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   3458528篇
  免费   295516篇
  国内免费   19841篇
耳鼻咽喉   46673篇
儿科学   108994篇
妇产科学   87684篇
基础医学   550429篇
口腔科学   91274篇
临床医学   318429篇
内科学   605139篇
皮肤病学   90898篇
神经病学   297059篇
特种医学   134866篇
外国民族医学   380篇
外科学   530444篇
综合类   116681篇
现状与发展   46篇
一般理论   2521篇
预防医学   290128篇
眼科学   80687篇
药学   240497篇
  78篇
中国医学   14216篇
肿瘤学   166762篇
  2021年   60631篇
  2020年   39088篇
  2019年   61989篇
  2018年   75716篇
  2017年   57726篇
  2016年   63371篇
  2015年   78608篇
  2014年   114519篇
  2013年   179760篇
  2012年   107038篇
  2011年   108783篇
  2010年   124086篇
  2009年   126351篇
  2008年   91577篇
  2007年   95175篇
  2006年   105686篇
  2005年   101054篇
  2004年   100612篇
  2003年   90594篇
  2002年   79227篇
  2001年   96966篇
  2000年   89728篇
  1999年   91414篇
  1998年   66119篇
  1997年   63961篇
  1996年   61537篇
  1995年   56883篇
  1994年   51009篇
  1993年   47283篇
  1992年   63495篇
  1991年   60421篇
  1990年   57417篇
  1989年   56686篇
  1988年   52377篇
  1987年   51722篇
  1986年   48737篇
  1985年   49192篇
  1984年   45735篇
  1983年   41927篇
  1982年   40998篇
  1981年   38818篇
  1980年   36467篇
  1979年   37312篇
  1978年   33956篇
  1977年   31121篇
  1976年   28623篇
  1975年   26936篇
  1974年   27729篇
  1973年   26669篇
  1972年   24785篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
ObjectiveClinical specialty societies recommend long-acting reversible contraceptives (LARCs) as first-line contraception for adolescent women. We evaluated whether a combined educational and process improvement intervention enhanced LARC placement in primary care within an integrated health care system.MethodsThe intervention included journal clubs, live continuing education, point-of-care guidelines, and new patient materials. We conducted a retrospective cohort study across 3 time periods: baseline (January 2013?September 2015), early implementation (October 2015–March 2016), and full implementation (April 2016–June 2017). The primary outcome was the proportion of LARCs placed by primary care clinicians among women aged 13 to 18 years compared with gynecology clinicians.ResultsKaiser Foundation Health Plan of Colorado cared for approximately 20,000 women aged 13 to 18 years in each calendar quarter between 2013 and 2017. Overall, LARC placement increased from 7.0 per 1000 members per quarter at baseline to 13.0 per 1000 during the full intervention. Primary care clinicians placed 6.2% of all LARCs in 2013, increasing to 32.1% by 2017 (P < .001), including 45.5% of contraceptive implants. Clinicians who attended educational sessions were more likely to adopt LARCs than those who did not (17.9% vs 6.4% respectively, P = .009). Neither overall LARC placement rates (relative risk, 1.9; 95% confidence interval, 0.7?5.6) nor contraceptive implant rates (relative risk, 3.0; 95% confidence interval, 0.9?9.8) increased significantly in clinicians who attended educational activities.ConclusionsThis multimodal intervention was associated with increased LARC placement for adolescent women in primary care. The combination of education and process improvement is a promising strategy to promote clinician behavior change.  相似文献   
994.
995.
996.
997.
李焱  翟凤霞 《陕西中医》2020,(5):660-662
妊娠期间,咳嗽不已,称"妊娠咳嗽",亦称"子嗽",孕妇咳嗽日久未见好转,咳嗽胸痛甚则咳而呕吐,或咳嗽剧烈或久咳不愈,可损伤胎气,导致堕胎、小产。笔者运用六经辨证治疗外感型中表寒里热证子嗽,认为此类患者病在太阳阳明,属于寒热错杂之表寒里热,采用《伤寒论》中方证麻杏甘石汤合止嗽散,使热从外泄,宣发卫气,散寒不助热、解表不伤正,故辨证论治取得了显著的疗效。同时子嗽治疗还需注意健脾固肾安胎,应将顾护胎元贯穿治疗妊娠咳嗽的始终。  相似文献   
998.
999.
1000.
Understanding the contribution of endothelial cells to the progenitor pools of adult tissues has the potential to inform therapies for human disease.To address whether endothelial cells transdifferentiate into non-vascular cell types,we performed cell lineage tracing analysis using transgenic mice engineered to express a fluorescent marker following activation by tamoxifen in vascular endothelial cadherin promoter-expressing cells(VEcad-CreERT2;B6 Cg-Gt(ROSA)26Sortm9(CAG-tdTomato)Hze).Activation of target-cell labeling following 1.5 months of ad libitum feeding with tamoxifen-laden chow in 4–5 month-old mice resulted in the tracing of central nervous system and peripheral cells that include:cerebellar granule neurons,ependymal cells,skeletal myocytes,pancreatic beta cells,pancreatic acinar cells,tubular cells in the renal cortex,duodenal crypt cells,ileal crypt cells,and hair follicle stem cells.As Nestin expression has been reported in a subset of endothelial cells,Nes-CreERT2 mice were also utilized in these conditions.The tracing of cells in adult Nes-CreERT2 mice revealed the labeling of canonical progeny cell types such as hippocampal and olfactory granule neurons as well as ependymal cells.Interestingly,Nestin tracing also labeled skeletal myocytes,ileal crypt cells,and sparsely marked cerebellar granule neurons.Our findings provide support for endothelial cells as active contributors to adult tissue progenitor pools.This information could be of particular significance for the intravenous delivery of therapeutics to downstream endothelial-derived cellular targets.The animal experiments were approved by the Boise State University Institute Animal Care and Use Committee(approval No.006-AC15-018)on October 31,2018.  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