not significantly disrupt hybridization with complementary DNA. The linear probe self-quenched in the absence of target DNA and did not hybridize with PNA. A gel-shift assay revealed that linear probe and PNA combination invaded the central region of double-stranded DNA upon heat-shock treatment to form a double duplex. To further suppress the background emission and increase the stability of the probe/DNA duplex, a probe containing anthraquinones as well as ethynylperylene was synthesized. This probe and PNA invader pair detected an internal sequence in a double-stranded DNA with high sensitivity when heat shock treatment was used. The probe and PNA pair was able to invade at the terminus of a long double-stranded DNA at 40 °C at 100 mM NaCl concentration. 相似文献
99.
《Bioorganic & medicinal chemistry》2016,24(18):4272-4280
A common method of evaluating cellular proliferation is to label DNA with chemical probes. 5-Ethynyl-2′-deoxyuridine (EdU) is a widely utilized chemical probe for labeling DNA, and upon incorporation, EdU treatment of cells is followed by a reaction with a small molecule fluorescent azide to allow detection. The limitations when using EdU include cytotoxicity and a reliance on nucleoside active transport mechanisms for entry into cells. Here we have developed six novel EdU pro-labels that consist of EdU modified with variable lipophilic acyl ester moieties. This pro-label:chemical probe relationship parallels the prodrug:drug relationship that is employed widely in medicinal chemistry. EdU and EdU pro-labels were evaluated for their labeling efficacy and cytotoxicity. Several EdU pro-label analogues incorporate into DNA at a similar level to EdU, suggesting that nucleoside transporters can be bypassed by the pro-labels. These EdU pro-labels also had reduced toxicity compared to EdU. 相似文献
100.
Design and synthesis of new fluorescence probes with good water‐solubility is of great importance to better understanding the significant role of ions which are related to biology and the environment. As important ions, zinc ion (Zn2+) and dihydrogen phosphate ion (H2PO4?) display essential roles in living systems, and quantitative detection of these ions in water is still a challenge. In order to consider the significant role of the galactose moiety in the design of a water‐soluble fluorescence sensor, herein, we have developed a novel probe, Gal‐AQTF, for the cascade detection of Zn2+ and H2PO4? with excellent selectivity in water. Through the introduction of the galactose moiety onto the sensor AQTF, which has been reported earlier by us, the water‐solubility, cell compatibility and targeting ability were enhanced. Gal‐AQTF has been successfully applied in the imaging of the living cells of HepG2 and A549, and illustrated good selectivity for the HepG2 cells which overly express the asialoglycoprotein (ASGP) receptor. 相似文献