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   65628篇
  免费   4975篇
  国内免费   148篇
耳鼻咽喉   847篇
儿科学   1797篇
妇产科学   1673篇
基础医学   10834篇
口腔科学   1751篇
临床医学   6241篇
内科学   13086篇
皮肤病学   1053篇
神经病学   6103篇
特种医学   2714篇
外国民族医学   45篇
外科学   8499篇
综合类   580篇
一般理论   83篇
预防医学   5221篇
眼科学   1282篇
药学   4718篇
中国医学   164篇
肿瘤学   4060篇
  2022年   391篇
  2021年   1056篇
  2020年   667篇
  2019年   941篇
  2018年   1156篇
  2017年   805篇
  2016年   956篇
  2015年   1114篇
  2014年   1376篇
  2013年   2376篇
  2012年   3073篇
  2011年   3176篇
  2010年   2284篇
  2009年   1914篇
  2008年   2869篇
  2007年   3020篇
  2006年   3025篇
  2005年   2845篇
  2004年   2917篇
  2003年   2651篇
  2002年   2712篇
  2001年   2223篇
  2000年   2295篇
  1999年   2034篇
  1998年   904篇
  1997年   763篇
  1996年   662篇
  1995年   695篇
  1994年   588篇
  1993年   629篇
  1992年   1503篇
  1991年   1459篇
  1990年   1379篇
  1989年   1369篇
  1988年   1144篇
  1987年   1133篇
  1986年   1097篇
  1985年   993篇
  1984年   730篇
  1983年   686篇
  1982年   481篇
  1981年   467篇
  1980年   398篇
  1979年   663篇
  1978年   401篇
  1977年   378篇
  1975年   409篇
  1974年   444篇
  1973年   372篇
  1972年   384篇
排序方式: 共有10000条查询结果,搜索用时 15 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