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61.
The Association of Directors of Anatomic and Surgical Pathology has developed recommendations for the surgical pathology report for common malignant tumors. The recommendations for tumors of the adrenal cortex and medulla are reported herein. Received: 30 March 1999 / Accepted: 30 March 1999  相似文献   
62.
We investigated the effects of a single bacterial lipopolysaccharide (LPS) injection in vivo on the gene expression of tumor necrosis factor-α (TNF) and its receptors: TNF receptor type I (TNF-R 55 kDa or TNF-R1) and TNF receptor type II (TNF-R 75 kDa or TNF-R2) in various tissues and white blood cells. While TNF mRNA rapidly accumulated in most tissues, TNF-R1 and TNF-R2 mRNA levels were found to be differentially regulated in lung, spleen, lymph nodes and white blood cells. In most cases, TNF-R mRNA levels did not parallel TNF mRNA levels. These observations indicate that TNF-R of both types are capable of modulating the host response to LPS, not only by shedding of their extracellular domains, but also by strict regulation of their gene expression.  相似文献   
63.
本文报道了30例食管癌、20例胃癌、15例乳腺癌、8例肝癌、10例淋巴瘤等患者红细胞免疫粘附功能的初步结果,并与67例献血员值进行了比较。几种肿瘤病人的RBC C_(3b)RR低下,RBC-ICR较高,两者与献血员值比较都有明显差别(P<0.01),几种肿瘤患者CIC阳性率在60~83.4%之间。对食管癌患者部分病例进行跟踪检测,并对其临床意义进行了初步探讨。  相似文献   
64.
Adaptive immune surveillance by T cells against infections and tumors depends on the presence of antigenic peptides presented by major histocompatibility complex (MHC) molecules. If antigenic tumor-specific peptides or MHC class I molecules are absent, the adaptive T cell immune response fails. Natural killer (NK) cells seem to complement the specific T cells by recognizing target cells lacking MHC class I (e.g. RMA-S). The role of perforin, which is crucially involved in T cell and NK cell-mediated target cell lysis, was evaluated in mice lacking perforin with respect to their capacity to eliminate a syngeneic lymphoid tumor. Here, we show that growth of MHC class I? RMA-S tumor cells in unprimed mice was controlled by NK cells through perforin-dependent cytotoxicity.  相似文献   
65.
Sputum cytology was performed in 179 cases of squamous-cell carcinoma of the lung; 134 cases were diagnosed as positive. There were no significant differences in diagnostic accuracy of sputum cytology between tumors sizes. In cases with tumors extending proximally into the main, lobar, or segmental bronchi, the diagnostic accuracy of sputum cytology was significantly higher than in cases where the proximal invasion of tumor was limited to the peripheral bronchi. In cases with tumors 3 cm or less in diameter, when tumors extended proximally into main, lobar, or segmental bronchi, the diagnostic accuracy of sputum cytology was significantly higher than in cases with tumors extending proximally into subsegmental or subsubsegmental bronchi. In peripherally located squamous-cell carcinoma, in cases in which the tumor arose in subsegmental or subsubsegmental bronchi, carcinoma could be detected by sputum cytology even when it was roentgenographically occult.  相似文献   
66.
Tumor necrosis factor (TNF) activity was inhibited during the development of actively-induced, chronic relapsing experimental allergic encephalomyelitis (CREAE) in Biozzi AB/H mice, using a mouse TNF-specific (TN3.19.12) antibody and bivalent human p55 and p75 TNF receptor-immunoglobulin (TNFR-Ig) fusion proteins. The development of disease could be inhibited when repeated doses of antibody were administered prior to the anticipated onset. It has now also been shown that a therapeutic effect is evident even when antibody is administered after the onset of clinical signs, further indicating an important role for TNF in pathogenic effector mechanisms in CREAE. Although biologically-active TNF was not detected in the circulation, TNF-α was detected in lesions within the central nervous system (CNS). This suggested that the CNS may be the main site for TNF-specific immunomodulation and was supported by the observation that intracranial injection was significantly more potent than that administered systemically, for both antibody and TNFR-Ig fusion proteins. The fusion proteins were as effective as antibody at doses 10—100-fold lower than that used for antibody, reflecting their higher neutralizing capacity in vitro. Although treatment was not curative and relapse inevitably occurred in this model if treatment was not sustained, the data indicate that anti-TNF immunotherapy, especially within the CNS, can inhibit CREAE and may, therefore, be useful in the control of human neuroimmunological diseases.  相似文献   
67.
我们利用兔抗微管蛋白抗体和兔抗辣根过氧化物酶(HRP)抗血清制备的HRP—抗HRP(PAP)复合物,建立了微管的PAP免疫酶细胞化学方法。应用此法观察到人食管癌ECa 109、胃癌SGC 7901,乳腺癌MCF 7和成骨肉瘤OS 732细胞间期胞质微管减少或消失,只有大量弥散分布的微管蛋白棕色反应产物,在微管组织中心(MTOC)附近十分密集,而正常成纤维细胞和胎儿胃粘膜上皮细胞间期,都有发达的胞质微管结构(CMTC)。在分裂期,这些肿瘤细胞都显示纺锤体微管,与正常细胞比较无明显差异。本研究应用PAP方法进一步证明,以前用免疫荧光细胞化学方法观察到的人肿瘤细胞间期胞质微管缺陷的特征。除去低温(4℃)或秋水仙酰胺处理后,解聚的CMTC又可恢复,表明本方法与免疫荧光染色法,同样具有很高的特异性。本工作在细胞固定及免疫反应的某些步骤上有所改进。  相似文献   
68.
Accumulating evidence indicates that tumor viruses represent a major etiological factor in a significant portion of human cancers. These cancers include human papillomavirus induced anogenital cancers, hepatitis B and C virus associated hepatocellular carcinomas, nasopharyngeal carcinomas and lymphomas linked to Epstein-Barr virus infection, and human T cell leukemia virus associated adult T cell leukemias. This review summarizes the recent progress made in understanding the molecular mechanisms of viral carcinogenesis, with a particular focus on the interaction of viral factors with cellular tumor suppressor proteins. The functional inactivation of tumor suppressor proteins may represent a common strategy by which several tumor viruses contribute to malignant cell transformation.Abbreviations EBV Epstein-Barr virus - E6AP E6-associated protein - HBV Hepatitis B virus - HCC Hepatocellular carcinoma - HPV Human papillomavirus - HTLV Human T cell leukemia virus - pRb Retinoblastoma protein - RB Retinoblastoma - SV40 Simian virus 40  相似文献   
69.
本研究测定与肿瘤关系密切的微量元素Zn、Cu、Mn、Cr和Se在口腔颌面部正常者与良、恶性肿瘤患者血清中含量共91例。结果表明微量元素Zn、Cu、Mn、Cr和Se在口腔颌面部肿瘤与其它部位肿瘤一样有明显变化。用模式识别方法以微量元素作为指标,对良恶性肿瘤进行鉴别诊断,有一定的临床意义。  相似文献   
70.
病毒性肝炎患者IL-1、IL-6和TNFα活性的检测   总被引:4,自引:0,他引:4  
检测了甲、乙型病毒性肝炎患者外周血单个核细胞(PBMCs)IL-1、IL-6和TNFα的诱生活性及其血清中活性。结果表明,乙型慢性活动性肝炎(CAH)、乙型肝炎后肝硬化(HC)和乙型重型肝炎(SH)PBMCs经脂多糖诱导后,IL-1活性分别为3531.1±882.7U/m1、2769.7±730.4±U/ml和5329.3±1089.3U/ml,高于正常对照组(P<0.05或(0.01);IL-6诱生活性分别为38.90±14.75U/m1、2.45±18.85U/ml和71.95±28.05U/ml(与正常对照组相比,p<0.05或<0.01);TNFα诱生活性在乙型慢性迁延性肝炎(CPH)、CAH、HC和SH中分别为33.23±7.25U/ml、6.99±1.84U/m1、4.29±2.17U/ml和86.70±24.18U/ml,与对照组相比P<0.05或P<0.01。各型患者血清中IL-1、IL-6和TNFα活性均有不同程度的增高。文中对SH患者IL-1、IL-6和TNFα之间的相互关系进行了探讨。  相似文献   
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