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   833155篇
  免费   57490篇
  国内免费   1529篇
耳鼻咽喉   10411篇
儿科学   26763篇
妇产科学   20257篇
基础医学   130106篇
口腔科学   23551篇
临床医学   74431篇
内科学   159604篇
皮肤病学   18408篇
神经病学   62043篇
特种医学   30872篇
外国民族医学   96篇
外科学   120552篇
综合类   15405篇
现状与发展   3篇
一般理论   277篇
预防医学   65548篇
眼科学   18535篇
药学   61567篇
  3篇
中国医学   2592篇
肿瘤学   51150篇
  2021年   7401篇
  2019年   7472篇
  2018年   10366篇
  2017年   8261篇
  2016年   9177篇
  2015年   10201篇
  2014年   13875篇
  2013年   20121篇
  2012年   27727篇
  2011年   28809篇
  2010年   16594篇
  2009年   15938篇
  2008年   26530篇
  2007年   28254篇
  2006年   28389篇
  2005年   26641篇
  2004年   25309篇
  2003年   24012篇
  2002年   23022篇
  2001年   40607篇
  2000年   41141篇
  1999年   34211篇
  1998年   9476篇
  1997年   7999篇
  1996年   8356篇
  1995年   7745篇
  1994年   7136篇
  1993年   6585篇
  1992年   25705篇
  1991年   25419篇
  1990年   24705篇
  1989年   24311篇
  1988年   22103篇
  1987年   21229篇
  1986年   20193篇
  1985年   18969篇
  1984年   13863篇
  1983年   11742篇
  1982年   6466篇
  1979年   12417篇
  1978年   8659篇
  1977年   7306篇
  1976年   6954篇
  1975年   7684篇
  1974年   8961篇
  1973年   8605篇
  1972年   8114篇
  1971年   7555篇
  1970年   7220篇
  1969年   6624篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
13.
Pharmaceutical Chemistry Journal - Three extracts were produced from the above-ground part of the meadowsweet Filipendula ulmaria (L.) Maxim. using water, 40% ethanol, and 70% ethanol. Comparative...  相似文献   
14.
Haemophilia is a common cause of genetically inherited bleeding disorders. Pseudotumours occur in 1–2 % of persons with severe forms of haemophilia. These are a result of repeated haemorrhage into soft tissues, subperiosteum or a site of bone fracture with inadequate resorption of the extravasated blood. There are a number of therapeutic alternatives for this dangerous condition: surgical removal, percutaneous management, irradiation, embolization etc. In this case report, we describe the natural history, clinical course and successful surgical management of a patient with haemophilia who presented with a massive pseudotumour. We also briefly review the relevant literature on the various therapeutic modalities that have been implemented in the management of this rare complication. Though surgeons may be averse to operate on haemophiliacs, primary surgical management as done in our case may prove to be the definitive treatment option for such patients.  相似文献   
15.
16.
17.
18.
19.
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   
20.
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   
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