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   1675055篇
  免费   115801篇
  国内免费   2390篇
耳鼻咽喉   23512篇
儿科学   55616篇
妇产科学   47811篇
基础医学   254903篇
口腔科学   45407篇
临床医学   145180篇
内科学   321062篇
皮肤病学   36024篇
神经病学   125214篇
特种医学   65381篇
外国民族医学   410篇
外科学   256859篇
综合类   32850篇
现状与发展   2篇
一般理论   399篇
预防医学   122906篇
眼科学   38795篇
药学   128453篇
  2篇
中国医学   3254篇
肿瘤学   89206篇
  2018年   16252篇
  2016年   13862篇
  2015年   15819篇
  2014年   21642篇
  2013年   32719篇
  2012年   45899篇
  2011年   49649篇
  2010年   29121篇
  2009年   27022篇
  2008年   47275篇
  2007年   51484篇
  2006年   51772篇
  2005年   50436篇
  2004年   48762篇
  2003年   47314篇
  2002年   46310篇
  2001年   74358篇
  2000年   76231篇
  1999年   64185篇
  1998年   17293篇
  1997年   15068篇
  1996年   15339篇
  1995年   15323篇
  1994年   14424篇
  1993年   13495篇
  1992年   51519篇
  1991年   51963篇
  1990年   51524篇
  1989年   50193篇
  1988年   46714篇
  1987年   45903篇
  1986年   43548篇
  1985年   41634篇
  1984年   31013篇
  1983年   26826篇
  1982年   15497篇
  1981年   13788篇
  1979年   29530篇
  1978年   20767篇
  1977年   17715篇
  1976年   17187篇
  1975年   19302篇
  1974年   22558篇
  1973年   21734篇
  1972年   20528篇
  1971年   19284篇
  1970年   17994篇
  1969年   17125篇
  1968年   16153篇
  1967年   14308篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
Neuroscience and Behavioral Physiology - We present here results from analysis of the formation of brain bioelectrical activity in children and adolescents living in the northern region of Russia...  相似文献   
4.
Oral squamous cell carcinomas (OSCCs) develop in genetically altered epithelium in the mucosal lining, also coined as fields, which are mostly not visible but occasionally present as white oral leukoplakia (OL) lesions. We developed a noninvasive genetic assay using next-generation sequencing (NGS) on brushed cells to detect the presence of genetically altered fields, including those that are not macroscopically visible. The assay demonstrated high accuracy in OL patients when brush samples were compared with biopsies as gold standard. In a cohort of Fanconi anemia patients, detection of mutations in prospectively collected oral brushes predicted oral cancer also when visible abnormalities were absent. We further provide insight in the molecular landscape of OL with frequent changes of TP53, FAT1 and NOTCH1. NGS analysis of noninvasively collected samples offers a highly accurate method to detect genetically altered fields in the oral cavity, and predicts development of OSCC in high-risk individuals. Noninvasive genetic screening can be employed to screen high-risk populations for cancer and precancer, map the extension of OL lesions beyond what is visible, map the oral cavity for precancerous changes even when visible abnormalities are absent, test accuracy of promising imaging modalities, monitor interventions and determine genetic progression as well as the natural history of the disease in the human patient.  相似文献   
5.
Jones type fifth metatarsal fractures pose a challenge to the foot and ankle surgeon, given documented high nonunion rates as well as high complication rates including hardware prominence, nerve injury, and screw breakage for existing treatment modalities including screw and plantar plate fixation. We call for the design of innovative Jones-fracture specific implants which contour to the natural curve of the fifth metatarsal. Future research should aim to expand upon existing literature for Jones fracture fixation and evaluate efficacy of novel implants which are designed to address unacceptably high complication rates for existing treatment modalities.  相似文献   
6.
7.
8.
9.
Microbial co-infections are another primary concern in patients with coronavirus disease 2019 (COVID-19), yet it is an untouched area among researchers. Preliminary data and systematic reviews only show the type of pathogens responsible for that, but its pathophysiology is still unknown. Studies show that these microbial co-infections are hospital-acquired/nosocomial infections, and patients admitted to intensive care units with invasive mechanical ventilation are highly susceptible to it. Patients with COVID-19 had elevated inflammatory cytokines and a weakened cell-mediated immune response, with lower CD4+ T and CD8+ T cell counts, indicating vulnerability to various co-infections. Despite this, there are only a few studies that recommend the management of co-infections.  相似文献   
10.
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