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   1695篇
  免费   103篇
  国内免费   9篇
耳鼻咽喉   23篇
儿科学   40篇
妇产科学   34篇
基础医学   204篇
口腔科学   29篇
临床医学   128篇
内科学   356篇
皮肤病学   27篇
神经病学   85篇
特种医学   38篇
外国民族医学   1篇
外科学   431篇
综合类   45篇
一般理论   1篇
预防医学   82篇
眼科学   63篇
药学   106篇
中国医学   7篇
肿瘤学   107篇
  2023年   8篇
  2022年   48篇
  2021年   83篇
  2020年   57篇
  2019年   54篇
  2018年   56篇
  2017年   37篇
  2016年   42篇
  2015年   56篇
  2014年   81篇
  2013年   102篇
  2012年   150篇
  2011年   119篇
  2010年   81篇
  2009年   58篇
  2008年   96篇
  2007年   87篇
  2006年   95篇
  2005年   89篇
  2004年   84篇
  2003年   76篇
  2002年   52篇
  2001年   21篇
  2000年   21篇
  1999年   14篇
  1998年   18篇
  1997年   14篇
  1996年   7篇
  1995年   13篇
  1994年   4篇
  1993年   9篇
  1992年   9篇
  1991年   11篇
  1990年   8篇
  1989年   4篇
  1988年   8篇
  1987年   5篇
  1985年   2篇
  1984年   2篇
  1983年   3篇
  1982年   3篇
  1981年   3篇
  1979年   3篇
  1978年   5篇
  1977年   3篇
  1976年   3篇
  1975年   1篇
  1973年   1篇
  1970年   1篇
排序方式: 共有1807条查询结果,搜索用时 562 毫秒
1.
2.
The present investigation was aimed at studying the possible role of curcumin against N-nitrosodiethylamine (NDEA)-induced toxicity in albino rats. Administration of NDEA to rats at a concentration of 0.1 mg/ml in drinking water ad libitum for 21 days produced toxicity in them, which was evident from histopathological changes in the rat livers, and increased levels of blood serum enzyme markers, i.e. aspartate transaminase, alanine transaminase, alkaline phosphatase, and lactate dehydrogenase. In addition, the levels of oxidative stress markers like lipid peroxidation (LPO), protein carbonyl (PCC), and glutathione-S-transferase (GST) activity were elevated and the total glutathione (GSH) content was reduced in the livers. The administration of curcumin to rats at concentrations of 10, 20, and 40 mg/ml in drinking water along with 0.1 mg/ml of NDEA for 21 days effectively suppressed NDEA-induced toxicity and also resulted in a dose-dependent reduction in the levels of blood serum enzyme markers (AST, ALT, ALP, and LDH). Moreover, LPO, PCC, and GST activity were reduced and the GSH level was increased upon the administration of curcumin along with NDEA. The results obtained for the comet assay in rat hepatocytes and blood lymphocytes showed a significant dose-dependent decrease in the mean tail length. The micronucleus assay performed on rat hepatocytes also showed a dose-dependent reduction in the frequency of micronucleated cells along with curcumin administration. These results suggest that curcumin has a protective role against NDEA-induced toxicity in albino rats.  相似文献   
3.
4.
5.

Background and Purpose:   

Management of rib fractures constitutes a major part of the trauma workload of any unit. Rib fractures result in disrupted chest wall mechanics and ventilatory insufficiency. The ability of a lung injury scoring system to predict the degree of respiratory dysfunction after rib fractures was evaluated.  相似文献   
6.
The distinction between atypical hyperplasia and carcinoma in situ in breast lesions can be difficult. The identification of myoepithelial cell layers may be helpful in establishing a diagnosis of proliferative breast disease vs. intraepithelial neoplasia. We reviewed pathologic material on 20 cases of atypical hyperplasia and 29 cases of carcinoma in situ. Immunohistochemical stains were employed against muscle-specific actin, S-100 protein, and cytokeratin to identify myoepithelial cells and to recognize different staining patterns. In atypical hyperplasia, muscle-specific actin staining identified myoepithelial cells in fine branching fibrovascular layers or as scattered cells between other proliferating cells. This pattern was absent in carcinoma in situ. S-100 protein showed more positive staining in atypical hyperplasia than in carcinoma in situ with patterns distinct from muscle-specific actin. Immunostaining for cytokeratin demonstrated distinctly different patterns between the two lesions. This study suggests that muscle-specific actin, S-100 protein, and cytokeratin in combination may assist in distinguishing proliferative breast disease with atypia from carcinoma in situ.  相似文献   
7.
8.
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