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41.
目的为获得日本血吸虫(Schistosoma japonicura,Sj)转化生长因子β1(TGF—β1)基因的部分或全长cDNA序列。同时验证用针对某一蛋白的抗体筛选表达文库是否可以得到相应蛋白对应的基因序列。方法采用兔抗鼠TGF—β1血清,对Sj尾蚴cDNA表达文库进行免疫学筛选,对阳性克隆进行PCR扩增后,将大于500bp的克隆进行复筛,对复筛阳性的克隆进行测序和生物信息学鉴定。结果对大约10^6个噬菌斑进行了初筛。共获得7个阳性克隆;经过PCR扩增后,其中有4个克隆大于500bp,复筛获得3个持续阳性克隆;对测序后的阳性克隆进行生物信息学鉴定,得到的三个克隆均与日本血吸虫辅酶Q10氧化还原酶(SjCHGC)基因具有高的同源性(Bhata分值都大于200)。结论SjCHGC蛋白与兔抗鼠TGF—β1抗体的反应为交叉反应,用抗某一蛋白的抗体筛选表达文库得到相应蛋白的基因序列的方法不一定可行。  相似文献   
42.
Summary Neurological complications are a major cause of morbidity and mortality in patients with disseminated malignant melanoma. We have studied and correlated clinical and cerebrospinal fluid (CSF) findings in 20 patients with central nervous system metastases from malignant melanoma including 8 patients with metastatic meningeal melanomatosis (MMM) and 12 patients with solid cerebral metastases (SCM). The putative CSF tumor markers, fibronectin and 2-microglobulin, were elevated significantly in MMM but not in SCM patients. A prominent increase in the IgM index, which reflects intrathecal B-cell stimulation, and a rise of IgG index, interleukin-6, and tumor necrosis factor- in MMM patients provide preliminary evidence for a local intrathecal immune response triggered by melanoma cell invasion of the subarachnoid space.  相似文献   
43.
本文ELLSA检测,对55例HBV感染者血清中的抗-HBcIgM随访研究其动态变化。结果发现,急性乙肝35例抗-HBcIgM的阳性率在入院时,6个月,12个月分别为100%(35/35),86%(31/36),及34%(6/18),提示抗-HBcIgM在6个月大都保持阳性,至12个月大部分消失;“无症状”携带者20例抗-HBcIgM阳性率在首检时,6个月,24个月都为100%(各为20/20,17/17,及10/10),提示“无症状”携带者的抗-HBcIgM很难自然消失,同时把抗-HBcIgM和HBsAg检测对比,提示HBsAg阴性不能排除急性乙肝的诊断。  相似文献   
44.
【目的】研究 p5 3、p2 1和bcl 2基因蛋白在舌鳞状细胞癌组织中的表达及其临床意义。【方法】用免疫组化SP法检测 5 4例舌鳞状细胞癌组织标本p5 3、p2 1和bcl 2癌基因蛋白表达。【结果】舌鳞状细胞癌组织中p5 3、p2 1和bcl 2蛋白阳性率分别为 46 %、6 1%、46 % ;p5 3和 p2 1蛋白表达与肿瘤细胞分化程度及颈淋巴结转移有关 (P <0 0 5 ) ;p5 3蛋白表达与 p2 1蛋白表达有关 (P <0 0 5 ) ,bcl 2基因蛋白表达与 p5 3或p2 1基因蛋白表达无关 (P >0 0 5 )。【结论】舌鳞状细胞癌组织中具有较高的 p5 3、p2 1和bcl 2癌基因蛋白表达 ;p5 3和 /或p2 1蛋白阳性病例恶性程度高 ,易发生颈淋巴结转移。p5 3和 /或 p2 1蛋白可作为舌鳞癌预后的参考指标  相似文献   
45.
Oncogene SET Domain Bifurcated 1 (SETDB1)/ESET, an H3K9 methyltransferase, was originally discovered over two decades ago; however, its function in the immune response was not first reported until 2011. SETDB1 immune functions include B cell maturation, T cell activity regulation, and immune escape in cancer cells. In B lymphocytes, SETDB1 mediates the transition from pro-B to pre-B cells and represses endogenous retroviruses (ERV) to encourage B cell lineage differentiation and maturation. SETDB1 alters T cell function by methylating IL-2 and IL-17 promoters and mediating T cell lineage commitment and development. In addition, SETDB1 plays a critical role in ERV silencing within a variety of immune cells, which can indirectly weaken the immune response. Although SETDB1 is critical for normal immune cell function, overexpression in cancer cells negatively impacts immune cell fights against cancer through decreased tumour immunogenicity. Within cancer cells, SETDB1 overexpression represses production and infiltration of antitumour immune cells, mediates immune escape through TE and ERV silencing, represses the type I interferon pathway, and interferes in immune checkpoint blockade (ICB) outcomes by regulation of PD-L1 expression and IFN signalling. In this review, we further discuss the immunological mechanisms of SETDB1 in normal and cancerous cells and its implications in cancer immunotherapy.  相似文献   
46.
Prolonged clinico-immunological observation of 85 patients with definite multiple sclerosis (MS) was performed in order to elucidate the connections between the clinical and immune state. A battery of immunological investigations was performed, including estimation of T-cell subpopulations in blood and cerebrospinal fluid (CSF); proliferative responses of circulating lymphocytes to mitogens, recombinant interleukin-2 (rIL2) and myelin basic protein levels in different culture conditions; levels of immunoglobulin (Ig) in sera and CSF, and of Ig production in vitro; indices of IL2 synthesis and IL2 sensitivity; production of prostaglandin E2 and tumour necrosis factor (TNF) alpha by monocytes and levels of -endorphin in sera and supernatants phytohaemagglutinin of (PHA)-activated cells. Clinical observation was performed periodically using Kurtzke scales and was supplemented by repeated recording of evoked potentials and magnetic resonance imaging. Initial investigations showed specific differences between patients with MS and the control groups (donors and patients with other neurological disorders of the same age). Correlative and regressive analyses showed no association between immunological and clinical parameters at the initial investigation, although immunological indexes were inter-related, and indicated specific alterations in immuno-regulation in MS. Retrospective analysis revealed associations between the clinical status of patients with MS and their previous immune status. Evidence of cell activation — including a decreased percentage of circulating cells with differential antigens, lower cell mitogen-induced proliferative responses in vitro, with restoration following the addition of autoserum, greater IL2 sensitivity, and increased TNF-alpha production by macrophages — often predicted the clinical manifestation of deterioration. It is proposed that the immunopathological process in MS has a number of stages with characteristic features, and that progression from one stage to another can be subclinical. No single immunological index can be used to determine stage. Only systemic alterations reflect the real situation, whilst every patient has some abnormalities. A system of clinico-immunological monitoring could severe as the basis for a new approach to the dynamic treatment of MS.  相似文献   
47.
肾综合征出血热疫苗效果免疫(感染)增强和免疫策略研究   总被引:1,自引:0,他引:1  
目的:研究肾综合征出血热疫苗效果免疫(感染)增强和免疫策略。方法:在疫苗试区设立对照组和接种组,观察期为1995年8月至1998年12月,全程接种3针,1年后加强1针。结果:全程接种了10178人,对照人群全程观察16159人,当年发病减少数为33例,4年平均保护率达93.89%。人群接种后局部和全身反应较明显。全程接种后2周荧光(IFA)抗体和中和抗体阳转率分别为100%和44.44%,一年后分别下降到28.57%和14.80%;加强后2周IFA抗体和中和抗体阳转率分别反弹至83.33%和55.56%,其抗体几何平均滴度(GMT)也随之下降和回升。结论:疫苗是安全有效的,有较好的血清学效果和流行病学效果,有免疫增强反应,但未发现感染增强反应。此外,加强免疫很有必要。  相似文献   
48.
目的 探讨人类白细胞抗原B27亚型基因与急性前葡萄膜炎(acute anterior uveitis,AAU)易感性的关系。 方法 对49例临床确诊的AAU患者,通过聚合酶链反应(polymerase chain reaction, PCR)特异性扩增技术检测B27;以B27阳性者的DNA为模板对其人类白细胞抗原HLA-B的第二、三外显子片段扩增。采用DNA测序技术对扩增产物做基因序列分析,经计算机处理获得受检者HLA-B27亚型的信息。 结果 受检者中29例为B27阳性,占59.39%,其中仅发现B2704(13例,占44.00%)和B27052(16例,占56.00%)二种亚型基因携带者。二者间多数临床表现差异不大,但携带B27052基因的AAU患者伴发强直性脊柱炎(ankylosing spondylitis, AS)的人数(7人,占24.24%)显著高于B2704基因携带者(1人,占3.74%)。 结论 B2704和B27052单独的亚型特异性与AAU无易感性关联;但B27052基因可能与并发AS有关。 (中华眼底病杂志, 1999, 15:139-142)  相似文献   
49.
Summary The immunogenicity of a virus-induced rat osteosarcoma was studied utilizing the lymphocyte microcytoxicity test. Lymphocytes from progressor animals (in which the tumour progressed and metastasized) demonstrated an ability to kill osteosarcoma cells in vitro, while serum from these animals abrogated or blocked the cell-mediated cytotoxicity.Lymphocytes from regressor animals (in which tumours failed to develop or regressed spontaneously) also showed cytolytic activity against osteosarcoma cells in vitro, but their serum failed to block the lymphocyte-mediated cytolysis. Both progressor and regressor animals demonstrated the presence of humoral cytotoxic antibodies to tumour antigens on the basis of the ability of their serum to kill tumour cells in vitro. In an attempt to alter the fatal course of the disease in progressor animals, immunoprophylaxis and immunotherapy of the osteosarcoma in F1 hybrid rats war carried out by injecting them with parentalor, third party, allogeneic lymphoid cells. Injection of parental spleen lymphocytes into F1 hybrids produced a transient graft versus host reaction (GVHR), and prolonged the survival of the animals when lymphocytes were injected three days before, seven days after and on the day of tumour induction. Injection of allogeneic, third party lymphoid cells produced no detectable GVHR and prolonged the survival of F1 hybrids with osteosarcoma only when injected on the day of tumour induction. The prolonged survival of the groups treated with parental lymphoid cells was a result of stimulation of the host's immunological mechanisms during a transient GVHR, whereas the prolongation of survival in the group given allogeneic cells was most likely the result of a direct action of the donor lymphocytes on tumour cells, and not connected to a GVHR.SICOT Fellowship Award Paper, presented at the XIV-th World Congress of SICOT, Kyoto, Japan, October 15–20, 1978  相似文献   
50.
Summary This study describes a sensitive enzyme-linked immunosorbent assay (ELISA) using rabbit anti-bovine S1-casein antibody for the detection of commercial milk and milk-containing vomit. The antibody does not react with other human body fluids such as breast milk. The stability of S1-casein antigenic activity was examined after storage at different temperatures and enzyme digestion. There was no decrease after storage for one year at room temperature but 40% of the activity was lost after 6 months at 37°C. Enzyme digestion (6 hours, 37°C) resulted in 65 70% loss of activity but the antibody reacted with the peptide fragments of S1-casein. Vomit samples from 3 normal infants were tested by ELISA, and a S 1-casein could be detected in 1 cm2 stain.  相似文献   
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