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   7993篇
  免费   771篇
  国内免费   35篇
耳鼻咽喉   77篇
儿科学   454篇
妇产科学   152篇
基础医学   1018篇
口腔科学   101篇
临床医学   835篇
内科学   1596篇
皮肤病学   181篇
神经病学   591篇
特种医学   528篇
外科学   1283篇
综合类   217篇
一般理论   2篇
预防医学   599篇
眼科学   148篇
药学   505篇
  2篇
中国医学   6篇
肿瘤学   504篇
  2021年   108篇
  2020年   81篇
  2019年   125篇
  2018年   153篇
  2017年   112篇
  2016年   103篇
  2015年   149篇
  2014年   201篇
  2013年   241篇
  2012年   342篇
  2011年   386篇
  2010年   253篇
  2009年   196篇
  2008年   364篇
  2007年   357篇
  2006年   356篇
  2005年   368篇
  2004年   325篇
  2003年   310篇
  2002年   293篇
  2001年   233篇
  2000年   247篇
  1999年   191篇
  1998年   134篇
  1997年   138篇
  1996年   173篇
  1995年   132篇
  1994年   94篇
  1993年   125篇
  1992年   185篇
  1991年   183篇
  1990年   160篇
  1989年   163篇
  1988年   164篇
  1987年   159篇
  1986年   136篇
  1985年   159篇
  1984年   92篇
  1983年   92篇
  1982年   69篇
  1981年   52篇
  1980年   42篇
  1979年   60篇
  1978年   47篇
  1977年   59篇
  1976年   58篇
  1975年   56篇
  1974年   42篇
  1973年   40篇
  1971年   44篇
排序方式: 共有8799条查询结果,搜索用时 15 毫秒
151.
Adherence to non-vitamin-K oral anticoagulants (NOACs) may be lower than to vitamin K antagonists because NOACs do not require routine monitoring. We assessed the impact of an educational program on adherence and persistence with apixaban in patients with non-valvular atrial fibrillation (NVAF). Patients with NVAF eligible for NOACs with one or more stroke risk factor (prior stroke/transient ischemic attack, age ≥ 75 years, hypertension, diabetes, or symptomatic heart failure) were randomized (1:1) to standard of care (SOC) or SOC with additional educational (information booklet, reminder tools, virtual clinic access). The primary outcome was adherence to apixaban (2.5 or 5 mg twice daily) at 24 weeks. Patients receiving the educational program were re-randomized (1:1) to continue the program for 24 further weeks or to switch to secondary SOC. Implementation adherence and persistence were reassessed at 48 weeks. In total, 1162 patients were randomized (SOC, 583; educational program, 579). Mean implementation adherence ± standard deviation (SD) at 24 weeks was 91.6% ± 17.1 for SOC and 91.9% ± 16.1 for the educational program arm; results did not differ significantly between groups at any time-point. At 48 weeks, implementation adherence was 90.4% ± 18.0, 90.1% ± 18.6, and 89.3% ± 18.1 for continued educational program, SOC, and secondary SOC, respectively; and corresponding persistence was 86.1% (95% confidence interval [CI] 81.3–89.7), 85.2% (95% CI 81.5–88.2), and 87.8% (95% CI 83.4–91.1). Serious adverse events were similar across groups. High implementation adherence and persistence with apixaban were observed in patients with NVAF receiving apixaban. The educational program did not show additional benefits. This study is registered at ClinicalTrials.gov [NCT01884350].  相似文献   
152.
The endovenous revolution has accelerated the development of new techniques and devices for the treatment of varicose veins. The ClariVein® mechanochemical ablation device offers tumescentless treatment with a rotating ablation tip that can theoretically become stuck in tissue. We present the first report of retrograde stripping of the small saphenous vein without anaesthesia following attempted use of the ClariVein® device, without adverse sequelae.  相似文献   
153.
Most secretory proteins, including antithrombin (AT), aresynthesized with a signal peptide, which is cleaved before the mature protein is exported from the cell. The signal peptide is important inthe process whereby nascent protein is recognized as requiring subsequent modification within the endoplasmic reticulum (ER). We haveidentified a novel mutation, 2436TC L(-10)P, which affects the central hydrophobic domain of the AT signal peptide, in a probandpresenting with venous thrombotic disease and type I AT deficiency. Weinvestigated the basis of the phenotype by examining expression inmammalian cells of a range of variant AT cDNAs with mutations affectingthe -10 residue. Glycosylated AT was secreted from COS-7 cellstransfected with wild-type AT, -10L deletion, -10V or -10M variants,but not variants with P, T, R, or G at -10. Cell-free expression ofwild-type and variant AT cDNAs was then performed in the presence ofcanine pancreatic microsomes, as a substitute for ER. Variant ATproteins with P, T, R, or G at residue -10 did not undergoposttranslational glycosylation, and their susceptibility to trypsindigestion suggested they had not been translocated into microsomes. Ourresults suggest that the ability of AT signal peptide to direct theprotein to ER for cotranslational processing events appears to becritically dependent on maintaining the hydrophobic nature of theregion including residue -10. The investigations have defined impairedcotranslational processing as a hitherto unrecognized cause ofhereditary AT deficiency.  相似文献   
154.
155.
Eosinophils stimulate fibroblast DNA synthesis   总被引:9,自引:0,他引:9  
Pincus  SH; Ramesh  KS; Wyler  DJ 《Blood》1987,70(2):572-574
Fibrosis complicates a number of chronic inflammatory diseases and occurs in some conditions following chronic hypereosinophilic syndromes. We assessed whether eosinophils might be a source of fibrogenic factors. Extracts of human and guinea pig cell populations enriched for eosinophils contained substances that stimulated tritiated thymidine incorporation by human fibroblasts. Supernatants derived from resting eosinophils and extracts prepared from eosinophil granules also contained fibrogenic factors. Our findings demonstrate a new potential role for eosinophils and suggest a causal relationship between tissue eosinophilia and scar formation in certain parasitic conditions.  相似文献   
156.
157.
158.
159.
160.
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