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   2114篇
  免费   126篇
  国内免费   9篇
耳鼻咽喉   4篇
儿科学   106篇
妇产科学   64篇
基础医学   234篇
口腔科学   29篇
临床医学   162篇
内科学   412篇
皮肤病学   33篇
神经病学   97篇
特种医学   65篇
外科学   397篇
综合类   45篇
预防医学   73篇
眼科学   155篇
药学   186篇
中国医学   18篇
肿瘤学   169篇
  2023年   11篇
  2022年   33篇
  2021年   81篇
  2020年   49篇
  2019年   65篇
  2018年   93篇
  2017年   52篇
  2016年   78篇
  2015年   71篇
  2014年   104篇
  2013年   134篇
  2012年   160篇
  2011年   191篇
  2010年   91篇
  2009年   102篇
  2008年   148篇
  2007年   153篇
  2006年   133篇
  2005年   121篇
  2004年   101篇
  2003年   81篇
  2002年   52篇
  2001年   22篇
  2000年   10篇
  1999年   18篇
  1998年   10篇
  1997年   11篇
  1996年   10篇
  1995年   3篇
  1994年   11篇
  1993年   3篇
  1992年   6篇
  1991年   6篇
  1990年   1篇
  1989年   5篇
  1988年   5篇
  1987年   3篇
  1986年   3篇
  1985年   2篇
  1984年   4篇
  1982年   1篇
  1981年   3篇
  1980年   2篇
  1979年   1篇
  1972年   1篇
  1960年   1篇
  1934年   1篇
  1928年   1篇
  1909年   1篇
排序方式: 共有2249条查询结果,搜索用时 15 毫秒
71.
72.
Extracellular lysophosphatidate(LPA) is a potent bioactive lipid that signals through six G-protein-coupled receptors.This signaling is required for embryogenesis,tissue repair and remodeling processes.LPA is produced from circulating lysophosphatidylcholine by autotaxin(ATX),and is degraded outside cells by a family of three enzymes called the lipid phosphate phosphatases(LPPs).In many pathological conditions,particularly in cancers,LPA concentrations are increased due to high ATX expression and low LPP activity.In cancers,LPA signaling drives tumor growth,angiogenesis,metastasis,resistance to chemotherapy and decreased efficacy of radiotherapy.Hence,targeting the ATX-LPA-LPP axis is an attractive strategy for introducing novel adjuvant therapeutic options.In this review,we will summarize current progress in targeting the ATX-LPA-LPP axis with inhibitors of autotaxin activity,LPA receptor antagonists,LPA monoclonal antibodies,and increasing low LPP expression.Some of these agents are already in clinical trials and have applications beyond cancer,including chronic inflammatory diseases.  相似文献   
73.
Strains of Enterococcus faecium express a cell wall-anchored protein, Acm, which mediates adherence to collagen. Here, we (i) identify the minimal and high-affinity binding subsegments of Acm and (ii) show that anti-Acm immunoglobulin Gs (IgGs) purified against these subsegments reduced E. faecium TX2535 strain collagen adherence up to 73 and 50%, respectively, significantly more than the total IgGs against the full-length Acm A domain (28%) (P < 0.0001). Blocking Acm adherence with functional subsegment-specific antibodies raises the possibility of their use as therapeutic or prophylactic agents.  相似文献   
74.
Cancer of breast and cervix reign supreme among the fatal diseases in women globally. Interestingly the ovarian cancer has the highest mortality rate. This is attributed to its late clinical presentation and delayed diagnosis. The expression of p53 throws light on the prognosis of ovarian tumors. The surface epithelial tumors, especially the serous cystadenocarcinoma and non Hodgkin lymphoma of ovary where in the expression p53 was high compared to the benign and borderline tumors. Further the expression of p53 in tumors arising from germinal cells, sex-cord stromal cells are observed to be very low. The expression of p53 and its correlation to the morphology enhances the prognostic significance.  相似文献   
75.
A 24-year-old female underwent small incision lenticule extraction (SMILE) for myopic astigmatism OU. In the left eye, cap-lenticular adhesion along with tearing of the cap occurred, resulting in a gaped incision and transverse striae involving the visual axis on the first post op day. Uncorrected distance visual acuity (UDVA) was 20/32. The case was managed with interface wash and stretching of the cap, in order to iron out the striae. Post intervention, the UDVA improved to 20/20, striae resolved, and interface remained clear through a follow-up of nine months, suggesting that cap striae in SMILE may be similarly managed as the flap striae in laser-assisted in situ keratomileusis (LASIK), resulting in satisfactory visual outcomes.  相似文献   
76.
77.
A library of 2,5-disubstituted 1,3,4-oxadiazole derivatives of (E)-2-aryl-5-(3,4,5-trimethoxystyryl)-1,3,4-oxadiazoles 4(ao) and (E)-2-aryl-5-(2-benzo[d][1,3]dioxol-5-yl)vinyl)-1,3,4-oxadiazoles 5(aq) were synthesized and evaluated for their in vitro acetylcholinesterase (AChE) inhibitory activity. All the synthesized compounds exhibited moderate to good inhibitory activity toward the AChE enzyme. Among the oxadiazole derivatives examined, compounds 4a, 4g, 5c, and 5m (IC50 values of 24.89, 13.72, 37.65, and 19.63 μM, respectively) were found to be promising inhibitors of AChE. Molecular protein–ligand docking studies were examined for these compounds using GOLD docking software and their binding conformations were determined and the simultaneous interactions mode was also established for the potent derivatives.  相似文献   
78.
Bone formation is reported to initiate in osteocytes by mechanotransduction due to dynamic loading of bone. The first step towards this is to characterize the dynamic strain fields in the overall bone. Here, the previously developed mouse forearm ulna‐radius model, subjected to static loading, has been further enhanced by incorporating a loading cap and applying a cyclic dynamic load to more closely approximate experimental biological conditions. This study also incorporates data obtained from strain gauging both the ulna and radius simultaneously. Based on separate experiments, the elastic modulus of the ulna and radius were determined to be 13.8 and 9.9 GPa, respectively. Another novel aspect of the numerical model is the inclusion of the interosseous membrane in the FE model with membrane stiffness ranging from 5–15 N/mm that have been found to give strain values closer to that from the experiments. Interestingly, the inclusion of the interosseous membrane helped to equalize the peak strain magnitudes in the ulna and radius (~1800 at 2 N load and ~3200 at 3.5 N), which was also observed experimentally. This model represents a significant advance towards being able to simulate through FE analysis the strain fields generated in vivo upon mechanical loading of the mouse forearm. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:1580–1588, 2014.  相似文献   
79.
80.
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