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   232739篇
  免费   64627篇
  国内免费   1277篇
耳鼻咽喉   4183篇
儿科学   9064篇
妇产科学   4137篇
基础医学   25978篇
口腔科学   11651篇
临床医学   41655篇
内科学   57827篇
皮肤病学   11661篇
神经病学   28690篇
特种医学   7286篇
外国民族医学   3篇
外科学   40028篇
综合类   497篇
现状与发展   40篇
一般理论   68篇
预防医学   21373篇
眼科学   4696篇
药学   10660篇
中国医学   1237篇
肿瘤学   17909篇
  2024年   783篇
  2023年   5374篇
  2022年   1594篇
  2021年   5089篇
  2020年   10909篇
  2019年   13803篇
  2018年   16687篇
  2017年   17855篇
  2016年   18929篇
  2015年   19035篇
  2014年   21937篇
  2013年   25270篇
  2012年   11610篇
  2011年   12038篇
  2010年   16986篇
  2009年   15450篇
  2008年   9495篇
  2007年   7817篇
  2006年   8979篇
  2005年   7401篇
  2004年   6642篇
  2003年   6103篇
  2002年   6038篇
  2001年   3658篇
  2000年   2944篇
  1999年   2818篇
  1998年   2798篇
  1997年   2529篇
  1996年   2448篇
  1995年   2206篇
  1994年   1514篇
  1993年   1307篇
  1992年   1057篇
  1991年   929篇
  1990年   778篇
  1989年   755篇
  1988年   735篇
  1987年   605篇
  1986年   576篇
  1985年   485篇
  1984年   477篇
  1983年   479篇
  1982年   460篇
  1981年   414篇
  1980年   327篇
  1979年   226篇
  1978年   272篇
  1977年   257篇
  1976年   201篇
  1972年   176篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
52.
53.
Bowel diseases of prematurity, including necrotizing enterocolitis, are dreaded ailments of neonates. Early diagnosis is difficult, with clinical and radiographic findings often inconclusive. We present a novel use of contrast-enhanced ultrasound in detection of pediatric bowel disease. Early identification of compromised blood flow or an at-risk bowel can be quantitatively detected and monitored. This ability has implications for guidance of emerging therapies, allowing targeting of inflammation. These findings represent an advancement in detection of bowel disease in neonates.  相似文献   
54.
55.
The yeast Saccharomyces cerevisiae is a useful model for studying the influence of different stress factors on eukaryotic cells. In this work we used the pesticide imidacloprid, in the Confidor formulation, as the stress factor and analyzed its influence on the metabolic activity, proteome and lipid content and composition of Saccharomyces cerevisiae yeast. During the cultivation of yeast, the lowest recommended application dose of Confidor (0.025%, v/v) was added to the growth media and its influence on the mitochondria, cytosol with microsomes, and the whole yeast cells was monitored. The results show that under the stress provoked by the toxic effects of Confidor, yeast cells density significantly decreased and the percentage of metabolically disturbed cells significantly increased comparing with untreated control. Also, there was a downregulation of majority of glycolytic, gluconeogenesis, and TCA cycle enzymes (Fba1, Adh1, Hxk2, Tal1, Tdh1,Tdh3, Eno1) thus providing enough acetyl‐CoA for the lipid restructuring and accumulation mechanism since we have found the changes in the cell and mitochondrial lipid content and FA composition. This data suggest that lipids could be the molecules that orchestrate the answer of the cells in the stress response to the Confidor treatment.  相似文献   
56.
57.
The association between asbestos exposure, mainly in occupational settings, and malignant mesothelioma has been well established; this has prompted several countries to establish mesothelioma epidemiologic surveillance programs often at the request of national agencies. This review compares currently existing mesothelioma registries worldwide to develop a concept model for a US real-time case capture mesothelioma registry. Five countries were identified with a mesothelioma specific registry, including Italy, France, UK, Australia, and South Korea. All, except the UK, used interviews to collect exposure data. Linkage with the national death index was available or was in future plans for all registries. The registries have limited information on treatment, quality of life, and other patient-centered outcomes such as symptoms and pain management. To thoroughly collect exposure data, “real-time” enrollment is preferable; to maximize the capture of mesothelioma cases, optimal coverage, and a simplified consent process are needed.  相似文献   
58.
Acute lung injury (ALI) caused by systemic inflammatory response remains a leading cause of morbidity and mortality in critically ill patients. Management of patients with sepsis is largely limited to supportive therapies, reflecting an incomplete understanding of the underlying pathophysiology. Furthermore, there have been limited advances in the treatments for ALI. In this study, lung function and a histological analysis were performed to evaluate the impact of transient receptor potential vanilloid‐1 receptor (TRPV1) antagonist (capsazepine; CPZ) on the lipopolysaccharide (LPS)‐induced lung injury in mice. For this, adult mice pre‐treated with CPZ or vehicle received intraperitoneal injections of LPS or saline and 24 hr after, the mice were anaesthetized, and lung mechanics was evaluated. The LPS‐challenged mice exhibited substantial mechanical impairment, characterized by increases in respiratory system resistance, respiratory system elastance, tissue damping and tissue elastance. The pre‐treatment with CPZ prevented the increase in respiratory system resistance and decreased the increase in tissue damping during endotoxemia. In addition, mice pre‐treated with CPZ had an attenuated lung injury evidenced by reduction on collapsed area of the lung parenchyma induced by LPS. This suggests that the TRPV1 antagonist capsazepine has a protective effect on lung mechanics in ALI during endotoxemia and that it may be a target for enhanced therapeutic efficacy in ALI.  相似文献   
59.
60.
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