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991.
Fas及Fas-L在乳腺浸润性导管癌及癌旁组织中的表达   总被引:2,自引:0,他引:2  
Xia C  Zhao H  Tang X 《中华外科杂志》1999,37(11):648-650
目的 探讨Fas及Fas-L与乳腺浸润性导管癌发生、发展及肿瘤分化程度的关系。方法 用免疫组织化学方法对50例乳腺浸润性导管癌及其癌旁组织的Fas-L进行检测。结果 Fas有乳腺浸润性导管癌中的表达阳性率为76%,显著低于其癌旁组织的96%(P〈0.01);Fas-L在乳腺浸润性导管癌中的表达阳性率94%,显著高于其癌旁组织的84%(P〈0.01),不同分化程度乳腺浸润性导管癌中的表达阳性率为94  相似文献   
992.
目的探讨乳腺癌组织中第Ⅷ因子相关抗原和组织蛋白酶D在其转移、预后中的关系。方法采用免疫组化SP法对33例乳腺癌进行第Ⅷ因子相关抗原(F8)和组织蛋白酶D(Cath-D)染色。结果33例乳腺癌微血管F8染色均阳性(100%)。癌组织内染色阳性在70%以上者7例(21.21%),癌周组织阳性在70%以上者25例(71.67%),两者有明显差异(P<0.01)。F8表达与腋窝淋巴结转移有相关性(P<0.01)。33例乳腺癌Cath-D阳性者30例,占90.09%。结论F8、Cath-D免疫组化染色对判断乳腺癌转移、预后有着重要意义。两项同时检测可起互补作用。  相似文献   
993.
子宫内膜异位症患者免疫功能的变化   总被引:2,自引:0,他引:2  
目的 为了探讨子宫内膜异位症发病的免疫机制。方法 采用间接免疫荧光法对子宫内膜异位症患者外周血中的 T细胞亚群、 B 细胞, N K 细胞及 I L- 2 R+ 细胞进行检测,并采用酶联免疫双抗体夹心法对子宫内膜异位症患者外周血及腹腔液中的 T N F- α浓度进行了检测。结果 子宫内膜异位症患者外周血中 T 细胞亚群失衡、 B 细胞增多,外周血及腹腔液中的 T N F- α浓度显著升高。结论 外周血中 T 细胞亚群失衡、 B 细胞增多,腹腔液中 T N Fα浓度升高可能与子宫内膜异位症的发生,发展密切相关。  相似文献   
994.
目的 探讨肿瘤可溶性抗原免疫原性,为肿瘤疫苗的研制和肿瘤免疫治疗提供实验依据。方法 提取卵巢癌细胞的可溶性成分作为肿瘤可溶性抗原(tumorsolubleantigen,TSA),单独用TSA或联合IL-2,CD-3单抗诱导外周血单个核细胞(PBMC),检测PBMC活化、增殖、分泌细胞因子以及活化的细胞对肿瘤的杀伤特性。结果 TSA能刺激正常人PBMC增殖和分泌细胞因子(TNF,IFN)。用TSA联合IL-2和抗CD3单抗诱导正常人PBMC产生杀瘤性效应细胞,对TSA来源的肿瘤细胞具有选择性杀伤作用,证实TSA具有免疫原性。肿瘤细胞提取物中细胞多肽是主要活性成分,但细胞膜成分也具有免疫活性。结论 用该实验方法提取TSA具有免疫原性,可用于肿瘤疫苗的研制和肿瘤过继免疫治疗,该实验方法和结果可为检测和评价肿瘤提取物是否具有免疫原性提供参考。  相似文献   
995.
雄性成年SD大鼠随机分为5组,分别于右侧睾丸内注射生理盐水、70%甘油和PN。7天后重复1次。第15天取样,进行精子分析、睾丸及主要副性腺测量和组织病理学观察。结果显示,睾丸内注射PN引起了性腺、副性腺萎缩,精子性状改变以及组织病理学改变。推测可能是:(1)PN或PL与PLP竞争结合部位和抑制PLP的合成,干扰细胞代谢;(2)通过转化形式或直接作用于Sertoli细胞,损害细胞骨架。(3)直接透过血睾屏障而损害管腔小室内的生精细胞  相似文献   
996.
Retinoblastoma, the most common intraocular malignancy in childhood, has served as a paradigm for the study of genetic mechanisms of oncogenesis. The retinoblastoma susceptibility gene RB1 was the first tumor suppressor gene to be cloned, and genetic and molecular biologic studies of this tumor have greatly expanded the understanding of the mechanics of tumorigenesis. Human retinoblastoma has essentially no naturally occurring animal counterpart. The development of transgenic murine models of retinoblastoma have created an experimental tool for manipulation of a tumor gene system in vivo. These models have also enabled studies of new therapeutic modalities. This review outlines the development of the transgenic murine models of retinoblastoma, together with the genetic mechanisms of retinoblastoma origin. Current therapeutic innovations developed by means of the transgenic models are described.  相似文献   
997.
肺癌患者血清一氧化氮浓度变化的观察   总被引:1,自引:0,他引:1  
于兰  陈新民 《天津医药》1999,27(10):596-597
为了解肿瘤患者体内NO变化规律,应用萘乙烯二胺盐酸盐显色法对25例健康人及18例肺癌患者者进行了血清NO含量测定,同时采用放射免疫法进行了TNF-α及SOD平行测定。结果示,肺癌患者血清NO及TNF-α含量明显高于对照组,而血清SOD含量明显低于对照组,NO含量与TNF-α及SOD含量间不存在明显相关性变化,肺癌患者血清,NO浓度随病情严重程度及病程延长而增加,与肿瘤病理分型无明显相关。  相似文献   
998.
Virtually every variant of neuroendocrine neoplasia can occur, at least rarely, in the head and neck region. This review focuses on the terminology surrounding neuroendocrine carcinomas of the larynx and their distinction from morphologically similar but biologically distinctive neoplasmas. It is suggested that rare typical laryngeal carcinoids be labeled as such. There is little evidence that these lesions are part of a morphologic continuum. In contrast, more common “carcinoid-like” carcinomas, previously referred to as “atypical carcinoids” are more appropriately labeled as “moderately differentiated neuroendocrine carcinomas”. These neoplasms should, in turn, be distinguished from “small cell neuroendocrine carcinomas,” although these latter two neoplasms do represent a morphologic and behavioral spectrum. Light microscopic and immunohistochemical features distinguishing neuroendocrine carcinomas of the larynx from paraganglioma, metastatic medullary carcinoma, malignant melanoma, and basaloid squamous cell carcinoma are presented. The second portion of this review outlines the clinicopathologic features of two head and neck neoplasms exhibiting varying degrees of neuroendocrine differentiation. Olfactory neuroblastomas have well-developed neuroendocrine differentiation, almost invariably arise from the olfactory mucosa, typically exhibit low-grade cytologic features, and may have protracted clinical course with an approximately 50% overall 5-yr survival. In contrast, sinonasal undifferentiated carcinoma is a microscopically high-grade neoplasm with minimal, abortive neuroendocrine features, a highly aggressive clinical course, and virtually 100% mortality. They can arise throughout the sinonasal region. Presented at the Endocrine Pathology Society—USCAP Meeting, Washington, DC, March 23, 1996.  相似文献   
999.
Primary spinal cord primitive neuroectodermal tumor (PNET) is a rare entity. In all, 13 cases have been reported in the literature, including 3 with intracranial seeding. A 3-month-old girl with involvement of the spinal cord below the mid-thoracic level is described. The brain MRI revealed findings indicative of seeding along the intracranial subarachnoid space. Biopsy, duraplasty and removal of laminotomy flap were done. In spite of a good response to the first cycle of postoperative 8-drugs-in-a-day chemotherapy, further treatment was refused. She died 21 days after the onset of leg weakness, which reveals the rapid progression of untreated cases. To our knowledge, this is the first case of spinal cord PNET with parenchymal involvement that has been described in an infant.  相似文献   
1000.
Summary The growth inhibitory effect of IFN- was evaluated in 5 human glioma cell lines (AO2V4, GJC, GJR, NN and NNR) and in normal astrocyte cultures (SC and TM). All 5 glioma cell lines showed an anti-proliferative response to IFN- whereas normal glial cells were non-responsive. IFN- at 10, 100 and 500 U/ml lead to a 30%,70% and 80% relative decrease in cell number after 12 days, respectively in AO2V4 cells. GJC and GJR cell lines also responded significantly to the lowest concentration of IFN- tested and at 500 U/ml the relative cell number decreased 55%. The NN and NNR cells were the least responsive to IFN- with maximum growth inhibition of 30% at 500 U IFN-/ml. Following treatment with IFN-, AO2V4, GJC, GJR and normal astrocytes all expressed mRNA encoding the anti-viral protein, 2-5A synthetase demonstrating that IFN- bound to receptors on all four cell lines and activated signal transduction pathways required for induction of an anti-viral protein. A determination of the relative number of viable cells showed that none of these cells exhibited a significant decrease in cell viability. Since the antiproliferative response to IFN- was not primarily due to cell death, the effect of IFN- on cell cycle progression was evaluated by flow cytometry. All treated glioma cell lines showed a relative increase in proportion of cells in S phase. AO2V4 cells had a 50%–80% increase in the percentage of cells in S phase, whereas GJC, GJR and NNR had percentage increases of 20%–40%. IFN- treatment of normal astrocytes did not significantly alter their cell cycle profile. These data suggest that IFN- exerts its antiproliferative effect on glioma cells by arresting the ordered progression through S phase or decreasing entry into G2/M phase of the cell cycle.  相似文献   
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