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   1297367篇
  免费   98276篇
  国内免费   1689篇
耳鼻咽喉   16642篇
儿科学   42164篇
妇产科学   35905篇
基础医学   194047篇
口腔科学   35279篇
临床医学   122597篇
内科学   254776篇
皮肤病学   28002篇
神经病学   105441篇
特种医学   47588篇
外国民族医学   269篇
外科学   181941篇
综合类   26152篇
现状与发展   3篇
一般理论   584篇
预防医学   108089篇
眼科学   28523篇
药学   94744篇
  32篇
中国医学   2057篇
肿瘤学   72497篇
  2019年   11032篇
  2018年   14707篇
  2017年   11308篇
  2016年   12286篇
  2015年   14086篇
  2014年   19300篇
  2013年   29255篇
  2012年   39823篇
  2011年   42085篇
  2010年   24365篇
  2009年   23457篇
  2008年   39604篇
  2007年   42219篇
  2006年   41726篇
  2005年   40777篇
  2004年   39077篇
  2003年   37333篇
  2002年   36146篇
  2001年   56454篇
  2000年   57441篇
  1999年   48521篇
  1998年   13713篇
  1997年   12499篇
  1996年   12844篇
  1995年   12134篇
  1994年   11309篇
  1993年   10560篇
  1992年   38448篇
  1991年   37923篇
  1990年   36701篇
  1989年   35473篇
  1988年   32917篇
  1987年   32235篇
  1986年   30758篇
  1985年   28985篇
  1984年   22112篇
  1983年   19376篇
  1982年   11521篇
  1979年   21103篇
  1978年   15526篇
  1977年   12905篇
  1976年   11971篇
  1975年   12926篇
  1974年   15705篇
  1973年   15457篇
  1972年   14591篇
  1971年   13617篇
  1970年   12859篇
  1969年   12141篇
  1968年   11294篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
Naunyn-Schmiedeberg's Archives of Pharmacology - Ochratoxin A (OTA) and aristolochic acid (AA) are toxins that can frequently contaminate cereals and cereals-based products. The present study...  相似文献   
63.
64.
65.
66.
67.
Introduction: Intra-articular (IA) corticosteroid (CS) injections are commonly used in the treatment of osteoarthritis. However, they are rarely utilized in haemophilic arthropathy. In fact, the efficacy of this method in haemophilic arthropathy is frequently discussed and debated in clinical practice.

Aim: To investigate the effectiveness of IA CS injections in patients with painful haemophilic arthropathy.

Methods: A review of the literature on the topic was performed.

Results: In osteoarthritis, reports with a high level of evidence state that the efficacy of IA injections of CS is controversial. In haemophilic arthropathy, some low-level evidence reports seem to indicate that short-term pain alleviation can be achieved.

Conclusions: Considering that pain relief after IA injections of CS is controversial and that the cost of the haematologic treatment required to perform the procedure is high in haemophilic arthropathy, we do not recommend the routine use of CS IS injections in haemophilia. Moreover, point of care (POC) ultrasound (US)-guided injections are not advised, because the injection procedure is so simple that the use of POC-US will unnecessarily prolong the duration of the procedure.  相似文献   

68.
69.
Antibodies are molecules that exhibit diverse conformational changes on different timescales, and there is ongoing interest to better understand the relationship between antibody conformational dynamics and storage stability. Physical stability data for an IgG4 monoclonal antibody (mAb-D) were gathered through traditional forced degradation (temperature and stirring stresses) and accelerated stability studies, in the presence of different additives and solution conditions, as measured by differential scanning calorimetry, size exclusion chromatography, and microflow imaging. The results were correlated with hydrogen exchange mass spectrometry (HX-MS) data gathered for mAb-D in the same formulations. Certain parameters of the HX-MS data, including hydrogen exchange in specific peptide segments in the CH2 domain, were found to correlate with stabilization and destabilization of additives on mAb-D during thermal stress. No such correlations between mAb physical stability and HX-MS readouts were observed under agitation stress. These results demonstrate that HX-MS can be set up as a streamlined methodology (using minimal material and focusing on key peptide segments at key time points) to screen excipients for their ability to physically stabilize mAbs. However, useful correlations between HX-MS and either accelerated or real-time stability studies will be dependent on a particular mAb's degradation pathway(s) and the type of stresses used.  相似文献   
70.
The macrocycle para-sulfonatocalix[8]arene, sCX[8], was examined with 2 antibiotic drugs, ciprofloxacin (CIP) and isoniazid. The drugs were shown to form complexes with sCX[8] using proton nuclear magnetic resonance, thermogravimetric analysis, fluorescence spectroscopy, and molecular modeling. Both drugs form 1:1 hydrated (H2O: 13%-14% w/w) host-guest complexes, with sCX[8] binding around the pyridine ring of isoniazid, and around the piperazine and cyclopropane rings of CIP. From proton nuclear magnetic resonance, the binding constant of isoniazid to sCX[8] was 6.8 (±0.3) × 103 M?1. Addition of 2 equivalents of sCX[8] to CIP resulted in a 58% decrease in fluorescence, and time-resolved fluorescence anisotropy of CIP doubles with sCX[8]. Each drug binds into the cavity of the macrocycle, with binding stabilized via combinations of hydrogen bonding, electrostatic interactions, π-π stacking, and hydrophobic effects. The safety of sCX[8] was examined in vitro with human embryonic kidney 293 cells. The IC50 of sCX[8] was 559 μM, which is a minimum of 5-fold higher than the concentration that would be used in the clinic. The in vitro effect of sCX[8] on the action of CIP was examined on a panel of bacterial lines. The results showed that sCX[8] has no inherent antibiotic activity and had no negative effect on the action of CIP.  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