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   1942312篇
  免费   151043篇
  国内免费   7329篇
耳鼻咽喉   24815篇
儿科学   62705篇
妇产科学   51523篇
基础医学   277206篇
口腔科学   53845篇
临床医学   175785篇
内科学   389643篇
皮肤病学   45794篇
神经病学   153283篇
特种医学   77382篇
外国民族医学   348篇
外科学   300121篇
综合类   44047篇
现状与发展   4篇
一般理论   626篇
预防医学   150814篇
眼科学   42629篇
药学   139616篇
  8篇
中国医学   4339篇
肿瘤学   106151篇
  2018年   20785篇
  2017年   16175篇
  2016年   18956篇
  2015年   21166篇
  2014年   29331篇
  2013年   43707篇
  2012年   55419篇
  2011年   58901篇
  2010年   36077篇
  2009年   34751篇
  2008年   54609篇
  2007年   58240篇
  2006年   59286篇
  2005年   56686篇
  2004年   54631篇
  2003年   52574篇
  2002年   50264篇
  2001年   93962篇
  2000年   96258篇
  1999年   80187篇
  1998年   23224篇
  1997年   20454篇
  1996年   21362篇
  1995年   21267篇
  1994年   19800篇
  1993年   18453篇
  1992年   65236篇
  1991年   63901篇
  1990年   61733篇
  1989年   59521篇
  1988年   54879篇
  1987年   53735篇
  1986年   50767篇
  1985年   48622篇
  1984年   36636篇
  1983年   30899篇
  1982年   18643篇
  1981年   16772篇
  1980年   15876篇
  1979年   33090篇
  1978年   23820篇
  1977年   20107篇
  1976年   18743篇
  1975年   19892篇
  1974年   23367篇
  1973年   22319篇
  1972年   20757篇
  1971年   19194篇
  1970年   17817篇
  1969年   16607篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
Vestibular function laboratories utilize a multitude of diagnostic instruments to evaluate a dizzy patient. Caloric irrigators, oculomotor stimuli, and rotational chairs produce a stimulus whose accuracy is required for the patient response to be accurate. Careful attention to everything from cleanliness of equipment to threshold adjustments determine on a daily basis if patient data are going to be correct and useful. Instrumentation specifications that change with time such as speed and temperature must periodically be checked using calibrated instruments.  相似文献   
33.
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   
34.
35.
36.
37.
38.
39.
Aging alters bladder functions where a decrease in filling, storage and emptying is observed. These changes cause urinary incontinence, especially in women. The aim of this study is to examine how aging affects the intracellular calcium movements due to agonist-induced contractions in permeabilized female rat bladder. Urinary bladder isolated from young and old female Sprague-Dawley rats were used. Small detrusor strips were permeabilized with β-escin. The contractile responses induced with agonists were compared between young and old groups. Carbachol-induced contractions were decreased in permeabilized detrusor from old rats compared to young group. Heparin and ryanodine decreased carbachol-induced contractions in young rats where only heparin inhibited these contractions in olds. Caffeine-induced contractions but not inositol triphosphate (IP3)-induced contractions were decreased in old group compared to youngs. The cumulative calcium response curves (pCa 8–4) were also decreased in old rats. Carbachol-induced calcium sensitization responses did not alter by age where GTP-β-S and GF-109203X but not Y-27632 inhibited these responses. Carbachol-induced contractions decrease with aging in rat bladder detrusor. It can be postulated as IP3-induced calcium release (IICR) is primarily responsible for the contractions in older rats where the decrease in carbachol contractions in aging may be as a result of a decrease in calcium-induced calcium release (CICR), rather than carbachol-induced calcium sensitization.  相似文献   
40.
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