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   2748篇
  免费   126篇
  国内免费   25篇
耳鼻咽喉   12篇
儿科学   72篇
妇产科学   72篇
基础医学   292篇
口腔科学   127篇
临床医学   254篇
内科学   660篇
皮肤病学   44篇
神经病学   158篇
特种医学   366篇
外科学   273篇
综合类   17篇
预防医学   97篇
眼科学   16篇
药学   179篇
中国医学   4篇
肿瘤学   256篇
  2022年   20篇
  2021年   37篇
  2020年   32篇
  2019年   40篇
  2018年   54篇
  2017年   28篇
  2016年   34篇
  2015年   47篇
  2014年   62篇
  2013年   78篇
  2012年   119篇
  2011年   119篇
  2010年   59篇
  2009年   98篇
  2008年   77篇
  2007年   99篇
  2006年   108篇
  2005年   134篇
  2004年   137篇
  2003年   86篇
  2002年   72篇
  2001年   80篇
  2000年   79篇
  1999年   62篇
  1998年   70篇
  1997年   58篇
  1996年   78篇
  1995年   75篇
  1994年   44篇
  1993年   48篇
  1992年   41篇
  1991年   42篇
  1990年   60篇
  1989年   71篇
  1988年   68篇
  1987年   56篇
  1986年   49篇
  1985年   56篇
  1984年   38篇
  1983年   30篇
  1982年   34篇
  1981年   29篇
  1980年   16篇
  1979年   13篇
  1978年   11篇
  1977年   34篇
  1976年   21篇
  1975年   18篇
  1971年   11篇
  1969年   9篇
排序方式: 共有2899条查询结果,搜索用时 15 毫秒
11.
Inflammatory biomarkers in blood of patients with acute brain ischemia   总被引:11,自引:0,他引:11  
Although many failed surrogate markers are provided in the literature, inflammation may contribute to the outcome of ischemic stroke. In 50 consecutive patients with acute ischemic stroke, in the absence of symptoms and signs of concomitant infection, we evaluated a panel of biomarkers reported to be variably associated with brain ischemia, and correlate their serum level with the brain lesion volume and clinical outcome. Infarct size was calculated on computed tomography (CT) scans by means of the Cavalieri's method. Neurological impairment was scored by using the Glasgow Coma Scale, Glasgow Outcome Scale and National Institutes of Health (NIH) scales at stroke onset and 3-month follow-up. Some markers showed a direct significant correlation with both initial and final NIH scale and with infarct size, particularly tumor necrosis factor alpha (TNF-alpha) (P=0.002), intercellular adhesion molecule-1 (P<0.01) and matrix metalloproteinase-2/9 (P=0.001). In contrast to previous reports, interleukin-6 (IL-6) serum level showed a significant inverse correlation with both final neurological impairment and infarct size (P<0.001). This novel finding allows us suggesting that IL-6, in the context of a complex pro-inflammatory network occurring during stroke, is associated with neuroprotection rather than neurotoxicity in patients with ischemic brain injury.  相似文献   
12.
13.
Platelet adhesion to collagen under flow conditions was studied in 18 patients with lupus anticoagulant, seven of which showed a prolonged bleeding time in the presence of a normal platelet count. The effect of patient plasma, IgG and purified anticardiolipin antibodies on platelet adhesion was also examined. We found a significant reduction of platelet adhesion in patients with lupus anticoagulant, which was more evident in patients with prolonged bleeding time. This platelet adhesion defect could be attributed to a plasma factor. In fact, patients' platelets regained normal adhesion when mixed with normal plasma, whereas controls' platelets showed abnormal adhesion in the presence of patient plasma. A causative role of antiphospholipid antibodies was demonstrated in experiments using purified immunoglobulins and anticardiolipin antibodies.  相似文献   
14.
Folate deficiency is a common unpleasant secondary effect of anticonvulsant therapy. In order to contribute to the knowledge of biochemical mechanisms leading to this condition, the effects of two i.p. high doses of phenobarbitone administered to the rat (acute treatment) on the distribution of hepatic folate derivatives have been studied. A significant decrease of unsubstituted tetrahydro- and dihydropteroylpentaglutamates and 5,10-methylenetetrahydropentaglutamates was observed. The hypothesis that a lower availability of NADPH, which is utilized for hydroxylation reactions in phenobarbitone metabolism, may limit folate reduction is proposed.  相似文献   
15.
16.
Marchetti  B. 《Acta endoscopica》2005,35(2):525-528
Acta Endoscopica - Les incidents déclarés à l’AFSSAPS concernant les dispositifs de nutrition par gastrostomie ne correspondent pas pour la plupart d’entre eux à de...  相似文献   
17.
OBJECTIVE: The aim was to establish the potential efficacy, tolerabilityand side-effect profile of electromagnetic therapy as an adjunctto conventional dressings in the treatment of venous leg ulcers. METHOD: A prospective, randomized, double blind controlled clinicaltrial was carried out in a dedicated leg ulcer clinic basedin one urban general practice. Nineteen patients with leg ulcersof confirmed venous aetiology were assessed. The main outcomemeasures were rate and scale of venous leg ulcer healing, changesin patient-reported pain levels, quality of life, degree ofmobility, side effect profile and acceptability to patientsand staff. RESULTS: Sixty-eight per cent of patients attending this dedicated clinicachieved improvements in the size of their ulcer (4, 21%, healedfully) and in reduced pain levels (P < 0.05) during the trial,despite the chronicity of ulcer histories. Patients treatedwith electromagnetic therapy at 800 Hz were found at day 50to have significantly greater healing (P < 0.05) and paincontrol (P < 0.05) than placebo therapy or treatment with600 Hz. All patients reported improved mobility at the end ofthe study. The electromagnetic therapy was well tolerated bypatients, with no differences between groups in reporting adverseevents, and proved acceptable to staff. CONCLUSION: Despite the small numbers in this pilot study, electromagnetictherapy provided significant gains in the healing of venousleg ulcers and reduction in pain. Keywords. Electromagnetic therapy, RCT, leg ulcers, primary care.  相似文献   
18.
Bile duct calculi in patients with primary sclerosing cholangitis   总被引:1,自引:0,他引:1  
  相似文献   
19.
20.
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