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Introduction: Conformational diseases are caused by structurally abnormal proteins that cannot fold properly and achieve their native conformation. Misfolded proteins frequently originate from genetic mutations that may lead to loss-of-function diseases involving a variety of structurally diverse proteins including enzymes, ion channels, and membrane receptors. Pharmacoperones are small molecules that cross the cell surface plasma membrane and reach their target proteins within the cell, serving as molecular scaffolds to stabilize the native conformation of misfolded or well-folded but destabilized proteins, to prevent their degradation and promote correct trafficking to their functional site of action. Because of their high specificity toward the target protein, pharmacoperones are currently the focus of intense investigation as therapy for several conformational diseases.

Areas covered: This review summarizes data on the mechanisms leading to protein misfolding and the use of pharmacoperone drugs as an experimental approach to rescue function of distinct misfolded/misrouted proteins associated with a variety of diseases, such as lysosomal storage diseases, channelopathies, and G protein-coupled receptor misfolding diseases.

Expert commentary: The fact that many misfolded proteins may retain function, offers a unique therapeutic opportunity to cure disease by directly correcting misrouting through administering pharmacoperone drugs thereby rescuing function of disease-causing, conformationally abnormal proteins.  相似文献   

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This study aimed to evaluate growth factor concentration in platelet-rich plasma (PRP) (leukocyte-rich PRP) based on storage temperature, duration of storage, and method of activation. PRP samples were stored at 24℃ (room temperature group), 4℃ (refrigerator group), and −70℃ (deep-freezer group). In each temperature, four aliquots were prepared based on the time of analysis (immediately, 1, 3, and 7 days after preparation). After storage, concentrations of platelet-derived growth factor-AA (PDGF-AA), transforming growth factor-β (TGF-β), vascular endothelial growth factor (VEGF), insulin-like growth factor-1 (IGF-1), and fibroblast growth factor-basic (FGF-B) were assessed with/without activation using Quantikine colorimetric sandwich immunoassay kits. PRP was activated with 10% Triton-X for PDGF-AA, VEGF, FGF-B, IGF-1 measurement and sonication for TGF-β1 measurement. Without activation, PDGF-AA concentration was highest on day 7 in the room temperature group. With activation, the concentration of PDGF-AA was constant over the observation period at all temperatures. Without activation, the TGF-β1 concentration remained negligible over the observation period at all temperatures. However, with activation, TGF-β1 gradually increased to its highest concentration on day 7 at all temperatures. Over the observation period, VEGF and IGF-1 concentrations were constant with and without activation at all temperatures. Without activation, FGF-B concentration increased, with the highest concentration observed on day 7 in the deep-freezer group. With activation, FGF-B concentration decreased after day 1 in the room temperature group. Growth factor concentration in PRP differed significantly based on storage temperature, duration of storage, and method of activation. Appropriate storage conditions and activation are important to optimize its effects on desired clinical outcomes. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:777-784, 2020  相似文献   
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目的 改善药品保存现状,保证官兵用药安全。方法 根据野外作战的环境特点,分析影响药品质量的因素。结果 药品质量受环境温度、湿度、空气、光线等影响较大,尤其是部队在野外遂行任务时,条件复杂多变,环境指标人为无法控制,若不能很好地贮藏,就容易出现质量问题。结论 药品作为一种特殊物资,在医疗保障工作中有着不可替代的作用,质量过硬的药品可以促进患者伤病早日康复,提高保障能力,进而提升部队的战斗力。  相似文献   
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Coherence is a major caveat in quantum computing. While phonons and electrons are weakly coupled in a glass, topological insulators strongly depend on the electron-phonon coupling. Knowledge of the electron−phonon interaction at conducting surfaces is relevant from a fundamental point of view as well as for various applications, such as two-dimensional and quasi-1D superconductivity in nanotechnology. Similarly, the electron−phonon interaction plays a relevant role in other transport properties e.g., thermoelectricity, low-dimensional systems as layered Bi and Sb chalcogenides, and quasi-crystalline materials. Glass-electrolyte ferroelectric energy storage cells exhibit self-charge and self-cycling related to topological superconductivity and electron-phonon coupling; phonon coherence is therefore important. By recurring to ab initio molecular dynamics, it was demonstrated the tendency of the Li3ClO, Li2.92Ba0.04ClO, Na3ClO, and Na2.92Ba0.04ClO ferroelectric-electrolytes to keep phonon oscillation coherence for a short lapse of time in ps. Double-well energy potentials were obtained while the electrolyte systems were thermostatted in a heat bath at a constant temperature. The latter occurrences indicate ferroelectric type behavior but do not justify the coherent self-oscillations observed in all types of cells containing these families of electrolytes and, therefore, an emergent type phenomenon where the full cell works as a feedback system allowing oscillations coherence must be realized. A comparison with amorphous SiO2 was performed and the specific heats for the various species were calculated.  相似文献   
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The use of phase change materials (PCMs) is an attractive method for energy storage and utilization in building envelopes. Here, shape-stabilized phase change materials (SS-PCMs) were prepared via direct adsorption using mesoporous silica (MS) with different pore diameters as the support matrix. The leakage properties, microstructure, chemical structure, thermophysical properties, activation energy, thermal stability and thermal storage-release characteristics of paraffin and SS-PCMs were investigated. The results show that the maximum mass proportion of paraffin in SS-PCMs is 70% when the average pore diameter of mesoporous silica is 15 nm, and the phase change temperature and latent heat of the corresponding SS-PCM are 23.6 °C and 135.4 kJ/kg, respectively. No chemical reaction occurs between mesoporous silica and paraffin and the SS-PCMs exhibit high thermal stability. The high activation energy of the paraffin (70%)/MS1 SS-PCM verifies that the shape and thermal properties can be maintained stably during phase change conversions. The time required for SS-PCMs to complete the thermal storage and release process is reduced by up to 34.0% compared with that for pure paraffin, showing a decline in the thermal conductivity of SS-PCMs after the addition of mesoporous silica. Hence, the prepared paraffin/MS SS-PCMs, in particular paraffin (70%)/MS1 SS-PCM, can be used for storing thermal energy and regulating indoor temperature in buildings.  相似文献   
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Magnesium-based alloys are attractive as hydrogen storage materials due to their lightweight and high absorption, but their high operating temperatures and very slow kinetics are obstacles to practical applications. Therefore, the effect of CaO has improved the hydrogenation kinetics and slowed down the degradation. The Mg2NiHx–CaO composites were prepared by hydrogen-induced mechanical alloying (HIMA). Hydrogenation kinetics was performed by using an Automatic PCT Measuring System and evaluated in the temperature range of 423, 523, and 623 K. As a result of calculating the hydrogen absorption amounts through the hydrogenation kinetics curve, they were calculated as about 0.52 wt%, 1.21 wt%, and 1.59 wt% (Mg2NiHx–10 wt% CaO). In this study, the material environmental aspects of Mg2NiHx–CaO composites were investigated through life cycle assessment (LCA). LCA was performed analyzing the environmental impact characteristics of the manufacturing process by using Gabi software and the Eco-Indicator 99’ and Centrum voor Milieuweten schappen (CML 2001) methodology. As a result, the contents of global warming potential (GWP) and fossil fuels were found to have a higher impact than other impact categories.  相似文献   
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