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   164472篇
  免费   10617篇
  国内免费   586篇
耳鼻咽喉   2177篇
儿科学   5965篇
妇产科学   2775篇
基础医学   20766篇
口腔科学   3468篇
临床医学   15403篇
内科学   33594篇
皮肤病学   3073篇
神经病学   14349篇
特种医学   5460篇
外国民族医学   4篇
外科学   24019篇
综合类   3161篇
现状与发展   1篇
一般理论   186篇
预防医学   13221篇
眼科学   4302篇
药学   12694篇
  3篇
中国医学   521篇
肿瘤学   10533篇
  2023年   750篇
  2022年   1697篇
  2021年   3663篇
  2020年   2109篇
  2019年   2985篇
  2018年   3702篇
  2017年   2791篇
  2016年   3300篇
  2015年   3743篇
  2014年   5403篇
  2013年   7564篇
  2012年   10889篇
  2011年   11332篇
  2010年   6519篇
  2009年   5962篇
  2008年   10050篇
  2007年   10595篇
  2006年   10260篇
  2005年   10325篇
  2004年   9757篇
  2003年   9341篇
  2002年   8724篇
  2001年   1964篇
  2000年   1656篇
  1999年   1835篇
  1998年   1967篇
  1997年   1638篇
  1996年   1389篇
  1995年   1336篇
  1994年   1100篇
  1993年   1092篇
  1992年   1111篇
  1991年   1052篇
  1990年   1036篇
  1989年   965篇
  1988年   871篇
  1987年   804篇
  1986年   796篇
  1985年   910篇
  1984年   1014篇
  1983年   967篇
  1982年   1234篇
  1981年   1130篇
  1980年   1028篇
  1979年   587篇
  1978年   658篇
  1977年   639篇
  1976年   515篇
  1975年   471篇
  1974年   438篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
52.
53.
1. The present study is designed to investigate the brain distribution and plasma pharmacokinetics profiles of chlorogenic acid (CGA) after intranasal administration in Charles–Foster rats to evaluate whether the CGA molecules are transported directly via the nose-to-brain path.

2. The CGA is administered intravenously (IV) and intranasally (IN) at the dose of 10?mg/kg. Further, its concentration in the plasma, cerebrospinal fluid (CSF) and the whole brain is analyzed by HPLC-UV method.

3. The study observes that CGA is rapidly absorbed in plasma with tmax of 1?min similar to IV route after IN administration. The peak plasma concentration and AUC0–24 are higher by 3.5 and 4.0 times respectively in IV administration, compared to IN delivery that represents the significant less systemic exposure of CGA in IN route.

4. However, the concentration of CGA in the brain is 4, 6.5, 5.3, 5.2 and 4.5 times higher at 30, 60, 120, 240 and 360?min, respectively in IN administration compared to IV administration. The exposure of CGA in the brain after IN administration (AUCbrain, IN) was significantly greater (4 times) as compared to the exposure of CGA in the brain (AUCbrain, IV) after IV administration reflecting significant brain uptake of CGA through nasal route. Therefore, IN delivery of CGA can be a promising approach for the treatment of stroke and neurodegenerative disorders.  相似文献   

54.
55.
56.
57.
Background Although prostate cancer is a leading cause of cancer death, its aetiology is not well understood. We aimed to identify novel biochemical factors for prostate cancer incidence and mortality in UK Biobank.Methods A range of cardiovascular, bone, joint, diabetes, renal and liver-related biomarkers were measured in baseline blood samples collected from up to 211,754 men at recruitment and in a subsample 5 years later. Participants were followed-up via linkage to health administrative datasets to identify prostate cancer cases. Hazard ratios (HRs) and 95% confidence intervals were calculated using multivariable-adjusted Cox regression corrected for regression dilution bias. Multiple testing was accounted for by using a false discovery rate controlling procedure.Results After an average follow-up of 6.9 years, 5763 prostate cancer cases and 331 prostate cancer deaths were ascertained. Prostate cancer incidence was positively associated with circulating vitamin D, urea and phosphate concentrations and inversely associated with glucose, total protein and aspartate aminotransferase. Phosphate and cystatin-C were the only biomarkers positively and inversely, respectively, associated with risk in analyses excluding the first 4 years of follow-up. There was little evidence of associations with prostate cancer death.Conclusion We found novel associations of several biomarkers with prostate cancer incidence. Future research will examine associations by tumour characteristics.Subject terms: Predictive markers, Prostate cancer, Risk factors  相似文献   
58.
While once considered as incurable systemic disease, treatment options for liver metastases have increased over the last 30 years and safety has improved dramatically, such that for a selected group of patients the hope of cure can now be offered with radical treatment, and low morbidity interventions can be offered which prolong survival, even in patients with more widely disseminated disease. Advances have been made in selection and surgical technique for liver resection and several adjuncts to resection now exist in the form of portal vein embolization, thermal ablation and targeted drug or radiotherapy delivery options. A natural consequence of these developments has been the delivery of services within fewer specialist units, with the result that later complications of therapy may present to local hospitals, rather than directly to the specialist centres. This article will describe the current common liver-directed therapies and outline the presentation and management of their complications.  相似文献   
59.
Digestive Diseases and Sciences - To determine whether the presence of portal vein thrombosis (PVT) where venous flow within the liver may be altered may delay the diagnosis of HCC and be...  相似文献   
60.
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