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   22346篇
  免费   1213篇
  国内免费   252篇
耳鼻咽喉   241篇
儿科学   471篇
妇产科学   665篇
基础医学   2521篇
口腔科学   520篇
临床医学   1652篇
内科学   6021篇
皮肤病学   396篇
神经病学   2446篇
特种医学   878篇
外科学   3608篇
综合类   45篇
一般理论   4篇
预防医学   829篇
眼科学   274篇
药学   1336篇
中国医学   47篇
肿瘤学   1857篇
  2023年   169篇
  2022年   169篇
  2021年   626篇
  2020年   441篇
  2019年   522篇
  2018年   685篇
  2017年   556篇
  2016年   639篇
  2015年   714篇
  2014年   927篇
  2013年   1119篇
  2012年   1766篇
  2011年   1791篇
  2010年   1010篇
  2009年   994篇
  2008年   1619篇
  2007年   1598篇
  2006年   1454篇
  2005年   1383篇
  2004年   1350篇
  2003年   1210篇
  2002年   1067篇
  2001年   143篇
  2000年   110篇
  1999年   149篇
  1998年   145篇
  1997年   119篇
  1996年   130篇
  1995年   125篇
  1994年   84篇
  1993年   95篇
  1992年   91篇
  1991年   68篇
  1990年   64篇
  1989年   77篇
  1988年   49篇
  1987年   64篇
  1986年   52篇
  1985年   37篇
  1984年   55篇
  1983年   48篇
  1982年   35篇
  1981年   41篇
  1980年   42篇
  1979年   19篇
  1978年   14篇
  1977年   20篇
  1976年   14篇
  1974年   14篇
  1971年   9篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
Cardiovascular Drugs and Therapy - Available animal models of acute heart failure (AHF) and their limitations are discussed herein. A novel and preclinically relevant porcine model of decompensated...  相似文献   
2.
In December 2019 a novel coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), started spreading from Wuhan city of Chinese Hubei province and rapidly became a global pandemic. Clinical symptoms of the disease range from paucisymptomatic disease to a much more severe disease. Typical symptoms of the initial phase include fever and cough, with possible progression to acute respiratory distress syndrome. Gastrointestinal manifestations such as diarrhoea, vomiting and abdominal pain are reported in a considerable number of affected individuals and may be due to the SARS-CoV-2 tropism for the peptidase angiotensin receptor 2. The intestinal homeostasis and microenvironment appear to play a major role in the pathogenesis of COVID-19 and in the enhancement of the systemic inflammatory responses. Long-term consequences of COVID-19 include respiratory disturbances and other disabling manifestations, such as fatigue and psychological impairment. To date, there is a paucity of data on the gastrointestinal sequelae of SARS-CoV-2 infection. Since COVID-19 can directly or indirectly affect the gut physiology in different ways, it is plausible that functional bowel diseases may occur after the recovery because of potential pathophysiological alterations (dysbiosis, disruption of the intestinal barrier, mucosal microinflammation, post-infectious states, immune dysregulation and psychological stress). In this review we speculate that COVID-19 can trigger irritable bowel syndrome and we discuss the potential mechanisms.  相似文献   
3.
4.
5.
6.
The recognition that neurogenesis does not stop with adolescence has spun off research towards the reduction of brain disorders by enhancing brain regeneration. Adult neurogenesis is one of the tougher problems of developmental biology as it requires the generation of complex intracellular and pericellular anatomies, amidst the danger of neuroinflammation. We here review how a multitude of regulatory pathways optimized for early neurogenesis has to be revamped into a new choreography of time dependencies. Distinct pathways need to be regulated, ranging from neural growth factor induced differentiation to mitochondrial bioenergetics, reactive oxygen metabolism, and apoptosis. Requiring much Gibbs energy consumption, brain depends on aerobic energy metabolism, hence on mitochondrial activity. Mitochondrial fission and fusion, movement and perhaps even mitoptosis, thereby come into play. All these network processes are interlinked and involve a plethora of molecules. We recommend a deep thinking approach to adult neurobiology.  相似文献   
7.
Introduction: Allergic rhinitis (AR) is the most common allergic disease, and it has a relevant impact on the quality of life of the patient. Treatment of AR includes a combination of strategies of proven efficacy and effectiveness; however, a relevant proportion of patients remain uncontrolled.

Areas covered: This review article summarizes emerging therapeutic approaches to AR; these approaches include nasal sprays, oral drugs, alternative allergen immunotherapy administration routes, and biologic agents.

Expert opinion: The agents discussed require further clinical trials to prove their efficacy in the treatment of AR. Some of these agents, in particular, allergen immunotherapies and biologics, have the potential to form crucial precision medicine approaches to AR. Those that prove their efficacy in clinical trials must also be evaluated from a pharmacoeconomic perspective, possibly in real-life studies; this will define which therapeutic strategies achieve the most convenient and cost-effective ratio, thus yielding a novel opportunity for the most severe and previously treatment-resistant allergic patients.  相似文献   

8.

Background

In colorectal cancer liver metastases (CRCLM), bevacizumab-based neoadjuvant strategies provide increased pathologic response. We aimed at assessing the activity of perioperative capecitabine, oxaliplatin, irinotecan, and bevacizumab (COI-B regimen) in patients with potentially resectable CRCLM, and investigating biomarkers for early prediction of pathologic response.

Patients and Methods

This was a single-center phase II study enrolling patients with liver-limited, borderline resectable disease and/or high-risk features. Patients received 5 preoperative and 4 postoperative cycles of biweekly COI-B (irinotecan 180 mg/m2 and bevacizumab 5 mg/Kg on day 1, oxaliplatin 85 mg/m2 on day 2, and capecitabine 1000 mg/m2 twice a day on days 2 to 6). The primary endpoint was pathologic response rate in the intention-to-treat population. A Simon 2-stage design was adopted to detect an increase from 30% to 50% with a power of 90%. Dynamic imaging biomarkers (early tumor shrinkage [ETS], deepness of response, maximum standardized uptake volume [SUVmax]/regression index) and next generation sequencing data were explored as surrogates.

Results

From June 2013 to March 2017, 46 patients were enrolled. Pathologic response was achieved in 63% patients (endpoint met), and responders achieved significantly better survival outcomes with respect to non-responders. The most frequent grade 3/4 adverse events were diarrhea and neutropenia (8.7%) in the preoperative phase and thromboembolic events (5.9%) in the postoperative phase. ETS and lower SUV-2 were significantly associated with pathologic response.

Conclusion

The COI-B regimen is a feasible and highly active perioperative strategy in patients with molecularly unselected, potentially resectable CRCLM. ETS and SUV-2 have a promising role as imaging-based biomarkers for pathologic response.  相似文献   
9.
10.
Medicine, Health Care and Philosophy - Both a significant body of literature and the case study presented here show that digital knowledge repositories struggle to attract the needed level of data...  相似文献   
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