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21.
胃癌雌激素受体表达及新一代抗受体药物在胃癌治疗中的探讨 总被引:3,自引:0,他引:3
目的 探讨胃癌雌激素受体 (ER)实际表达率 ,为临床使用新一代抗ER药物 (toremifene ,TOR)治疗胃癌提供临床病理依据。方法 用免疫组化法对 349例胃癌标本进行ER的检测 ,其中 2 99例用ABC(avidinbiotinperoxidasecomplex)法 ,5 0例用葡聚糖聚合物技术二步法进行检测。在检测ER的同时也检测 p5 3及PCNA的表达。结果 两种检测方法的ER阳性率分别为 2 .3% (7/ 2 99)及 0 % (0 / 5 0 ) ,p5 3阳性率 37.1% (111/ 2 99)及 4 6 %(2 3/ 5 0 ) ,PCNA 94 .3% (2 82 / 2 99)及 96 % (48/ 5 0 )。结论 胃癌细胞可表达ER但实际表达率很低 ,而且存在质和量的变化。tamoxifen (TAM )及TOR的抗胃癌效应需要进一步研究 相似文献
22.
A serotonin (5-HT)-mediated phosphoinositide hydrolysis response was characterized in fibroblasts cultured from rabbit choroid plexus. 5-HT elicited a maximum 8-fold increase in [3H]inositol-phosphate ([3H]IP) formation, while the partial agonists, (+)-lysergic acid diethylamide and (−)-1-(4-bromo-2,5-dimethyoxyphenyl)-2-aminopropane caused 2- and 5-fold increases, respectively. Mianserin, ketanserin, and spiperone were equipotent at blocking the 5-HT-mediated response. Thus, agonist and antagonist profiles indicate interactions with 5-HT2 receptors. 相似文献
23.
Peter J. Morgan Lynda M. Williams Gary Davidson Wilfred Lawson Edward Howell 《Journal of neuroendocrinology》1989,1(1):1-4
The functional significance of the pars tuberalis (PT) of the mammalian adenohypophysis has remained an enigma (1, 2). One view of its function is that it acts as an auxiliary gland to support the endocrine role of the pars distalis (PD) (2), as it has been shown to contain immunocytochemically identifiable thyrotrophs and gonadotrophs (1). Many of the cells of the PT are, however, ultrastructurally unique suggesting an independent function for this tissue. Our recent demonstration that the PT of the rat is a major binding site for the ligand iodomelatonin lends further support to this idea (3). We have utilized the highly specific ligand [125 l]melatonin, and have demonstrated that it binds exclusively, with very high affinity, to the PT but not the PD of the adult sheep adenohypophysis. These findings support the conclusion that the PT has a distinct role in relation to melatonin action and seasonal reproduction. 相似文献
24.
Kazuhiko Yanai Tatsuo Ido Kiichi Ishiwata Jun Hatazawa Toshihiro Takahashi Ren Iwata Taiju Matsuzawa 《European journal of nuclear medicine and molecular imaging》1986,12(3):141-146
The endogenous hallucinogen, N,N-dimethyltryptamine (DMT), was labeled with carbon-11 and its regional distribution in rat brain studied. [11C]DMT showed higher accumulation in the cerebral cortex, caudate putamen, and amygdaloid nuclei. Studies of the subcellular distribution of [11C]DMT revealed the specific localization in the fractions enriched with serotonin receptors only when a very low dose was injected into rats. The proportions of the radioactivity in receptor-rich fractions were greatly enhanced by pretreatment with the monoamine oxidase inhibitor, pargyline. Specific binding of [11C]DMT to serotonin receptors in dog brain was demonstrated by a positron emission tomographic study in which 5-methoxy-N,N-dimethyltryptamine caused approximately 20% displacement of the radioligand from the receptors. 相似文献
25.
目的 观察人参皂苷(ginsenoside,GSS)对人肝细胞HL-7702内性激素受体水平的调节作用。方法 以四唑盐比色法(MTT)观察细胞生长以确定药物浓度,应用免疫组化法,免疫蛋白印迹法(Western blot)和RT PCR法分析人参皂苷对HL-7702细胞性激素受体蛋白和其mRNA水平的影响。结果 随GSS药物浓度增大,细胞内雌激素受体(estrogen receptor,ER)、孕激素受体(progesterone receptor,PR)、雄激素受体(androgen receptor,AR)蛋白及mRNA表达水平均逐渐增高,与溶剂对照组比较,差异有统计学意义(P<0.05),且细胞内性激素受体蛋白及mRNA表达呈剂量依赖性增加。结论 GSS可上调HL-7702细胞内性激素受体蛋白及mRNA的表达。 相似文献
26.
Bacterial ghosts (BGs) are empty bacterial envelopes of Gram-negative bacteria produced by controlled expression of cloned gene E, forming a lysis tunnel structure within the envelope of the living bacteria. BGs are devoid of cytoplasmic content and possess all bacterial bio-adhesive surface properties in their original state while not posing any infectious threat. BGs are ideally suited as an advanced drug delivery system (ADDS) for toxic substances in tumor therapy. The inner space of BGs can be loaded with either single components or combinations of peptides, drugs or DNA which provides an opportunity to design new types of (polyvalent) drug delivery vehicles. Uptake of BGs loaded with Doxorubicin (Dox) by CaCo2 cells led to effective Dox release from endo-lysosomal compartments and accumulation in the nucleus. Viability and proliferative capacity of the cells were significantly decreased (2–3 orders of magnitude) after internalization of Dox loaded BGs as compared to cells incubated with free Dox. The same effect was observed with leukemia cells. Melanoma cells also revealed a high capability to internalize BGs. These results indicate that BGs are able to target a range of types of cancer. BGs have also been investigated as DNA delivery vectors. Studies show DNA loaded BGs are efficiently phagocytosed and internalized by both professional APCs and tumor cells with up to 82% of cells expressing the plasmid-encoded reporter gene. Our studies with BGs as an ADDS system contribute (i) to optimize drug delivery for the treatment of cancer; (ii) define specific conditions for selection and preparation of BG formulations; (iii) and provide a background for the clinical application of BGs in cancer therapy. 相似文献
27.
Beyond C4d: Other Complement-Related Diagnostic Approaches to Antibody-Mediated Rejection 总被引:3,自引:0,他引:3
William M. Baldwin III Edward K. Kasper rea A. Zachary Barbara A. Wasowska E. Rene Rodriguez 《American journal of transplantation》2004,4(3):311-318
Complement is a multifunctional system of receptors and regulators as well as effector molecules. Both the pathogenic and diagnostic power of complement is based on the capacity of the complement system to amplify innate and adaptive immunity. This amplification is accomplished through two strategies: (1) enzymatic reactions in the complement cascade, and (2) stimulation of leukocytes, platelets and parenchymal cells through specific receptors or receptor-independent pore formation. The mechanisms by which complement mediates and modifies nonspecific inflammation, antibody-mediated injury and T-cell responses are of particular significance to the pathogenesis of transplant rejection. Understanding the mechanisms by which complement integrates the interactions of leukocytes, platelets and parenchymal cells offers opportunities to further refine the diagnosis of rejection. 相似文献
28.
小干扰RNA干扰大鼠神经元Nogo受体mRNA表达的实验研究 总被引:2,自引:2,他引:0
目的观察大鼠Nogo受体(NgR)特异性小干扰RNA(small interfering RNA,siRNA)在原代神经元干扰其mRNA表达的效果。方法体外培养大鼠原代皮层和海马细胞,应用阳离子脂质体转染试剂转染4对化学合成的大鼠NgR特异性siRNA,72h后提取细胞总RNA,实时荧光定量RT-PCR检测NgR mRNA表达情况。结果4对siRNA均能够下调靶基因NgR的mRNA表达水平,siNgR199、siNgR562、siNgR772和siNgR964等干扰后,NgR mRNA的表达分别为对照siRNA干扰组的6.5%、62.4%、15.2%和6.86%,与对照siRNA干扰组比较有统计学意义(P<0.05)。结论化学合成的NgR特异性siRNA能够有效的干扰大鼠原代皮层和海马细胞内NgR基因mRNA的表达水平。 相似文献
29.
湖北人群Toll样受体4基因多态性研究 总被引:5,自引:0,他引:5
目的 研究湖北人群Toll样受体4(TLR4)Asp299Gly和Thr399Ile基因多态性分布特征。方法 采用等位基因特异性聚合酶链反应(ASPCR)-限制酶片断长度多态性(RFLP)检测TLR4 Asp299Gly和Thr399 Ile基因多态性。结果 在所有的253例中国湖北人群样本中,没有检测到TLR4 Asp299Gly和Thr399Ile基因多态性存在。结论 TLR4基因多态性在不同地区和人群发生的频率是不同的,与白种人相比,中国湖北人群的TLR4Asp299G1y和Thr399Ile的基因多态性非常罕见。 相似文献
30.
雌激素及其受体与胆囊癌关系的研究现状及进展 总被引:2,自引:0,他引:2
目的:探讨并讨论雌激素及其抗体与胆囊癌的关系.方法:阅读关于雌激素和胆囊癌方面的文献并进行总结.结果:雌激素在胆囊癌转变过程中起极为重要的作用.结论:研究胆囊癌患者血清中的雌激素水平对胆囊癌的发生、发展、预后及指导相应临床内分泌治疗具有重要的理论意义. 相似文献