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   764篇
  免费   70篇
  国内免费   43篇
耳鼻咽喉   11篇
儿科学   5篇
妇产科学   17篇
基础医学   107篇
口腔科学   8篇
临床医学   35篇
内科学   121篇
皮肤病学   14篇
神经病学   51篇
特种医学   18篇
外科学   26篇
综合类   115篇
预防医学   40篇
眼科学   2篇
药学   202篇
中国医学   50篇
肿瘤学   55篇
  2023年   11篇
  2022年   20篇
  2021年   34篇
  2020年   29篇
  2019年   33篇
  2018年   29篇
  2017年   36篇
  2016年   38篇
  2015年   30篇
  2014年   81篇
  2013年   87篇
  2012年   61篇
  2011年   84篇
  2010年   49篇
  2009年   58篇
  2008年   47篇
  2007年   43篇
  2006年   37篇
  2005年   27篇
  2004年   16篇
  2003年   12篇
  2002年   6篇
  2001年   2篇
  2000年   2篇
  1999年   2篇
  1998年   2篇
  1982年   1篇
排序方式: 共有877条查询结果,搜索用时 15 毫秒
1.
2.
Rapid industrial and technological development has impacted ecosystem homeostasis strongly. Arsenic is one of the most detrimental environmental toxins and its management with chelating agents remains a matter of concern due to associated adverse effects. Thus, safer and more effective alternative therapy is required to manage arsenic toxicity. Based on existing evidence, native and indigenous plant-based active biomolecules appear as a promising strategy to mitigate arsenic-induced toxicity with an acceptable safety profile. In this regard, various phytochemicals (flavonoids and stilbenoids) are considered important classes of polyphenolic compounds with antioxidant and chelation effects, which may facilitate the removal of arsenic from the body more effectively and safely with regard to conventional approaches. This review presents an overview of conventional chelating agents and the potential role of flavonoids and stilbenoids in ameliorating arsenic toxicity. This report may provide a roadmap for identifying novel prophylactic/therapeutic strategies for managing arsenic toxicity.  相似文献   
3.
4.
Industrial products contained nano-zinc oxide (ZnONP) can gain access to the aquaculture environment causing hazardous effects on the living biota. Therefore, this work was planned to examine the ameliorative effects of dietary supplementation of lycopene (LYC) and/or resveratrol (RES) against ZnONP toxicity in Nile tilapia. Five groups with 20 fish each were used; Control, received tap water only; ZnONP group, was intoxicated with ZnONP (50 mg/L); ZnONP-LYC group, was exposed to ZnONP and LYC (500 mg/ kg of the diet); ZnONP-RES group, was exposed to ZnONP and RES (50 mg/kg of the diet); ZnONP-LYC-RES group, was exposed to ZnONP and a combination of LYC and RES. The experiment was continued for 30 days. Fish blood and tissues were then assembled for determination of liver and kidney function and oxidative stress status in liver, kidney, and gills tissue. Results revealed a considerable elevation of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), cholesterol, urea, and creatinine with a noticeable lowering of total proteins and albumin serum levels in response to ZnONP intoxication. In addition, there were significant increase in malondialdehyde (MDA) and reduction in the reduced-glutathione (GSH) levels and superoxide dismutase (SOD) and catalase (CAT) activities. However, treatment with LYC and/or RES ameliorated the ZnONP-inflicted oxidative stress which possibly attributed to their beneficial antioxidant activities.  相似文献   
5.
【摘要】白藜芦醇是一种天然的多酚化合物,有预防心血管疾病,预防衰老,抗炎,抗癌等作用。该文总结了近年来白藜芦醇作用于结直肠癌的机制的研究进展,为白藜芦醇的进一步研究提供依据。  相似文献   
6.
7.
8.
ObjectiveBone marrow-derived mesenchymal stem cells (BMSCs) are effective in the treatment of severe acute pancreatitis (SAP), but their therapeutic effects could still be improved. In order to optimize the clinical application of BMSCs, we adopted the strategy of resveratrol (Res) pretreatment of BMSCs (Res-BMSCs) and applied it to a rat model of sodium taurocholate (NaT)-induced acute pancreatitis.MethodsSAP was induced by injection of 3% NaT into the pancreatic duct and successful induction of SAP occurred after 12 h. Rats were treated with BMSCs, Res or BMSCs primed with Res at 40 mmol/L, Vandetanib (ZD6474) daily oral dosages of 50 mg/kg vandetanib.ResultsRes stimulated BMSCs to secrete vascular endothelial growth factor A (VEGFA), activated the downstream phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway, and inhibited pancreatic cell apoptosis. In addition, conditioned medium (CM) from Res-BMSCs enhanced the proliferation of human umbilical vein endothelial cells (HUVECs) in vitro, increased resistance to apoptosis and promoted the expression of angiogenesis-related proteins CD31, VEGF and VEGFR2 in pancreatic tissue, but Vandetanib partly abolished these effects by blocking the VEGFA- mediated pathway.ConclusionResveratrol-preprocessed BMSCs can activate the PI3K/AKT signaling pathway in pancreatic cells and HUVECs through paracrine release of VEGFA; thus, achieving the therapeutic effect of resisting apoptosis of pancreatic cells and promoting regeneration of damaged blood vessels. Res pretreatment may be a new strategy to improve the therapeutic effect of BMSCs on SAP.  相似文献   
9.
10.
Liver diseases are a worldwide medical problem because the liver is the principal detoxifying organ and maintains metabolic homeostasis. The liver metabolizes various compounds that produce free radicals(FR).However, antioxidants scavenge FR and maintain the oxidative/antioxidative balance in the liver. When the liver oxidative/antioxidative balance is disrupted, the state is termed oxidative stress. Oxidative stress leadsto deleterious processes in the liver and produces liver diseases. Therefore, restoring antioxidants is essential to maintain homeostasis. One method of restoring antioxidants is to consume natural compounds with antioxidant capacity. The objective of this review is to provide information pertaining to various antioxidants found in food that have demonstrated utility in improving liver diseases.  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