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   8977篇
  免费   512篇
  国内免费   24篇
耳鼻咽喉   119篇
儿科学   516篇
妇产科学   170篇
基础医学   990篇
口腔科学   231篇
临床医学   646篇
内科学   1945篇
皮肤病学   188篇
神经病学   511篇
特种医学   370篇
外国民族医学   1篇
外科学   1319篇
综合类   269篇
一般理论   7篇
预防医学   521篇
眼科学   285篇
药学   783篇
中国医学   40篇
肿瘤学   602篇
  2023年   68篇
  2022年   142篇
  2021年   288篇
  2020年   159篇
  2019年   195篇
  2018年   254篇
  2017年   189篇
  2016年   226篇
  2015年   237篇
  2014年   329篇
  2013年   444篇
  2012年   600篇
  2011年   653篇
  2010年   415篇
  2009年   315篇
  2008年   491篇
  2007年   505篇
  2006年   438篇
  2005年   407篇
  2004年   345篇
  2003年   297篇
  2002年   281篇
  2001年   195篇
  2000年   207篇
  1999年   182篇
  1998年   89篇
  1997年   51篇
  1996年   49篇
  1995年   52篇
  1994年   47篇
  1993年   32篇
  1992年   93篇
  1991年   88篇
  1990年   82篇
  1989年   98篇
  1988年   80篇
  1987年   67篇
  1986年   59篇
  1985年   69篇
  1984年   63篇
  1983年   59篇
  1982年   36篇
  1979年   47篇
  1978年   30篇
  1977年   32篇
  1976年   31篇
  1974年   38篇
  1973年   38篇
  1972年   29篇
  1969年   35篇
排序方式: 共有9513条查询结果,搜索用时 15 毫秒
1.
2.
Context Withania somnifera (L.) Dunal is traditionally used for treating various ailments, but lacks scientific evaluation.

Objective This study evaluates Withania somnifera (WS) for its effect on platelet activity and inflammatory enzymes.

Materials and methods Aqueous and ethanolic (1:1) leaf extracts were subjected to in vitro indirect haemolytic activity using Naja naja venom, human platelet aggregation was quantified for lipid peroxidation using arachidonic acid (AA) as agonist and 5-lipoxygenase (5-LOX) levels were determined using standard spectrometric assays. Further, molecular docking was performed by the ligand fit method using molegro software package (Molegro ApS, Aarhus, Denmark).

Results The study found that aqueous and ethanol extracts have very negligible effect (15%) with an IC50 value of 13.8?mg/mL on PLA2 from Naja naja venom. Further, extracts of WS also had very little effect (18%) with an IC50 value of 16.6?mg/mL on malondialdehyde (MDA) formation. However, a 65% inhibition of 5-LOX with an IC50 value of 0.92?mg/mL was observed in 1:1 ethanol extracts. The same was evident from SAR model with the active ingredient withaferin A binding predominantly on Phe 77, Tyr 98, Arg 99, Asp 164, Leu 168, Ser 382, Arg 395, Tyr 396 and Tyr 614 with an atomic contact energy value of??128.96 compared to standard phenidone (?103.61). Thus, the current study validates the application of WS for inflammatory diseases.

Conclusion This study reveals the inhibitory potential of W. somnifera on inflammatory enzymes and platelet aggregation. Thus, WS can serve as a newer, safer and affordable medicine for inflammatory diseases.  相似文献   
3.
4.
5.
6.
Molecular characterization of Wuchereria bancrofti is essential to develop suitable anti-filarial drugs and vaccines. We describe here isolation, sequence analysis and cloning of a partial cDNA of an enzyme superoxide dismutase from this parasite. The immunoscreening of a lambda zap W. bancrofti microfilarial (Mf) cDNA library with microfilaremic sera had resulted in the isolation of several seroreactive clones including, WbSOD. This clone contained a 309 bp insert and showed significant nucleotide and deduced amino acid sequence homologies to the superoxide dismutases of other nematode parasites. The antioxidant property of this enzyme may have important contribution in the defense mechanism of the parasite against host immune response.  相似文献   
7.
Brain tissues from 38 patients with a clinical suspicion of encephalitis or encephalopathy were examined by two immunoenzymatic techniques for the detection of arboviral antigen. Group B arboviral antigen was identified in 23 of these tissues. This simple method could be used for the diagnosis of the causal agent of encephalitis.  相似文献   
8.
We thank Coceani and L'Abbate for their comments on our paper.We concur that ‘pathophysiology cannot be inferred fromcoronary lumenography alone’, and this was one of thekey motivations in conducting the present study.  相似文献   
9.
The use of epidemiologic research designs and analytical methods is common in dietetics research. Food and nutrition professionals who seek to perform evidence-based practice or participate in research design, analysis, and communication need skills in the essentials of epidemiology. This is one of a series of monographs on research methodology that addresses these needs and supports the goals of the Board of Editors of the Journal of the American Dietetic Association to further enhance competency and skills. This monograph focuses on statistical approaches for univariate analyses used with the primary observational study designs associated with epidemiology. Tables illustrating the presentation and interpretation of these results are included.  相似文献   
10.
The rising incidence of hepatocellular carcinoma (HCC) in western countries, along with the poor prognosis offered by present-day treatment modalities, makes novel therapies for this disease necessary. Oncolytic herpes simplex viruses (HSV) are replication-competent viruses that are highly effective in the treatment of a wide variety of experimental models of human malignancies. This study seeks to investigate the effectiveness of oncolytic herpes viruses in the treatment of primary HCC cell lines. Sixteen commercially available human HCC cell lines were studied. G207 is an attenuated, replication-competent, oncolytic HSV engineered to selectively replicate within cancer cells. Cell lines were tested for viral sensitivity to G207 and their ability to support viral replication using standard cytotoxicity and viral replication assays. Eleven of 16 cell lines were moderately to highly sensitive to G207 viral oncolysis. HCC cell lines additionally demonstrated the ability to support viral replication in vitro with as high as 800-fold amplification of the administered viral dose observed. G207 is cytotoxic to, and efficiently replicates within, HCC cell lines in vitro. From these data, we suggest that oncolytic HSV therapy may have a role in the treatment of HCC, and in vivo studies are warranted. Presented in part at the 2005 American Hepato-Pancreato-Biliary Association Congress, Hollywood, Florida, April 14–17, 2005. Supported by grants R01CA75461 and R01CA72632 from the National Institutes of Health, and by grant MBC-99366 from the American Cancer Society (Yuman Fong).  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