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   88094篇
  免费   45577篇
  国内免费   76篇
耳鼻咽喉   1607篇
儿科学   4436篇
妇产科学   775篇
基础医学   17457篇
口腔科学   5497篇
临床医学   14168篇
内科学   25527篇
皮肤病学   7765篇
神经病学   14735篇
特种医学   2908篇
外科学   16103篇
综合类   96篇
一般理论   26篇
预防医学   5231篇
眼科学   1661篇
药学   6454篇
中国医学   1045篇
肿瘤学   8256篇
  2023年   132篇
  2022年   80篇
  2021年   1515篇
  2020年   5242篇
  2019年   11047篇
  2018年   10364篇
  2017年   11682篇
  2016年   12378篇
  2015年   12259篇
  2014年   12240篇
  2013年   12908篇
  2012年   5003篇
  2011年   4992篇
  2010年   9393篇
  2009年   5714篇
  2008年   2849篇
  2007年   1731篇
  2006年   1717篇
  2005年   1447篇
  2004年   1409篇
  2003年   1222篇
  2002年   1185篇
  2001年   920篇
  2000年   816篇
  1999年   425篇
  1998年   206篇
  1997年   138篇
  1996年   138篇
  1995年   148篇
  1994年   146篇
  1993年   121篇
  1992年   336篇
  1991年   343篇
  1990年   332篇
  1989年   274篇
  1988年   250篇
  1987年   287篇
  1986年   268篇
  1985年   216篇
  1984年   212篇
  1983年   195篇
  1982年   115篇
  1981年   90篇
  1979年   128篇
  1978年   96篇
  1977年   83篇
  1975年   77篇
  1974年   78篇
  1973年   82篇
  1970年   74篇
排序方式: 共有10000条查询结果,搜索用时 140 毫秒
1.
2.
ObjectiveSpinal cord stimulation (SCS) is an effective treatment in failed back surgery syndrome (FBSS). We studied the effect of preimplantation opioid use on SCS outcome and the effect of SCS on opioid use during a two-year follow-up period.Materials and methodsThe study cohort included 211 consecutive FBSS patients who underwent an SCS trial from January 1997 to March 2014. Participants were divided into groups, which were as follows: 1) SCS trial only (n = 47), 2) successful SCS (implanted and in use throughout the two-year follow-up period, n = 131), and 3) unsuccessful SCS (implanted but later explanted or revised due to inadequate pain relief, n = 29). Patients who underwent explantation for other reasons (n = 4) were excluded. Opioid purchase data from January 1995 to March 2016 were retrieved from national registries.ResultsHigher preimplantation opioid doses associated with unsuccessful SCS (ROC: AUC = 0.66, p = 0.009), with 35 morphine milligram equivalents (MME)/day as the optimal cutoff value. All opioids were discontinued in 23% of patients with successful SCS, but in none of the patients with unsuccessful SCS (p = 0.004). Strong opioids were discontinued in 39% of patients with successful SCS, but in none of the patients with unsuccessful SCS (p = 0.04). Mean opioid dose escalated from 18 ± 4 MME/day to 36 ± 6 MME/day with successful SCS and from 22 ± 8 MME/day to 82 ± 21 MME/day with unsuccessful SCS (p < 0.001).ConclusionsHigher preimplantation opioid doses were associated with SCS failure, suggesting the need for opioid tapering before implantation. With continuous SCS therapy and no explantation or revision due to inadequate pain relief, 39% of FBSS patients discontinued strong opioids, and 23% discontinued all opioids. This indicates that SCS should be considered before detrimental dose escalation.  相似文献   
3.
A 70‐year‐old man with a history of coronary artery bypass grafting 15 years back and arteriovenous (AV) fistula creation in the left arm 1 month back presented with acute coronary syndrome (ACS). He had not received dialysis before his referral. We felt the most likely etiology for these complaints was increased cardiac oxygen demand from an increased cardiac output related to the newly formed left AV fistula. Coronary angiography was done to detect any significant stenosis in the native or grafted vessels. This revealed that the left subclavian artery was totally occluded in the ostioproximal segment and the coronary arteries did not have occlusions to explain the ACS setting. CT angiography confirmed the angiographic findings of the totally occluded left subclavian artery followed by a well‐developed and patent left internal mammary artery to left anterior descending artery. This led to the consideration of a steal syndrome from the coronary artery by the subclavian artery distal to the occlusion. A successful percutaneous endovascular intervention on the left subclavian artery occlusion was performed. Subsequently, the patient became asymptomatic and experienced a dramatic increase in left ventricular ejection fraction.  相似文献   
4.
5.
Karyotypic analysis at time of diagnosis has an important value in determining initial response to treatment, remission duration and overall survival (OS) in acute myeloid leukemia (AML). Less is known about its value before allogeneic hematopoietic cell transplantation (allo‐HCT) in patients transplanted with active disease, either relapsed or primary refractory (Rel‐Ref) AML. We explored the impact of cytogenetic risk (stratification according to MRC‐UK) in 2089 patients with either Ref (n = 972) or Rel AML (n = 1117) transplanted during the period 2000‐2017. Overall, 154 patients had a favorable risk, 1283 had an intermediate risk and 652 had an adverse cytogenetic risk. Median follow‐up was 49 months. Compared to the favorable risk group, intermediate and adverse risk patients were associated with worse leukemia‐free survival and OS and also with a higher incidence of relapse. In a subgroup analysis of patients in the intermediate risk group harboring Fms‐like tyrosine kinase 3‐internal tandem duplication (FLT3‐ITD), this remained an important prognostic factor, being associated with worse outcomes. When analyzing patients according to the intensity of the conditioning regimen, no differences were observed for the main transplant outcomes. In conclusion, in patients diagnosed with AML and transplanted with active disease, karyotype remains an important prognostic factor, allowing splitting patients into different risk groups according to their cytogenetics. Similarly, FLT3‐ITD mutation also remains a negative prognostic factor in this population.  相似文献   
6.
7.
8.
9.
10.
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