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31.
防风苍耳子水煎剂对小鼠免疫功能的影响 总被引:21,自引:0,他引:21
本文用ELISA法研究了防风、苍耳子水煎剂对IgE、IgG、IgM的调节作用。结果表明:防风和苍耳子水煎剂均能显著抑制DNP-BSA致敏小鼠的IgE产生(P<005),延迟和减轻卵蛋白致敏豚鼠的I型超敏反应。其中防风对IgG和IgM抗体的产生、以及细胞免疫功能都有显著的增强作用(P<005和<001),苍耳子对体液免疫作用不明显(P>005),但对细胞免疫却有抑制作用(P<001和<005)。 相似文献
32.
器官移植技术发展迅速, 但移植器官的长期存活和功能维持依旧离不开免疫抑制剂的大量使用。当前, 器官移植术后发生的排斥反应、感染等仍是移植科医师和受者需要面对的主要问题。为了进一步探究排斥反应和免疫耐受的基本生物学原理, 解答诸多临床器官移植过程中的病理生理学相关问题, 为器官移植更广泛、有效地推广应用提供基础理论依据和临床干预的指导, 器官移植领域的基础研究仍在稳步向前推进。2020年, 研究者在器官移植免疫应答基本规律、克服移植排斥反应、诱导移植免疫耐受等方面的基础研究有诸多重要进展。本文主要从免疫细胞亚群和免疫分子两大方向对2020年研究者诱导移植免疫耐受的部分新尝试和进展进行总结, 并简要展望了未来器官移植免疫学的主要发展方向。 相似文献
33.
肾移植术后早期急性排斥反应发生的风险较高,严重影响受者的生存质量。2009年,改善全球肾脏病预后组织(KDIGO)建议将免疫诱导药物纳入肾移植术前免疫诱导方案中,其目的就是针对这一关键时期提供一定强度的免疫抑制,从而有效减少术后急性排斥反应的发生。目前全球各移植中心对于免疫诱导药物的选择及其有效性、安全性仍不确定。本文通过汲取国内外学者的研究成果,对比分析单克隆抗体包括白细胞介素-2受体拮抗剂、阿伦单抗、利妥昔单抗及多克隆抗体抗胸腺细胞球蛋白在肾移植术前免疫诱导中的应用效果,旨在为推动肾移植免疫诱导药物的个体化选择,提高受者的生存质量提供参考。 相似文献
34.
35.
Gene delivery to dendritic cells by orally administered recombinant Saccharomyces cerevisiae in mice
DNA vaccination has caught the attention of many for triggering humoral as well as cellular immune responses. And delivering DNA into the antigen presenting cells (APCs) in order to induce efficient immunoresponse has become the backbone of this field. It has been confirmed that Saccharomyces cerevisiae, though non-pathogenic, is being engulfed by the dendritic cells and macrophages and delivers not only proteins, but also DNA materials (already confirmed in vitro). In this research, S. cerevisiae is used to deliver green fluorescent protein (GFP) reporter gene controlled under cytomegalovirus (CMV) promoter in living organism (mice). The recombinant yeast, transfected with the plasmid containing the GFP gene, was heat killed and orally administered to mice. After 60 h of yeast administration, mice were sacrificed and intestine was separated, washed and frozen in liquid nitrogen. Tissues were cut at the size of 10 μm using Cryostat machine, and GFP expression was successfully detected under a fluorescence microscope. After 45 days Western blot was able to detect GFP antibody in the blood of mice. These results imply that S. cerevisiae, being non-pathogenic, cheap, and easy to culture could be a good candidate to deliver DNA materials to the immune cells for vaccination. 相似文献
36.
IntroductionInfants born to mothers with placental malaria at delivery develop Plasmodium falciparum parasitemia earlier than those born to mothers without placental infection. This phenomenon may be explained by the development of immune tolerance due to exposure to P. falciparum antigens in utero. The hypothesis of this study is that this increased susceptibility might be related to infections by parasites expressing the same blood stage allele’s antigens as those to which the infants were exposed in utero.MethodsThe comparison of P. falciparum msp2 (3D7 and FC27) and glurp gene polymorphisms of infected mothers at delivery to those of their offspring’s infections during infancy was realized and the possible associations of the different polymorphisms with clinical outcomes were assessed. A second approach consisted in the use of a Geographic Information System to determine whether the antigen alleles were homogeneously distributed in the area of study. This was necessary to analyze whether the biological observations were due to high exposure to a particular antigen allelic form in the environment or to high infant permissiveness to the same allelic antigen polymorphism as the placental one.ResultsInfants born to mothers with placental malaria at delivery were more susceptible to infections by parasites carrying the same glurp allele as encountered in utero compared to distinct alleles, independently of their geographic distribution.ConclusionThe increased permissiveness of infants to plasmodial infections with shared placental-infant glurp alleles sheds light on the role that P. falciparum blood stage antigen polymorphisms may play in the first plasmodial infections in infancy. 相似文献
37.
E. Theodorsson O. Rugarn 《Scandinavian journal of clinical and laboratory investigation》2013,73(5):411-418
Galanin is a regulatory peptide with wide distribution in the central and peripheral nervous system and with numerous biological effects. Several radioimmunoassays based on antisera raised against porcine galanin have been used to measure immunoreactivity in rat tissues. However, considerable lack of parallelism has been observed between the porcine standard and rat tissue extracts, which may decrease the reliability of the quantitative data. The purpose of the present study was therefore to raise antibodies against rat galanin and establish a competitive radioimmunoassay for rat galanin. Two antisera, RatGal4 and RatGal5, were characterized in detail. The homogeneity of the immunoreactive material from several tissues was also investigated with column chromatography. At reverse-phase high-pressure liquid chromatography more than 95% of the immunoreactive material from rat CNS eluted as a single peak in the position of synthetic rat galanin, whereas almost half of the immunoreactive material from the intestine eluted in positions different from the synthetic peptide. Extracts of rat brains as well as jejunum diluted in parallel with the standard curve for both antisera. We conclude that measurements of rat galanin based on these antisera are therefore more reliable than those based on antisera raised against porcine galanin. 相似文献
38.
胃肠外营养添加精氨酸对胃癌术后患者淋巴细胞免疫功能的作用 总被引:4,自引:0,他引:4
为探讨胃肠外营养(TPN)添加精氨酸(Arg)对胃癌术后患者淋巴细胞免疫功能的影响及意义,对36例胃癌术后患者进行了TPN支持的前瞻性研究,检测常规TPN和TPN添加Arg支持前后患者的T淋巴细胞亚群、NK细胞活性、IL2和CD25水平变化。结果:常规TPN支持前后患者的T淋巴细胞亚群、NK细胞活性、IL2和CD25水平变化无明显差异,而TPN添加Arg支持后患者的CD4、CD4/CD8比值、NK细胞活性和IL2水平均明显增加(P<0.05)。本研究结果显示:常规TPN不能纠正胃癌术后患者的淋巴细胞免疫功能抑制,但TPN添加Arg则可促进IL2生成增加,NK细胞活性增强,改善了胃癌术后患者的淋巴细胞免疫功能,提示TPN添加Arg有免疫促进作用 相似文献
39.
食管癌术后肠外营养支持早期机体免疫功能的变化(附30例临床分析) 总被引:3,自引:0,他引:3
目的观察食管癌术后肠外营养支持早期机体免疫功能的变化。方法对30例食管癌病人根治术后,随机分为PN组和非PN组进行对比观察,分别在手术前、术后1天及术后8天检测IgG、IgA、IgM、C3、T细胞亚群、NK细胞活性和IL-2等的改变。结果食管癌病人术前均有不同程度的免疫功能低下,术后第1天,IgG、IgA、IgM、C3较术前显著下降,术后1周PN组IgG、IgA、C3恢复较快,达到或超过术前水平,与非PN组比较差异有显著意义(P<001)。CD+3、CD+4、CD+4/CD+8比值术后第1天下降明显,而PN组术后1周迅速恢复并明显超过术前水平,与非PN组相比差异有显著意义(P<001)。NK细胞活性术后第1天也明显降低,IL-2显著减少。术后1周NK细胞活性IL-2PN组较非PN组恢复较快,差异有显著意义(P<001)。结论食管癌病人术后早期免疫功能低下,应用PN包括脂肪乳剂可以有效地改善机体的免疫功能,并相应降低术后并发症和病死率。 相似文献
40.
目的研究经肠补充谷氨酰胺(Glu)对创伤大鼠免疫功能及感染后死亡率的影响。方法通过闭合性创伤模型大鼠肠内补充或不补充Glu两种方式进行对比实验。实验分为两部分:实验1测定伤后脾脏淋巴细胞及腹腔巨噬细胞的免疫功能;实验2在伤后第7天静注活绿脓杆菌,观察注菌后7天内动物的死亡率及脏器细菌检出率。结果伤后脾脏淋巴细胞增殖反应下降,IL-2生成减少,细胞膜IL-2R表达受抑;同时,腹腔巨噬细胞吞噬活性降低,IL-1产量下降。但补充Glu组的免疫抑制程度明显轻于非补充组。创伤感染后大鼠死亡率及细菌检出率补充Glu组明显低于非补充组。结论闭合性创伤大鼠免疫功能受到明显抑制,经肠补充Glu能明显改善其免疫功能,提高创伤感染后的存活率 相似文献