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   82807篇
  免费   6019篇
  国内免费   232篇
耳鼻咽喉   1010篇
儿科学   2266篇
妇产科学   2080篇
基础医学   12812篇
口腔科学   2105篇
临床医学   8072篇
内科学   16402篇
皮肤病学   1141篇
神经病学   7966篇
特种医学   3301篇
外国民族医学   48篇
外科学   11461篇
综合类   769篇
一般理论   99篇
预防医学   6511篇
眼科学   1669篇
药学   6083篇
中国医学   176篇
肿瘤学   5087篇
  2022年   424篇
  2021年   1346篇
  2020年   861篇
  2019年   1268篇
  2018年   1539篇
  2017年   1073篇
  2016年   1245篇
  2015年   1488篇
  2014年   1912篇
  2013年   3184篇
  2012年   4320篇
  2011年   4485篇
  2010年   3021篇
  2009年   2524篇
  2008年   4117篇
  2007年   4455篇
  2006年   4215篇
  2005年   4059篇
  2004年   4182篇
  2003年   3751篇
  2002年   3814篇
  2001年   2345篇
  2000年   2355篇
  1999年   2182篇
  1998年   1138篇
  1997年   959篇
  1996年   823篇
  1995年   815篇
  1994年   696篇
  1993年   746篇
  1992年   1589篇
  1991年   1517篇
  1990年   1446篇
  1989年   1416篇
  1988年   1186篇
  1987年   1197篇
  1986年   1133篇
  1985年   1031篇
  1984年   778篇
  1983年   738篇
  1982年   550篇
  1981年   537篇
  1980年   458篇
  1979年   692篇
  1978年   442篇
  1977年   414篇
  1975年   436篇
  1974年   467篇
  1973年   398篇
  1972年   394篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
3.
4.
5.
6.
7.
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   
8.
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   
9.
10.
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   
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