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991.
颈椎Modic改变与轴性疼痛的关系 总被引:1,自引:0,他引:1
目的:探讨颈椎病患者椎体终板Modic改变的发病情况及临床价值.方法:回顾分析136例颈椎病患者的颈椎MRI矢状位图像资料,记录椎体终板Modic改变的发生率、类型、各节段分布及各分布节段类型,统计并分析Modic改变与颈部轴性疼痛的关系.结果:136例颈椎病患者中有23例存在Modic改变.发生率为16.9%;男性患者中发生率为17.7%,女性为15%;最常出现Modic改变的节段为C56;Modic Ⅰ型、Ⅱ型和Ⅲ型的发生率分别为4.4%、7.4%、5.1%.存在Modic改变的患者中.轴性疼痛发生率为56.5%.术后缓解率为76.9%;无Modic改变者轴性疼痛的发生率为20.4%,术后缓解率为73.9%,两者轴性疼痛发生率有显著性差异(PO.05).Modic改变Ⅰ、Ⅱ、Ⅲ型患者中轴性疼痛发生率分别为83.3%、60%和28.6%,术后缓解率分别为100%、66.7%和50%;Modic改变I型患者轴性疼痛发生率和术后缓解率均较其他两型为高(P相似文献
992.
993.
Jingjing Yan Weidong Fei Qianqian Song Yao Zhu Na Bu Li Wang Mengdan Zhao Xiaoling Zheng 《Drug delivery》2022,29(1):2296
The emerging cell membrane (CM)-camouflaged poly(lactide-co-glycolide) (PLGA) nanoparticles (NPs) (CM@PLGA NPs) have witnessed tremendous developments since coming to the limelight. Donning a novel membrane coat on traditional PLGA carriers enables combining the strengths of PLGA with cell-like behavior, including inherently interacting with the surrounding environment. Thereby, the in vivo defects of PLGA (such as drug leakage and poor specific distribution) can be overcome, its therapeutic potential can be amplified, and additional novel functions beyond drug delivery can be conferred. To elucidate the development and promote the clinical transformation of CM@PLGA NPs, the commonly used anucleate and eukaryotic CMs have been described first. Then, CM engineering strategies, such as genetic and nongenetic engineering methods and hybrid membrane technology, have been discussed. The reviewed CM engineering technologies are expected to enrich the functions of CM@PLGA for diverse therapeutic purposes. Third, this article highlights the therapeutic and diagnostic applications and action mechanisms of PLGA biomimetic systems for cancer, cardiovascular diseases, virus infection, and eye diseases. Finally, future expectations and challenges are spotlighted in the concept of translational medicine. 相似文献
994.
Jianian Hu Ye Tan Xuemei Li Youlin Zhu Guoqiang Luo Jian Zhang Ruizhi Zhang Yi Sun Qiang Shen Lianmeng Zhang 《Materials》2022,15(14)
With the need of developing new materials, exploring new phenomenon, and discovering new mechanisms under extreme conditions, the response of materials to high-pressure compression attract more attention. However, the high-pressure state deviating from the Hugoniot line is difficult to realize by conventional experiments. Gas gun launching graded materials could reach the state. In our work, the corresponding Al-Cu composites and graded materials are prepared by tape casting and hot-pressing sintering. The microstructure and the acoustic impedance of the corresponding Al-Cu composites are analyzed to explain the impact behavior of Al-Cu graded materials. Computed tomographic testing and three-dimension surface profilometry machine results demonstrated well-graded structure and parallelism of the graded material. Al-Cu GMs with good parallelism are used to impact the Al-LiF target at 2.3 km/s using a two-stage light-gas gun, with an initial shock impact of 20.6 GPa and ramping until 27.2 GPa, deviating from the Hugoniot line. 相似文献
995.
To deeply understand the adsorption process of oxygen on the surface of a plutonium gallium system and to reveal the chemical reaction mechanism at the initial stage of oxidative corrosion on the surface of plutonium gallium alloy at a theoretical level, the adsorption behavior of oxygen molecules on the surface of a plutonium gallium system was investigated by a first-principles approach based on density flooding theory. The results show that the molecular bond length increases and finally breaks when the surface oxygen molecule is adsorbed on the surface of plutonium gallium system and dissociates into two atomic states. The most likely adsorption position of oxygen molecules on the surface of plutonium gallium system is hole-site vertical adsorption with the adsorption energy size of 10.7 eV. The bonding between oxygen atom and surface is mainly due to the overlapping hybridization of Pu-6s, Pu-7s, Pu-6d, Ga-3d and O-2p orbitals. Oxygen molecules mainly interact with the atoms of the first layer on the surface of the plutonium gallium system. The oxygen atoms after stable adsorption are able to diffuse to the subsurface of the plutonium gallium system after overcoming the energy barrier of 16.7 eV and form a stable structure. The research results reveal the initial reaction process and adsorption law of oxygen on the surface of plutonium gallium system from microscopic level, which is helpful to further explore the surface corrosion prevention technology of plutonium gallium system and improve the reliability and safety of plutonium gallium alloy components. 相似文献
996.
摘 要 目的:建立益安宁丸的HPLC指纹图谱,并测定5种主要成分(人参皂苷Rg1、人参皂苷Rb1、三七皂苷R1、五味子酯甲和丹参酮ⅡA)的含量,为益安宁丸的质量控制提供可靠方法。 方法: 采用Waters Sunfire TM C18色谱柱(250 mm×4.6 mm,5 μm),以乙腈(A) 0.1%磷酸水溶液(B)为流动相,梯度洗脱(0~5 min,2% A;5~15 min,2%A→10%A;15~25 min,10%A→30%A;25~40 min,30% A;40~60 min,30% A→90% A;60~70 min,90% A);流速为1.0 ml·min-1;检测波长为203 min(0~60 min,检测人参皂苷Rg1、人参皂苷Rb1、三七皂苷R1和五味子酯甲)、270 nm(60~70 min,检测丹参酮ⅡA);柱温35 ℃。 结果: 在指纹图谱研究中,共确定益安宁丸HPLC指纹图谱26个共有峰,通过与混合对照品比较指认其中7个指标成分,分别是6号 五味子酯甲、16号 人参皂苷Rg1、17号 人参皂苷Rb1、18号 三七皂苷R1、23号 丹参酮Ⅰ、24号 五味子甲素和26号 丹参酮ⅡA,利用相似度软件对14批样品指纹图谱进行分析,各批样品相似度均在0.98以上。在建立的色谱条件下试验5个成分分离度良好,方法精密度和重复性RSD值均<1.5%,供试品溶液在24 h内稳定,各成分具有良好的线性关系和较宽线性范围;6批益安宁丸中人参皂苷Rg1、人参皂苷Rb1、三七皂苷R1、五味子酯甲和丹参酮ⅡA质量分数分别在7.187 0~7.254 0,9.086 0~9.250 0,2.109 0~2.288 0,11.208 0~11.338 0和1.374 0~1.458 0 mg·g-1。 结论: 所建立的益安宁丸HPLC指纹图谱检测和定量测定分析方法快速、准确,可以有效地评价益安宁丸的质量。 相似文献
997.
抗生素西索米星发酵过程中次要组分的调控 总被引:2,自引:2,他引:2
在西索米星产生菌橄榄星孢小单孢菌M-41的发酵代谢与产物合成的研究中,发现通过控制种子期菌丝的生长形态、培养基中磷酸盐含量,并在发酵过程中添加合适的抑制剂,可有效地减少发酵液中次要组分verdamicin的生物合成,增加主要组分西索米星的含量。 相似文献
998.
BSA-loaded mcirospheres were prepared by a modified phase separation method, in which petroleum ether (PE) containing a certain amount of Span 80 rather than poly (dimethylsiloxane) (PDMS) was adopted as coacervating agent. Process parameters such as Span 80 concentration, the volume and addition rate of coacervating agent, polymer concentration, agitation rate during the phase separation process and PE type were evaluated to optimize the protein encapsulation. It was found microspheres with high yield (>80.0%) and entrapment efficiency (>90%) could be obtained using PE containing 5.0% Span 80 as the coacervating agent. Microspheres with small particle size (<10?µm) could be produced successfully with appropriate process parameters. In vitro release study suggested that burst release was significantly influenced by Span 80 concentration, polymer concentration and PE type and the burst release could be reduced to <20% with optimized formulation. A biphasic release behavior in vitro test was observed for the microspheres prepared by this method. GC analysis demonstrated that residual solvent of DCM and petroleum ether was decreased dramatically in comparison with PDMS used as a conventional coacervating agent. 相似文献
999.