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   620206篇
  免费   59237篇
  国内免费   39496篇
耳鼻咽喉   5336篇
儿科学   9081篇
妇产科学   5621篇
基础医学   54515篇
口腔科学   10668篇
临床医学   82880篇
内科学   71455篇
皮肤病学   7018篇
神经病学   22831篇
特种医学   22512篇
外国民族医学   224篇
外科学   55702篇
综合类   139178篇
现状与发展   152篇
一般理论   32篇
预防医学   57920篇
眼科学   13370篇
药学   71980篇
  768篇
中国医学   48325篇
肿瘤学   39371篇
  2024年   2458篇
  2023年   8462篇
  2022年   21951篇
  2021年   27683篇
  2020年   22991篇
  2019年   16017篇
  2018年   16830篇
  2017年   18402篇
  2016年   15819篇
  2015年   25983篇
  2014年   33336篇
  2013年   34855篇
  2012年   50798篇
  2011年   55683篇
  2010年   43337篇
  2009年   37418篇
  2008年   41639篇
  2007年   40538篇
  2006年   37584篇
  2005年   33238篇
  2004年   22341篇
  2003年   19885篇
  2002年   15828篇
  2001年   13965篇
  2000年   12595篇
  1999年   9897篇
  1998年   5624篇
  1997年   5364篇
  1996年   4241篇
  1995年   3965篇
  1994年   3376篇
  1993年   2179篇
  1992年   2557篇
  1991年   2203篇
  1990年   1884篇
  1989年   1610篇
  1988年   1335篇
  1987年   1246篇
  1986年   1015篇
  1985年   731篇
  1984年   407篇
  1983年   302篇
  1982年   184篇
  1981年   169篇
  1980年   119篇
  1979年   157篇
  1978年   74篇
  1977年   57篇
  1974年   42篇
  1972年   40篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
83.
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   
84.
The present study compared the level of occupational strain and work ability among Han, Hui, Uygur, Hui, and Kazakh teachers, and explored ethnic differences based on the associations of psychosocial factors at work, occupational strain, and work ability. A cross-sectional survey was conducted among 2,941 teachers in primary and secondary schools in Xinjiang Province, China. Psychosocial factors, occupational strain, and work ability were measured using the Occupation Stress Inventory—Revised Edition (OSI-R) and Work Ability Index. Han and Hui teachers experienced reduced work ability compared with Uygur and Kazakh teachers, and this finding was caused, in part, by exposure to psychosocial factors at work. The vocational and psychological strains caused by these factors play an important role in reduced work ability among all ethnic teacher groups. The findings indicate the importance of taking action to reduce occupational strain for promoting teachers' work ability in multiethnic workplaces.  相似文献   
85.
86.
87.
陈海  杨黎  王晓华 《医学综述》2016,(4):778-781
目的研究葛根素联合复方樟柳碱注射液对眼底病患者的治疗效果及对血液流变学指标的影响。方法选择2013年4月至2014年4月在绵阳市第三人民医院眼科进行眼底病治疗的患者100例,并按入院顺序抽签随机分为观察组和对照组,各50例。对照组进行葛根素常规治疗(葛根素注射液0.4 g加入生理盐水250 m L中静脉滴注,每日1次,1个疗程14 d,1个疗程后停药3 d,再进行下一疗程),观察组在此基础上联合复方樟柳碱注射液进行治疗(采用复方樟柳碱2 m L在患者颞浅动脉旁行皮下注射,每日1次,1个疗程14 d,完成1个疗程后停药3 d,再换肾俞穴进行注射,1个疗程后停药3 d,再进行第一个疗程的用药)。3个疗程后,比较两组患者治疗前后血液流变学的变化、术后复发率和不良反应情况及患者的治疗效果。结果治疗后,观察组全血黏度为(4.82±0.41)m Pa·s明显低于对照组的(5.56±0.39)m Pa·s,红细胞聚集指数(3.80±0.41)明显低于对照组(4.77±0.55),纤维蛋白原(4.20±0.24)g/L明显低于对照组(5.25±0.43)g/L,差异均有统计学意义(t=9.247,9.998,15.077,P<0.01);观察组患者治疗后复发率为2.0%(1/50),不良反应的总发生率为4.0%(2/50),分别低于对照组14.0%(7/50)和18.0%(9/50)(P<0.01);观察组患者的总有效率为98.0%(49/50),显著高于对照组的82.0%(41/50)(P<0.05)。结论葛根素和复方樟柳碱注射液联合治疗眼底病患者,可改善患者血液流变学,并提高临床治疗效果。  相似文献   
88.
89.
90.
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   
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