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   63474篇
  免费   4650篇
  国内免费   147篇
耳鼻咽喉   824篇
儿科学   1741篇
妇产科学   1603篇
基础医学   10478篇
口腔科学   1687篇
临床医学   5987篇
内科学   12731篇
皮肤病学   966篇
神经病学   5966篇
特种医学   2653篇
外国民族医学   45篇
外科学   8228篇
综合类   538篇
一般理论   83篇
预防医学   4940篇
眼科学   1200篇
药学   4587篇
中国医学   162篇
肿瘤学   3852篇
  2022年   364篇
  2021年   1028篇
  2020年   649篇
  2019年   918篇
  2018年   1125篇
  2017年   781篇
  2016年   916篇
  2015年   1085篇
  2014年   1336篇
  2013年   2327篇
  2012年   2990篇
  2011年   3085篇
  2010年   2230篇
  2009年   1868篇
  2008年   2798篇
  2007年   2938篇
  2006年   2933篇
  2005年   2765篇
  2004年   2827篇
  2003年   2574篇
  2002年   2640篇
  2001年   2160篇
  2000年   2215篇
  1999年   1992篇
  1998年   883篇
  1997年   738篇
  1996年   653篇
  1995年   674篇
  1994年   558篇
  1993年   608篇
  1992年   1451篇
  1991年   1395篇
  1990年   1336篇
  1989年   1322篇
  1988年   1103篇
  1987年   1102篇
  1986年   1049篇
  1985年   964篇
  1984年   693篇
  1983年   648篇
  1982年   461篇
  1981年   440篇
  1980年   379篇
  1979年   624篇
  1978年   375篇
  1977年   357篇
  1975年   373篇
  1974年   414篇
  1973年   347篇
  1972年   340篇
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
1.
2.
3.
4.
5.
6.
Clinical Oral Investigations - The aim of this study was the analysis of WNT10A variants in seven families of probands with various forms of tooth agenesis and self-reported family history of...  相似文献   
7.
The aim of this study was to analyse the effect of body mass index (BMI), both low and high values, on the perioperative complication rate in patients with oral squamous cell carcinoma (OSCC). The medical records of 259 patients operated between 2014 and 2017 for OSCC were reviewed. Univariate and multivariate analyses were performed. Sixty of the 259 patients developed 87 complications. Low or high BMI was not associated with the perioperative complication rate. A longer operating time and increased blood loss were associated with a higher perioperative complication rate and higher Clavien–Dindo grade. Low BMI, American Society of Anesthesiologists score 2 and 3, a longer operating time, and increased blood loss were associated with a longer hospital stay. Low BMI was associated with a longer hospital stay. Neither low nor high BMI was associated with the perioperative complication rate. A longer operating time and increased blood loss were associated with a higher perioperative complication rate and higher Clavien–Dindo grade.  相似文献   
8.
Genetic and epigenetic alterations importantly contribute to the pathogenesis of lung cancer. In the study, we measured the frequency and distribution of molecular abnormalities of EGFR as well as the aberrant promoter methylations of BRCA1, MGMT, MLH1, and RASSF1A in Vietnamese lung adenocarcinomas. We investigated the association between genetic and epigenetic alteration, and between each abnormality with clinicopathologic parameters. Somatic EGFR mutation that was found in 49/139 (35.3%) lung adenocarcinomas showed a significant association with young age, female gender, and non-smokers. EGFR overexpression was identified in 82 tumors (59.0%) and statistical relationships with EGFR or BRCA1 methylation but not EGFR mutation. In addition, EGFR, BRCA1, MGMT, MLH1, and RASSF1A methylations were found in 33 (23.7%), 41 (29.5%), 46 (33.1%), 28 (20.1%), and 41 (29.5%) cases of a total of 139 lung adenocarcinomas, respectively. The RASSF1A methylation was found to be linked to the smoking habit. Methylations in MGMT and RASSF1A were also found to correlate with metastasis status. Furthermore, the distribution of EGFR mutation and that of BRCA1, MGMT or RASSF1A methylation were significantly exclusive in lung adenocarcinomas. The main finding of our study demonstrate that epigenetic abnormalities might play a critical role for the lung tumorigenesis in patients with smoking history and metastasis, and partly affect the predictive value of EGFR mutations through blocking expression due to promoter EGFR hypermethylation. Mutually exclusive distribution of genetic and epigenetic alterations reflects differently biological characteristics in the etiology of lung adenocarcinomas.  相似文献   
9.
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