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   184986篇
  免费   10795篇
  国内免费   809篇
耳鼻咽喉   1974篇
儿科学   5235篇
妇产科学   4140篇
基础医学   25961篇
口腔科学   6759篇
临床医学   15817篇
内科学   43087篇
皮肤病学   4472篇
神经病学   17530篇
特种医学   4429篇
外国民族医学   2篇
外科学   20187篇
综合类   768篇
一般理论   78篇
预防医学   17300篇
眼科学   3146篇
药学   12801篇
中国医学   682篇
肿瘤学   12222篇
  2024年   170篇
  2023年   1494篇
  2022年   2486篇
  2021年   4862篇
  2020年   3028篇
  2019年   4406篇
  2018年   5862篇
  2017年   4173篇
  2016年   4669篇
  2015年   5517篇
  2014年   6682篇
  2013年   8972篇
  2012年   15535篇
  2011年   16049篇
  2010年   8149篇
  2009年   6581篇
  2008年   13112篇
  2007年   13305篇
  2006年   12660篇
  2005年   12084篇
  2004年   10895篇
  2003年   9929篇
  2002年   9159篇
  2001年   2271篇
  2000年   2613篇
  1999年   1753篇
  1998年   1100篇
  1997年   882篇
  1996年   772篇
  1995年   660篇
  1994年   607篇
  1993年   520篇
  1992年   524篇
  1991年   406篇
  1990年   366篇
  1989年   349篇
  1988年   290篇
  1987年   278篇
  1986年   284篇
  1985年   253篇
  1984年   285篇
  1983年   238篇
  1982年   269篇
  1981年   219篇
  1980年   224篇
  1979年   155篇
  1978年   147篇
  1977年   126篇
  1976年   109篇
  1974年   111篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Journal of Medical Ultrasonics - Chronic liver disease is still a major problem because disease progression will ultimately lead to liver cirrhosis. Portal hypertension is the hallmark in advanced...  相似文献   
2.

The exercise pressor reflex is a feedback mechanism engaged upon stimulation of mechano- and metabosensitive skeletal muscle afferents. Activation of these afferents elicits a reflex increase in heart rate, blood pressure, and ventilation in an intensity-dependent manner. Consequently, the exercise pressor reflex has been postulated to be one of the principal mediators of the cardiorespiratory responses to exercise. In this updated review, we will discuss classical and recent advancements in our understating of the exercise pressor reflex function in both human and animal models. Particular attention will be paid to the afferent mechanisms and pathways involved during its activation, its effects on different target organs, its potential role in the abnormal cardiovascular response to exercise in diseased states, and the impact of age and biological sex on these responses. Finally, we will highlight some unanswered questions in the literature that may inspire future investigations in the field.

  相似文献   
3.
4.

Background

Hyperglycaemia is common in patients with acute brain injury admitted to an intensive care unit (ICU). Many studies have found associations between development of hyperglycaemia and increased mortality in hospitalised patients. However, the optimal target for blood glucose control is unknown. We want to conduct a systematic review with meta-analysis and trial sequential analysis to explore the beneficial and harmful effects of restrictive versus liberal glucose control on patient outcomes in adults with severe acute brain injury.

Methods

We will systematically search medical databases including CENTRAL, Embase, MEDLINE and trial registries. We will search the following websites for ongoing or unpublished trials: http://www.controlled-trials.com/ , http://www.clinicaltrials.gov/ , www.eudraCT.com , http://centerwatch.com/ , The Cochrane Library's CENTRAL, PubMed, EMBASE, Science Citation Index Expanded and CINAHL. Two authors will independently review and select trials and extract data. We will include randomised trials comparing levels of glucose control in our analyses and observational studies will be included to address potential harms. The primary outcomes are defined as all-cause mortality, functional outcome and health-related quality of life. Secondary outcomes include serious adverse events including hypoglycaemia, length of ICU stay and duration of mechanical ventilation, and explorative outcomes including intracranial pressure and infection. Trial Sequential Analysis will be used to investigate the risk of type I error due to repetitive testing and to further explore imprecision. Quality of trials will be evaluated using the Cochrane Risk of Bias tool, and quality of evidence will be assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach.

Discussion

The results of the systematic review will be disseminated through peer-reviewed publication. With the review, we hope to inform future randomised clinical trials and improve clinical practice.  相似文献   
5.
6.
7.
8.
The regulation of food intake is a complex mechanism, and the hypothalamus is the main central structure implicated. In particular, the arcuate nucleus appears to be the most critical area in the integration of multiple peripheral signals.Among these signals, those originating from the white adipose tissue and the gastrointestinal tract are known to be involved in the regulation of food intake.The present paper focuses on adiponectin, an adipokine secreted by white adipose tissue, which is reported to have a role in the control of feeding by acting centrally. The recent observation that adiponectin is also able to influence gastric motility raises the question of whether this action represents an additional peripheral mechanism that concurs with the central effects of the hormone on food intake. This possibility, which represents an emerging aspect correlating the central and peripheral effects of adiponectin in the hunger-satiety cycle, is discussed in the present paper.  相似文献   
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