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   323912篇
  免费   60765篇
  国内免费   1210篇
耳鼻咽喉   4271篇
儿科学   10552篇
妇产科学   5256篇
基础医学   47998篇
口腔科学   9533篇
临床医学   37404篇
内科学   75514篇
皮肤病学   10767篇
神经病学   37008篇
特种医学   10550篇
外国民族医学   11篇
外科学   52085篇
综合类   3610篇
一般理论   342篇
预防医学   25439篇
眼科学   7908篇
药学   22482篇
  4篇
中国医学   1420篇
肿瘤学   23733篇
  2023年   1261篇
  2022年   1781篇
  2021年   6722篇
  2020年   8070篇
  2019年   15589篇
  2018年   15657篇
  2017年   15456篇
  2016年   16537篇
  2015年   17340篇
  2014年   20027篇
  2013年   23681篇
  2012年   22120篇
  2011年   22988篇
  2010年   19257篇
  2009年   14531篇
  2008年   18650篇
  2007年   18432篇
  2006年   18327篇
  2005年   18115篇
  2004年   17020篇
  2003年   15837篇
  2002年   14915篇
  2001年   2928篇
  2000年   2367篇
  1999年   2648篇
  1998年   3118篇
  1997年   2599篇
  1996年   2217篇
  1995年   2124篇
  1994年   1776篇
  1993年   1592篇
  1992年   1303篇
  1991年   1207篇
  1990年   1047篇
  1989年   1030篇
  1988年   1006篇
  1987年   992篇
  1986年   977篇
  1985年   994篇
  1984年   1241篇
  1983年   1151篇
  1982年   1378篇
  1981年   1317篇
  1980年   1158篇
  1979年   743篇
  1978年   770篇
  1977年   659篇
  1976年   603篇
  1975年   479篇
  1974年   488篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
11.
12.
We report a case of benign lymphoplasmacytic plaque (LPP) in a child. These asymptomatic erythematous papulonodular lesions are an emerging clinicopathological entity. Herein, we describe a previously unreported site for LPP lesions, namely, the volar wrist and the distal ipsilateral palm.  相似文献   
13.
14.
15.
16.
It is well recognized that the world population is ageing rapidly. Therefore, it is important to understand ageing processes at the cellular and molecular levels to predict the onset of age‐related diseases and prevent them. Recent research has focused on the identification of ageing biomarkers, including those associated with the properties of the Golgi apparatus. In this context, Golgi‐mediated glycosylation of proteins has been well characterized. Additionally, other studies show that the secretion of many compounds, including pro‐inflammatory cytokines and extracellular matrix–degrading enzymes, is modified during ageing, resulting in physical and functional skin degradation. Since the Golgi apparatus is a central organelle of the secretory pathway, we investigated its structural organization in senescent primary human dermal fibroblasts using confocal and electron microscopy. In addition, we monitored the expression of Golgi‐related genes in the same cells. Our data showed a marked alteration in the Golgi morphology during replicative senescence. In contrast to its small and compact structure in non‐senescent cells, the Golgi apparatus exhibited a large and expanded morphology in senescent fibroblasts. Our data also demonstrated that the expression of many genes related to Golgi structural integrity and function was significantly modified in senescent cells, suggesting a relationship between Golgi apparatus function and ageing.  相似文献   
17.
Radiodermatitis is one of the commonest side effects of radiotherapy. They are usually assessed by semi‐quantitative clinical scores, which are not validated and may be subject to inter‐observer variability. A few previous studies suggested that high‐frequency ultrasonography (HF‐USG) is useful in the assessment of the acute phase of radiation dermatitis in breast cancer patients. (a) To monitor skin changes by HF‐USG during the course of radiotherapy due to head and neck cancers, and (b) to determine whether there is any connection between skin sonograms and the skin scoring criteria. This prospective, observational study includes patients diagnosed with head and neck cancers, treated with radiotherapy or concomitant chemoradiation. The final analysis includes six patients. In every patient, the HF‐USG as well as dermatological assessment (target lesion score—TLS and CACE v. 4.0) were performed 4×: before, in the middle, day after, and 3 months after radiotherapy. There were significant differences between non‐irradiated skin thickness and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P < .0001), as well as between irradiated, unchanged skin thickness (TLS grade 0) and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P = .0002). There was no significant difference between non‐irradiated and irradiated, unchanged skin thickness (TLS grade 0; P = .9318). In four patients, we demonstrated subepidermal low echogenic band (SLEB). HF‐USG can be useful tool to noninvasive and objective assessment of skin changes during radiotherapy.  相似文献   
18.
19.
20.
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