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91.
To investigate how the immune system responds to tumor self antigens, we used enhanced green fluorescent protein (EGFP) in B16 melanoma cells (B16-EGFP) and tested in the mouse lines expressing EGFP in thymic epithelial cells (3.1T-EGFP) or in antigen presenting cells (Get40), in comparison to the wild-type mouse. B16-EGFP cells were distinctively immunoedited in three mouse lines at the early phase, and the cells were completely eliminated only in the wild-type at the late phase, suggesting EGFP-specific tolerance is present in 3.1T-EGFP and Get40. The numbers of tumor-infiltrating T cells in all mouse lines were reversely correlated with the tumor sizes, suggesting dominant T cell mediated tumor elimination. When a soluble EGFP was immunized, surprisingly, the growth of B16-EGFP in Get40 mouse was promoted, while reduced in B6. Immunization did not make significant difference in the growth of tumors in 3.1T-EGFP. Detailed analyses showed the opposite directional changes in the numbers of B and CD8+T cells in B6 and Get40. In Get40 mice, the immunization significantly reduced the percentage of Gr1?CD11b+ cells, indicating that tolerance induction and breaking involve both adaptive and innate cells differentially. Therefore, the strategy for a cancer vaccine should be carefully considered on the types of antigen expressing cell.  相似文献   
92.
Genitourinary cancers comprise of a heterogenous group of cancers of which renal cell carcinoma, urothelial bladder carcinoma, and prostate adenocarcinoma are the most commonly encountered subtypes. A lot of research is ongoing using various strategies for exploration of novel biomarkers for genitourinary cancers. These biomarkers would not reduce the need for invasive diagnostic techniques but also could be used for early and accurate diagnosis to improve the clinical management required for the disease. Moreover, selecting the appropriate treatment regimen for the responsive patients based on these biomarkers would reduce the treatment toxicity as well as cost. Biomarkers identified using various advanced techniques like next generation sequencing and proteomics, which have been classified as immunological biomarkers, tissue-specific biomarkers and liquid biomarkers. Immunological biomarkers include markers of immunological pathways such as CTLA4, PD-1/PDl-1, tissue biomarkers include tissue specific molecules such as PSA antigen and liquid biomarkers include biomarkers detectable in urine, circulating cells etc.The purpose of this review is to provide a brief introduction to the most prevalent genitourinary malignancies, including bladder, kidney, and prostate cancers along with a major focus on the novel diagnostic biomarkers and the importance of targeting them prior to genitourinary cancers treatment. Understanding these biomarkers and their potential in diagnosis of genitourinary cancer would not help in early and accurate diagnosis as mentioned above but may also lead towards a personalized approach for better diagnosis, prognosis and specified treatment approach for an individual.  相似文献   
93.
Adaptive immunity is regulated by dynamic interactions between T cells and antigen presenting cells (''APCs'') referred to as ''immunological synapses''. Within these intimate cell-cell interfaces discrete sub-cellular clusters of MHC/Ag-TCR, F-actin, adhesion and signaling molecules form and remodel rapidly. These dynamics are thought to be critical determinants of both the efficiency and quality of the immune responses that develop and therefore of protective versus pathologic immunity. Current understanding of immunological synapses with physiologic APCs is limited by the inadequacy of the obtainable imaging resolution. Though artificial substrate models (e.g., planar lipid bilayers) offer excellent resolution and have been extremely valuable tools, they are inherently non-physiologic and oversimplified. Vascular and lymphatic endothelial cells have emerged as an important peripheral tissue (or stromal) compartment of ''semi-professional APCs''. These APCs (which express most of the molecular machinery of professional APCs) have the unique feature of forming virtually planar cell surface and are readily transfectable (e.g., with fluorescent protein reporters). Herein a basic approach to implement endothelial cells as a novel and physiologic ''planar cellular APC model'' for improved imaging and interrogation of fundamental antigenic signaling processes will be described.  相似文献   
94.
胰岛移植已经被公认为治疗胰岛素依赖型糖尿病(IMDD)的有效手段,而现如今胰岛移植的最大障碍是移植排斥反应。目前控制胰岛移植的免疫抑制治疗因其对胰岛细胞的毒性作用及长期应用带来的全身并发症而无法在临床推广,诱导移植术后受体的免疫耐受是防止排斥反应的最理想方法。本文综述了诱导免疫耐受的途径及胰岛移植的最新实验进展。随着研究的深入和免疫学的发展,相信在未来的胰岛移植治疗糖尿病领域,移植排斥现象将能得到高效可靠的解决。  相似文献   
95.
Epitope-based vaccines provide a new strategy for prophylactic and therapeutic application of pathogen-specific immunity. A critical requirement of this strategy is the identification and selection of T-cell epitopes that act as vaccine targets. This study describes current methodologies for the selection process, with dengue virus as a model system. A combination of publicly available bioinformatics algorithms and computational tools are used to screen and select antigen sequences as potential T-cell epitopes of supertype human leukocyte antigen (HLA) alleles. The selected sequences are tested for biological function by their activation of T-cells of HLA transgenic mice and of pathogen infected subjects. This approach provides an experimental basis for the design of pathogen specific, T-cell epitope-based vaccines that are targeted to majority of the genetic variants of the pathogen, and are effective for a broad range of differences in human leukocyte antigens among the global human population.  相似文献   
96.
利用PCR技术,从A型产气荚膜梭菌标准株染色体DNA中扩增出α毒素基因,构建了含α毒素基因的重组菌株BL21(DE3)(pXETA02)。经酶切鉴定和序列测定证实,构建的表达质粒pXETA02含有α毒素基因序列。经SDS-PAGE、Western blot分析和ELISA检测,重组菌株表达的α毒素蛋白能够被α毒素单抗识别。表达优化结果表明,以IPTG为诱导剂诱导α毒素表达的优化条件是:培养基pH 7.5,培养温度37℃,IPTG浓度0.8mmol/L,菌体生长密度OD600达到0.8时加入IPTG,诱导时间5h,此时α毒素蛋白表达量为34.83%。以乳糖为诱导剂诱导α毒素表达的优化条件是:培养基pH7.5、培养温度37℃,乳糖浓度0.1g/L,菌体生长密度OD600达到0.8时加入乳糖,诱导时间5h,α毒素蛋白表达量为23.82%。动物实验结果表明,用重组菌株α毒素蛋白免疫的小鼠可以抵抗1MLD的A型产气荚膜梭菌标准株C57-1毒素攻击。  相似文献   
97.
轮状病毒(rotavirus, RV)非结构蛋白1(non structural protein 1, NSP1)在病毒与宿主的相互作用中发挥着重要的功能。运用基因克隆和表达技术在大肠杆菌中表达了TB-Chen株RV NSP1蛋白,进行了NSP1的免疫学性质和RV感染细胞中NSP1蛋白的合成与分布以及NSP1的系统进化和基因分型研究。结果表明,大肠杆菌BL21(DE3)能高效表达重组NSP1蛋白(rNSP1),rNSP1表达量约占菌体总蛋白的34.4%。rNSP1能诱导免疫豚鼠产生特异性血清抗体。Western blot及免疫荧光检测结果表明,抗rNSP1血清抗体能特异性识别自身蛋白,对SA11、Wa株的NSP1蛋白有交叉反应性;免疫荧光结果还表明,SA11感染的MA104细胞中合成的NSP1蛋白在细胞质中区域化聚集形成辐射状排列的颗粒状结构,而Wa株的NSP1不能形成此样结构。至今发现的A组RV至少可以分为16个不同的NSP1基因型,TB-Chen株NSP1为A2型。不同基因型有独特的敏感宿主范围,同一基因型可能感染不同种动物,同一种动物也可能感染不同基因型。基因型A4型和A16型仅在鸟类病毒株中出现;而且鸟类中只有A4型和A16型。研究结果为进一步研究NSP1蛋白质的结构功能及其应用开发奠定了很好的基础。  相似文献   
98.
免疫致敏结合局部乙酸刺激法建立大鼠溃疡性结肠炎模型   总被引:6,自引:1,他引:5  
目的结肠黏膜组织致敏法加乙酸局部刺激法建立复合大鼠溃疡性结肠炎模型。方法30只Wistar大鼠随机分为正常对照组、模型对照组、用药组(各10只),用结肠黏膜组织致敏法加乙酸局部刺激法建立大鼠复合溃疡性结肠炎模型后,用药组给予SASP灌胃,模型对照组和正常对照组给予生理盐水,均灌胃2周后处死大鼠,分离其结肠组织和血清。生化法检测各组结肠中MDA、SOD、GSH-PX、NO、TNOS和iNOS值,放免法测定大鼠血清及结肠IL-4及TNF-α含量变化,酶联免疫法测定大鼠血清IFN-γ含量变化。结果与空白对照组比较,模型组大鼠结肠组织MDA、NO、TNOS及iNOS含量升高,SOD、GSH-Px水平显著降低。与模型组比较,SASP组SOD、GSH-Px计数水平显著升高,组织MDA、NO、TNOS及iNOS含量降低。模型组血清和结肠IL-4含量较对照组明显降低,而模型大鼠血清和结肠TNF-α含量明显升高,模型组大鼠血清IFN-γ含量明显升高。SASP组IL-4含量升高,TNF-α和IFN-γ含量明显降低。结论改进的复合造模方法,可以较好的模拟人类UC病变的慢性活动性特点,适合药效观察和评价。  相似文献   
99.
人体是个巨大的生态系统,各个器官的表面附着大量的微生物,微生物群通过与宿主细胞之间的相互作用来保证机体的正常营养代谢和微生态稳定。长期以来由于呼吸道的生理功能和特性,其微生物菌群的调节作用没有引起足够重视。自“肠-肺轴”的提出,更多学者开始致力于研究呼吸道微生态,并发现一些呼吸道疾病如慢性阻塞性肺疾病、特发性肺纤维化以及支气管哮喘等的发生发展与呼吸道微生态存在一定的关系,这为进一步研究呼吸道疾病,并寻求更好的治疗方式提供新的方向和选择。本文就支气管哮喘与呼吸道微生态之间的作用关系作一综述。  相似文献   
100.
目的:观察大豆皂苷(soyasaponins,SS)对荷瘤小鼠免疫功能的影响。方法:建立S180荷瘤小鼠模型,随机分为模型对照组、环磷酰胺组(CTX)组(20mg/kg)、SS低、中、高剂量组(10、20、30mg/kg),每组12只。连续给药15天后处死小鼠,测量小鼠免疫器官指数、淋巴细胞转化率(采用MTT法)、溶血空斑数(采用Jeme改良玻片法)、巨噬细胞吞噬功能(采用半体内法)以及NK细胞活性(采用乳酸脱氢酶法)。结果:SS中、高剂量组提高小鼠脾脏指数、脾淋巴细胞转化率、溶血空斑数、巨噬细胞吞噬率及吞噬指数、NK细胞活性,与模型对照组比较有显著性差异(P〈0.05)。与模型对照组比较,SS各剂量组胸腺指数无明显差异(P〉0.05)。结论:一定剂量的SS具有增强荷瘤小鼠免疫功能的作用,从而发挥抗肿瘤作用。  相似文献   
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