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991.
目的建立一种类似于PCR的蛋白质扩增方法-蛋白错误折叠循环扩增技术(PMCA),用于朊病毒病脑组织中PrPSc的检测。方法将不同浓度的羊瘙痒因子263K毒株原液与正常仓鼠脑组织匀浆混合,经反复孵育/超声,共10~15个循环。WesternBlot检测扩增产物中蛋白酶K抗性PrPSc信号。结果在本研究试验体系下,263K毒株可以利用仓鼠脑组织为基质在体外迅速复制。所建立的PrPSc-PMCA技术可检测到10-5稀释的毒株原液中的PrPSc。与常规的脑组织免疫印记方法相比,敏感度提高了105~106倍。研究还显示PrPSc还可利用小脑和脑干为基质进行体外扩增复制。结论成功建立了PrPSc-PMCA技术,为朊病毒病的早期诊断和朊病毒生物学特性的研究提供了一种新的手段。 相似文献
992.
构建7q32区域鼻咽癌和正常鼻咽上皮细胞部分基因的表达图谱 总被引:7,自引:2,他引:7
目的构建7q32区域鼻咽癌细胞和组织及原代培养人正常鼻咽上皮细胞的部分基因表达图谱。方法通过差异RT-PCR和Northern杂交的方法检测定位于7q32区域的20个EST在鼻咽癌细胞和鼻咽癌组织及原代培养人正常鼻咽上皮细胞mRNA的表达水平。结果8个EST在鼻咽癌细胞HNE1和原代培养人正常鼻咽上皮细胞中表达量较一致,7个EST在两种细胞中均无表达,3个EST(W72688、H19830、AA130630)在鼻咽癌细胞株中表达上调,而2个EST(AA070437、H90882)在原代培养人鼻咽上皮细胞中表达上调。在13例鼻咽癌活检组织中30.7%(4/13)的AA070437表达下调,77%(10/13)的W72688和77%(10/13)的H19830表达上升。结论构建了7q32区域鼻咽癌细胞和组织及原代培养人正常鼻咽上皮细胞部分基因表达图谱,并初步认为A070437的表达下调和W72688、H19830的过表达与鼻咽癌的发生有关。 相似文献
993.
Antigenic Characterization of Hantaan and Seoul Virus Nucleocapsid Proteins Expressed by Recombinant Baculovirus: Application of a Truncated Protein, Lacking an Antigenic Region Common to the Two Viruses, as a Serotyping Antigen 总被引:11,自引:1,他引:11
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Mayuko Morii Kumiko Yoshimatsu Jiro Arikawa Guizen Zhou Hiroaki Kariwa Ikuo Takashima 《Journal of clinical microbiology》1998,36(9):2514-2521
Hantaan virus (HTN) and Seoul virus (SEO) are members of the genus Hantavirus in the family Bunyaviridae and are causative agents of hemorrhagic fever with renal syndrome. The complete and truncated nucleocapsid proteins (NP) of HTN and SEO were expressed by a recombinant baculovirus system. Antigenic characterization of the NP using monoclonal antibodies (MAbs) indicated that the binding sites for the serotype-specific MAbs were located between amino acids (aa) 155 and 429. A Western blot assay indicated that the serotype-specific epitopes were conformation dependent. An indirect immunofluorescence antibody (IFA) assay with the truncated NP (aa 155 to 429) was able to distinguish convalescent-phase sera from HTN and SEO patients. However, the antibody titers with the truncated NP were lower than those with the whole NP. The truncated NP of SEO (aa 155 to 429) could be used as an enzyme-linked immunosorbent assay (ELISA) antigen, but the truncated NP from HTN lost its reactivity when used for ELISA. The IFA assay using baculovirus-expressed truncated NP as an antigen is a rapid, simple, and safe test for distinguishing between HTN and SEO infections by serotype. 相似文献
994.
β—内啡肽对大鼠免疫功能的影响 总被引:8,自引:0,他引:8
离体条件下,β-内啡肽(β-END)在10~(-6)-10~(-14)mol/L 可明显地促进ConA 诱导的脾淋巴细胞的转化及IL-2的产生,增加LPS 激活的腹腔巨噬细胞产生IL-1.纳络甯可阻断β-END 的这种作用.静脉注射β-END 也可增强大鼠脾淋巴细胞转化,促进IL-1和IL-2的产生.本结果提示,β-END 具有增强大鼠免疫功能的作用,这种作用可能是由阿片受体介导的。 相似文献
995.
ABSTRACTAvian influenza virus (AIV) can cause serious zoonotic disease, thereby threatening the poultry industry and human health. An efficient and rapid detection approach is crucial to prevent and control the spread of avian influenza. In this study, a novel protein microarray was developed. Haemagglutinin proteins of H5 and H7 subtypes and nucleoprotein (NP) were purified and spotted onto the initiator-integrated poly-(dimethylsiloxane) as antigens. Monoclonal antibodies with inhibition effect were screened and utilized for the synchronous detection of three avian influenza antibodies in different species. In the protein microarray, the cut-off values were 40%, 50% and 30% inhibition for H5 antibody detection; 50%, 50% and 20% for NP antibody detection; 40%, 50% and 40% for H7 antibody detection in chicken, peacock and duck sera, respectively. The 95 serum samples were detected by microarray, and results were compared with the findings of AIV antibody test enzyme-linked immunosorbent assay (ELISA) or haemagglutination inhibition (HI) test. NP antibody detection in the microarray showed 100% (55/55) agreement ratio in chicken using ELISA. Compared with HI, H5 antibody detection in the microarray showed 100% (95/95) agreement ratio in chicken, peacock and duck, whilst those of H7 displayed 98.18% (54/55) agreement in chicken, 100% (20/20) in peacock and 90% (18/20) in duck. In conclusion, this novel protein microarray is a high-throughput and specific method for the detection of AIV antibodies and simultaneous distinction of antibodies against H5 and H7 subtypes. It can be applied to the serological diagnosis and epidemiological investigation of AIV.RESEARCH HIGHLIGHTS
A novel protein microarray method has been developed.
The microarray can detect AIV antibodies and distinguish between H5 and H7 subtypes.
The study lays the foundation for simultaneous identification of multiple pathogens.
996.
Immune monitoring in whole blood using real-time PCR 总被引:7,自引:0,他引:7
Stordeur P Zhou L Byl B Brohet F Burny W de Groote D van der Poll T Goldman M 《Journal of immunological methods》2003,276(1-2):69-77
997.
998.
The biologically active substance P (SP) N-terminal metabolite SP1–7 has been reported to modulate several neural processes such as learning, locomotor activity and reaction to opioid withdrawal. Although all these processes are believed to be associated with dopaminergic transmission no evidence of an interaction between SP1–7 and dopamine in the case of morphine withdrawal has so far been reported. Therefore, in this work we applied in vivo microdialysis to investigate the effect of SP1–7 injection into the ventral tegmental area on dopamine release in nucleus accumbens of male rats during naloxone precipitated morphine withdrawal. The result showed that the heptapeptide enhances dopamine release and also elevates the level of the dopamine metabolite dihydroxyphenylacetic acid in this brain area. It was suggested that the observed action of the SP fragment on the dopamine system represents the underlying mechanism for a previously observed ability of SP1–7 to counteract the aversion response to morphine withdrawal. 相似文献
999.
Rutschmann S Jung AC Zhou R Silverman N Hoffmann JA Ferrandon D 《Nature immunology》2000,1(4):342-347
We have generated, by ethylmethane sulfonate mutagenesis, loss-of-function mutants in the Drosophila homolog of the mammalian I-kappa B kinase (IKK) complex component IKK gamma (also called NEMO). Our data show that Drosophila IKK gamma is required for the Relish-dependent immune induction of the genes encoding antibacterial peptides and for resistance to infections by Escherichia coli. However, it is not required for the Toll-DIF-dependent antifungal host defense. The results indicate distinct control mechanisms of the Rel-like transactivators DIF and Relish in the Drosophila innate immune response and show that Drosophila Toll does not signal through a IKK gamma-dependent signaling complex. Thus, in contrast to the vertebrate inflammatory response, IKK gamma is required for the activation of only one immune signaling pathway in Drosophila. 相似文献
1000.
T细胞性淋巴瘤组织CD56的检测及其与EB病毒的关系 总被引:3,自引:1,他引:3
目的探讨T细胞性淋巴瘤(TCL)中CD56的表达情况及CD56阳性表达同爱波斯坦-巴尔病毒(EpsteinBarVirus,EBV)感染的关系。方法对46例TCL进行CD56的免疫组织化学LSAB法检测及EBERs的原位杂交检测。结果(1)46例TCL中8例CD56阳性(17.4%),其中鼻腔、咽部和口腔阳性率最高(5/17例,29.4%)。弥漫性大细胞型淋巴瘤CD56阳性率最高(6/16例,37.5%)。(2)46例TCL中24例EBERs阳性(52.2%)。(3)8例CD56阳性病例中,4例EBERs阳性。结论CD56的表达同TCL发生部位和类型有一定关系。CD56阳性表达与EB病毒感染未发现相关性 相似文献