首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1362041篇
  免费   104981篇
  国内免费   6255篇
耳鼻咽喉   17008篇
儿科学   44048篇
妇产科学   36702篇
基础医学   200145篇
口腔科学   36349篇
临床医学   133572篇
内科学   261164篇
皮肤病学   26613篇
神经病学   112786篇
特种医学   49134篇
外国民族医学   373篇
外科学   186215篇
综合类   35763篇
现状与发展   23篇
一般理论   460篇
预防医学   116930篇
眼科学   29517篇
药学   102798篇
  49篇
中国医学   5661篇
肿瘤学   77967篇
  2021年   12160篇
  2019年   12421篇
  2018年   17067篇
  2017年   13237篇
  2016年   14032篇
  2015年   16525篇
  2014年   22508篇
  2013年   33893篇
  2012年   47011篇
  2011年   49625篇
  2010年   29175篇
  2009年   26690篇
  2008年   44690篇
  2007年   47065篇
  2006年   46975篇
  2005年   45180篇
  2004年   42710篇
  2003年   40621篇
  2002年   39166篇
  2001年   61480篇
  2000年   63052篇
  1999年   52638篇
  1998年   14784篇
  1997年   13467篇
  1996年   13252篇
  1995年   12592篇
  1994年   11738篇
  1993年   10980篇
  1992年   41602篇
  1991年   40792篇
  1990年   39485篇
  1989年   37369篇
  1988年   34610篇
  1987年   33713篇
  1986年   32176篇
  1985年   30650篇
  1984年   23037篇
  1983年   19593篇
  1982年   11753篇
  1979年   20806篇
  1978年   14814篇
  1977年   12064篇
  1976年   11876篇
  1975年   12110篇
  1974年   14800篇
  1973年   14472篇
  1972年   13356篇
  1971年   12418篇
  1970年   11486篇
  1969年   10410篇
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
81.
Annals of Nuclear Medicine - The Response Evaluation Criteria In Solid Tumors (RECIST) is the most used radiological method for evaluating response after peptide receptor radionuclide therapy...  相似文献   
82.
83.
84.
85.
Porocarcinoma is an unusual, locally aggressive and potentially fatal neoplasm. Several cutaneous malignancies have been described in association with porocarcinoma, including squamous cell carcinoma, basal cell carcinoma and tricholemmal carcinoma. Previous reports have indicated that the occurrence of malignant tumours in combination with porocarcinoma is extremely rare, in particular with regard to Bowen disease (BD). We report an uncommon case of porocarcinoma occurring synchronously in a single BD lesion in a 63‐year‐old woman with multiple BD lesions. The clinical and histological findings confirmed this diagnosis.  相似文献   
86.
Reactive lymphoid infiltrates of the skin composed predominantly of gamma‐delta (γδ) T cells are not well described in the literature. Herein we report a case of an otherwise healthy 4‐year‐old male who presented with a waxing and waning papular rash characterized by small, discrete crusted papules spread across his trunk, face and extremities. Clinical evaluation revealed no evidence of systemic disease. Microscopic examination revealed a dermal, perivascular infiltrate of highly atypical lymphocytes with a γδ T cell phenotype, worrisome for primary cutaneous γδ T cell lymphoma. The clinical course, however, was that of a reactive condition and prompted consideration of a diagnosis of pityriasis lichenoides et varioliformis acuta (PLEVA) and lymphomatoid papulosis (LyP). In many ways, this case defies current classification schemes and seems to expand the spectrum of reactive γδ T cell infiltrates of the skin.  相似文献   
87.
88.
BackgroundIn the field of transplantation, inducing immune tolerance in recipients is of great importance. Blocking co-stimulatory molecule using anti-CD28 antibody could induce tolerance in a rat kidney transplantation model. Myeloid-derived suppressor cells (MDSCs) reveals strong immune suppressive abilities in kidney transplantation. Here we analyzed key genes of MDSCs leading to transplant tolerance in this model.MethodsMicroarray data of rat gene expression profiles under accession number GSE28545 in the Gene Expression Omnibus (GEO) database were analyzed. Running the LIMMA package in R language, the differentially expressed genes (DEGs) were found. Enrichment analysis of the DEGs was conducted in the Database for Annotation, Visualization and Integrated Discovery (DAVID) database to explore gene ontology (GO) annotation and their Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Their protein-protein interactions (PPIs) were provided by STRING database and was visualized in Cytoscape. Hub genes were carried out by CytoHubba.ResultsThree hundred and thirty-eight DEGs were exported, including 27 upregulated and 311 downregulated genes. The functions and KEGG pathways of the DEGs were assessed and the PPI network was constructed based on the string interactions of the DEGs. The network was visualized in Cytoscape; the entire PPI network consisted of 192 nodes and 469 edges. Zap70, Cdc42, Stat1, Stat4, Ccl5 and Cxcr3 were among the hub genes.ConclusionsThese key genes, corresponding proteins and their functions may provide valuable background for both basic and clinical research and could be the direction of future studies in immune tolerance, especially those examining immunocyte-induced tolerance.  相似文献   
89.
Bowel diseases of prematurity, including necrotizing enterocolitis, are dreaded ailments of neonates. Early diagnosis is difficult, with clinical and radiographic findings often inconclusive. We present a novel use of contrast-enhanced ultrasound in detection of pediatric bowel disease. Early identification of compromised blood flow or an at-risk bowel can be quantitatively detected and monitored. This ability has implications for guidance of emerging therapies, allowing targeting of inflammation. These findings represent an advancement in detection of bowel disease in neonates.  相似文献   
90.
A 17‐year‐old boy presented with recurring severe dermatitis of the face of 5‐months duration that resembled impetigo. He had been treated with several courses of antibiotics without improvement. Biopsy showed changes consistent with allergic contact dermatitis and patch testing later revealed sensitization to benzoyl peroxide, which the patient had been using for the treatment of acne vulgaris.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号