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   63497篇
  免费   4646篇
  国内免费   148篇
耳鼻咽喉   825篇
儿科学   1740篇
妇产科学   1596篇
基础医学   10454篇
口腔科学   1683篇
临床医学   5983篇
内科学   12723篇
皮肤病学   963篇
神经病学   5952篇
特种医学   2698篇
外国民族医学   45篇
外科学   8215篇
综合类   567篇
一般理论   83篇
预防医学   4940篇
眼科学   1209篇
药学   4594篇
  1篇
中国医学   162篇
肿瘤学   3858篇
  2022年   364篇
  2021年   1028篇
  2020年   653篇
  2019年   924篇
  2018年   1126篇
  2017年   781篇
  2016年   917篇
  2015年   1089篇
  2014年   1339篇
  2013年   2328篇
  2012年   2993篇
  2011年   3087篇
  2010年   2231篇
  2009年   1869篇
  2008年   2797篇
  2007年   2937篇
  2006年   2925篇
  2005年   2767篇
  2004年   2826篇
  2003年   2569篇
  2002年   2640篇
  2001年   2156篇
  2000年   2213篇
  1999年   1983篇
  1998年   883篇
  1997年   747篇
  1996年   654篇
  1995年   675篇
  1994年   563篇
  1993年   614篇
  1992年   1448篇
  1991年   1395篇
  1990年   1336篇
  1989年   1327篇
  1988年   1101篇
  1987年   1106篇
  1986年   1046篇
  1985年   959篇
  1984年   692篇
  1983年   649篇
  1982年   458篇
  1981年   442篇
  1980年   380篇
  1979年   624篇
  1978年   376篇
  1977年   358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 31 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