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31.
目的探讨血清IL10、IL18在肝炎肝硬化的发病机制中的作用。方法62例肝炎肝硬化患者根据childpugh分级法分为3组:childpughA级组19例、childpughB级组23例和childpughC级组20例。采用ELISA法检测3组患者和20例健康献血员血清IL10、IL18的水平。结果childpughA、B、C级组血清IL18水平均明显高于对照组(P均<0.01),childpughA级组血清IL10水平略高于对照组,但无显著性差异(P>0.05);childpughB、C级组明显低于对照组(P<0.05);有腹水组、无腹水组血清IL18水平均明显高于对照组(P均<0.01),有腹水组血清IL10水平明显低于无腹水组、对照组(P<0.05,P<0.01);血清IL10水平与血清IL8水平呈负相关(r=-0.51,P<0.01);血清白蛋白水平与血清IL10水平呈正相关(r=0.566,P<0.01),与血清IL8水平呈负相关(r=-0.315,P<0.01);血清凝血酶原活动度与血清IL10水平呈正相关(r=0.506,P<0.01),与血清IL18水平呈负相关(r=-0.463,P<0.01);血清总胆红素水平与血清IL8水平呈正相关(r=0.677,P<0.01),与血清IL10水平呈负相关(r=-0.339,P<0.01)。结论IL10、IL18在肝炎肝硬化的发病机制中起一定的作用,其水平与肝损害程度密切相关。  相似文献   
32.
SJL/J mice challenged with myelin basic protein (MBP) in complete Freund's adjuvant (CFA) developed only mild chronic-relapsing experimental allergic encephalomyelitis (EAE) with very low incidence. However, treatment of challenged mice with anti-infeferonγ (IFN-γ) monoclonal antibody (mAb) determined severe disease in all cases. Similarly, in passive EAE, the addition of anti-IFN-γ to the in vitro MBP-activated cells at the time of transfer led to significant disease exacerbation in all recipients. The disease enhancing effect was observed only when the mAb was given at the time of active challenge or of passive transfer, but not at later times. Anti-interleukin-2 (IL-2) antibody had only a marginal effect in the active induction, but drastically reduced the manifestations of passive EAE, even when mixed with a disease-enhancing dose of anti-IFN-γ. These findings support the notion that IL-2 is required for disease induction whereas IFN-γ plays a disease-limiting role early in the development of EAE.  相似文献   
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34.
肿瘤微环境对树突细胞功能状态的影响   总被引:2,自引:0,他引:2  
目的:探讨肿瘤细胞分泌的可溶性细胞因子营造的微环境对树突细胞(DCs,dendritic cells)的分化发育的影响,以进一步揭示肿瘤的免疫逃逸机制。方法:用免疫磁珠从人外周血分离CD14^ 单核细胞,加入粒细胞巨噬细胞集落刺激因子(GM-CSF)、白细胞介素4(IL-4)和人白血病细胞Jurkat培养上清液体外培养DCs,以正常培养诱导的DCs作为对照,采用傅立叶变换红外光谱(FTIR)技术分析人白血病细胞培养上清液对DCs分化发育的影响。结果:正常培养DCs与肿瘤上清液培养的DCs相比,在细胞内蛋白质和核酸的相对含量和细胞内消耗葡萄糖重新合成磷脂的量方面差异无显著性,但是,在细胞的转录状态方面差异有显著性。结论:肿瘤细胞上清液培养液所营造的微环境细胞转录水平上对DCs的功能状态有明显的抑制作用。  相似文献   
35.
Summary In order to study the immune function of patients on maintenance hemodialysis (MHD), we assayed NK cell cytotoxicity against K562 targets in 40 patients on MHD, and the production of IL-2 and IFN in peripheral blood mononuclear cells (PBMC) after PHA stimulation, in contrast to those in normal controls. The results showed that NK cell activity and IL-2 and IFN levels were markedly lower in the patients than in the controls. Afeter a single dialysis, NK cell activity as well as IL-2 and IFN levels were elevated to different extent. But there was no significant change in patients after long-term dialysis. There was a positive correlation between the NK cell activity and IL-2 and IFN activity in the controls, but no such correlation was found in the patients on MHD. There was a positive correlation between the NK cell activity and IL-2 activity in patients after dialysis, suggesting that immune function were impaired in the patients on MHD, with a decline in the activity of NK cell and IL-2 and IFN, and a disorder of immune regulation cycle. These abnormal immune impairments in the patients could be partly corrected by hemodialysis. However, long-term hemodialysis is not much helpful in the improvement of patient’s immune function.  相似文献   
36.
Summary. Interleukin (IL)-12 is a pleiotropic cytokine produced by antigen-presenting cells in response to diverse stimuli. IL-12 is a key molecule in the regulation of host's immune responses. In particular, IL-12 influences the balance between the T-helper cells type 1 (TH1) and type 2 (TH2); it modulates macrophage responses through the control of interferon-gamma synthesis by TH1 cells; and, suppresses IgE class antibody production (has a suppressive effect on allergic reactions) and promotes a shift in the IgG subclasses. IL-12 enhances resistance to several infectious diseases, is a powerful antitumor agent in vivo , and acts as a vaccine adjuvant. The biological properties of IL-12 point to the potential therapeutic use in persistent hepatitis B virus and hepatitis C virus infection.  相似文献   
37.
Interleukin-5 has a specific role in various eosinophilic activities. It is the predominant cytokine produces by activated T-lymphocytes isolated from patients with idiopathic hypereosinophilic syndrome. We studied a young patient suffering from idiopathic hypereosinophilic syndrome who presented with Horner's syndrome, peripheral neuropathy and skin ulcers. The IL-5 gene expression by CD4+ T-lymphocytes and the peripheral eosinophil count were raised. The skin ulcers continued to deteriorate despite a swift reduction of the IL-5 gene expression and peripheral eosinophil count following systemic corticosteroid treatment. We suggest that peripheral eosinophilia may not be responsible for the damage in skin lesions and more aggressive treatment may be required.  相似文献   
38.
目的:通过大鼠坐骨神经慢性挤压伤(CCI)神经性疼痛模型的热敏变化及血清中IL-6含量的变化,探讨血清IL-6在神经性疼痛形成中的作用及可能机制.方法:36只250~300g的健康雄性Wistar大鼠,在戊巴比妥钠麻醉下于大腿中部暴露坐骨神经并作结扎,取对侧大腿坐骨神经暴露作为模拟对照(B组).术后1,3,5,7,9,11,13,15 d测定大鼠(n=12)两侧后爪对热敏阈值的变化.于术后第15 d处死大鼠,取血清,ELISA法测定IL-6浓度.结果:大鼠双侧后爪(CCI和B)的收缩潜伏期在术后第3,5,7,9,11,13,15 d有显著差异;CCI组血清IL-6与对照组比较有显著差异.结论:IL-6与大鼠坐骨神经慢性挤压性损伤后出现的神经源性疼痛过敏有关.  相似文献   
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40.
In patients with allergic asthma and rhinitis high numbers of hypodense eosinophils (HE) have been demonstrated. In a previous study we reported that asthmatic and healthy children had more HE than their adult counterparts. We assumed that this might, in part, he due to the presence of immature eosinophils in children. To distinguish between immature and activated eosinophils, determination of eosinophil cationic protein (ECP) might be interesting as it is known that high serum levels of ECP are associated with increased activation of eosinophiis. In this study we determined (he levels of ECP in scrum in asthmatic and healthy children and adults trying to distinguish activated from immature eosinophils. We found that ECP levels were not increased in children (healthy and asthmatic) compared to adults (healthy and asthmatic). This supports the hypothesis that increased numbers of HE in childhood are, at least in part, immature eosinophils. Nevertheless, we could confirm that inflammation was present in children because soluble interleukin-2-receptor (slL-2R), a marker of lymphocyte activation, was higher in asthmatic children as compared to healthy children. IL-6, a marker of macrophage/monocyte activation, was not different in the different patient groups. We conclude that although signs of inflammation are present in childhood asthma, the increased numbers of HE in children are in part due to the presence of immature eosinophils.  相似文献   
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