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   3703014篇
  免费   263626篇
  国内免费   9738篇
耳鼻咽喉   50354篇
儿科学   124021篇
妇产科学   102953篇
基础医学   518860篇
口腔科学   105456篇
临床医学   337938篇
内科学   718041篇
皮肤病学   87956篇
神经病学   297490篇
特种医学   143438篇
外国民族医学   1024篇
外科学   555693篇
综合类   78341篇
现状与发展   8篇
一般理论   1392篇
预防医学   284663篇
眼科学   86235篇
药学   271315篇
  14篇
中国医学   7803篇
肿瘤学   203383篇
  2019年   28692篇
  2018年   43562篇
  2017年   34131篇
  2016年   37805篇
  2015年   43675篇
  2014年   58537篇
  2013年   85314篇
  2012年   118624篇
  2011年   121535篇
  2010年   72414篇
  2009年   69879篇
  2008年   111606篇
  2007年   119184篇
  2006年   120929篇
  2005年   122411篇
  2004年   119386篇
  2003年   111443篇
  2002年   104043篇
  2001年   176893篇
  2000年   180038篇
  1999年   152348篇
  1998年   40982篇
  1997年   35598篇
  1996年   35688篇
  1995年   36766篇
  1994年   33637篇
  1993年   31481篇
  1992年   119700篇
  1991年   116007篇
  1990年   112521篇
  1989年   108746篇
  1988年   99515篇
  1987年   97547篇
  1986年   91656篇
  1985年   87315篇
  1984年   64866篇
  1983年   55001篇
  1982年   31862篇
  1981年   28296篇
  1979年   57876篇
  1978年   40430篇
  1977年   34300篇
  1976年   31874篇
  1975年   34282篇
  1974年   41076篇
  1973年   39151篇
  1972年   36741篇
  1971年   34202篇
  1970年   31597篇
  1969年   30273篇
排序方式: 共有10000条查询结果,搜索用时 61 毫秒
1.
2.
Modified-release opioids are often prescribed for the management of moderate to severe acute pain following total hip and knee arthroplasty, despite recommendations against their use due to increasing concerns regarding harm. The primary objective of this multicentre study was to examine the impact of modified-release opioid use on the incidence of opioid-related adverse events compared with immediate-release opioid use, among adult inpatients following total hip or knee arthroplasty. Data for total hip and knee arthroplasty inpatients receiving an opioid analgesic for postoperative analgesia during hospitalisation were collected from electronic medical records of three tertiary metropolitan hospitals in Australia. The primary outcome was the incidence of opioid-related adverse events during hospital admission. Patients who received modified with or without immediate-release opioids were matched to those receiving immediate-release opioids only (1:1) using nearest neighbour propensity score matching with patient and clinical characteristics as covariates. This included total opioid dose received. In the matched cohorts, patients given modified-release opioids (n = 347) experienced a higher incidence of opioid-related adverse events overall, compared with those given immediate-release opioids only (20.5%, 71/347 vs. 12.7%, 44/347; difference in proportions 7.8% [95%CI 2.3–13.3%]). Modified-release opioid use was associated with an increased risk of harm when used for acute pain during hospitalisation after total hip or knee arthroplasty.  相似文献   
3.
4.
Renal cell cancer (RCC) represents 2%-3% of all adulthood cancers and is the most common malignant neoplasm of the kidney (90%). In the mid-nineties of the last century, the standard of treatment for patients with metastatic RCC was cytokines. Sunititib and pazopanib were registered in 2007 and 2009, respectively, and have since been the standard first-line treatment for metastatic clear cell RCC (mccRCC). Renal cell cancer is a highly immunogenic tumor with tumor infiltrating cells, including CD8+ T lymphocytes, dendritic cells, natural killer cells (NK) and macrophages. This observation led to the design of new clinical trials in which patients were treated with immunotherapy. With the growing evidence that proangiogenic factors can have immunomodulatory effects on the host’s immune system, the idea of combining angiogenic drugs with immunotherapy has emerged, and new clinical trials have been designed. In the last few years, several therapeutic options have been approved [immunotherapy and immunotherapy/tyrosine kinase inhibitors (TKI)] for the first-line treatment of mccRCC. Nivolumab/ipilimumab is approved for the treatment of patients with intermediate and poor prognoses. Several checkpoint inhibitors (pembrolizumab, nivolumab, avelumab) in combination with TKI (axitinib, lenvatinib, cabozantinib) are approved for the treatment of patients regardless of their International mRCC Database Consortium prognostic group and PD-L1 expression. There is no specific and ideal biomarker that could help in selecting the ideal patient for the appropriate first-line treatment.  相似文献   
5.
Neuroscience and Behavioral Physiology - We present here results from analysis of the formation of brain bioelectrical activity in children and adolescents living in the northern region of Russia...  相似文献   
6.
7.
The aim of this safety study in mice was to determine in vivo toxicity and biodistribution potential of a single and multiple doses of L-glutamic acid-g-p(HEMA) polymeric nanoparticles as a drug delivery system. The single dose did not cause any lethal effect, and its acute oral LD50 was >2.000 mg/kg body weight (bw). Multiple doses (25, 50, or 100 mg/kg bw) given over 28 days resulted in no significant differences in body and relative organ weights compared to control. These results are supported by biochemical and histological findings. Moreover, nanoparticle exposure did not result in statistically significant differences in micronucleus counts in bone marrow cells compared to control. Nanoparticle distribution was time-dependent, and they reached the organs and even bone marrow by hour 6, as established by ex vivo imaging with the IVIS® spectrum imaging system. In conclusion, L-glutamic acid-g-p(HEMA) polymeric nanoparticles appear biocompatible and have a potential use as a drug delivery system.KEY WORDS: biocompatibility, blood biochemistry, genotoxicity, histology, in vivo toxicity, micronucleus test, polymers  相似文献   
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