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   4228118篇
  免费   361729篇
  国内免费   15109篇
耳鼻咽喉   60891篇
儿科学   132407篇
妇产科学   111945篇
基础医学   646283篇
口腔科学   119042篇
临床医学   383751篇
内科学   763142篇
皮肤病学   103410篇
神经病学   362152篇
特种医学   170885篇
外国民族医学   912篇
外科学   650275篇
综合类   125810篇
现状与发展   23篇
一般理论   2577篇
预防医学   355178篇
眼科学   100277篇
药学   301524篇
  19篇
中国医学   11006篇
肿瘤学   203447篇
  2021年   50170篇
  2020年   35643篇
  2019年   58822篇
  2018年   73412篇
  2017年   55713篇
  2016年   62126篇
  2015年   75392篇
  2014年   110278篇
  2013年   175632篇
  2012年   118012篇
  2011年   121174篇
  2010年   123177篇
  2009年   126332篇
  2008年   108240篇
  2007年   114755篇
  2006年   124277篇
  2005年   119430篇
  2004年   120347篇
  2003年   110675篇
  2002年   101212篇
  2001年   154320篇
  2000年   150067篇
  1999年   137803篇
  1998年   65616篇
  1997年   62040篇
  1996年   59830篇
  1995年   61016篇
  1994年   55210篇
  1993年   51211篇
  1992年   103642篇
  1991年   99276篇
  1990年   94326篇
  1989年   91916篇
  1988年   85409篇
  1987年   83937篇
  1986年   79622篇
  1985年   78045篇
  1984年   65843篇
  1983年   58630篇
  1982年   47738篇
  1981年   44482篇
  1980年   41762篇
  1979年   57662篇
  1978年   46811篇
  1977年   41260篇
  1976年   38356篇
  1975年   37609篇
  1974年   42268篇
  1973年   40424篇
  1972年   38012篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
71.
72.
73.
74.

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   
75.
76.
Journal of Neuro-Oncology - Craniopharyngiomas are locally-aggressive tumors arising along the hypothalamic-pituitary axis. Treatment is nuanced as a result of their proximity and adherence to...  相似文献   
77.
When hospitals first encountered coronavirus disease 2019 (COVID-19), there was a dearth of therapeutic options and nearly 1 in 3 patients died from the disease. By the summer of 2020, as deaths from the disease declined nationally, multiple single-center studies began to report declining mortality of patients with COVID-19. To evaluate the effect of COVID-19 on hospital-based mortality, we searched the Vizient Clinical Data Base for outcomes data from approximately 600 participating hospitals, including 130 academic medical centers, from January 2017 through December 2020. More than 32 million hospital admissions were included in the analysis. After an initial spike, mortality from COVID-19 declined in all regions of the country to under 10% by June 2020 and remained constant for the remainder of the year. Despite this, inpatient, all-cause mortality has increased since the beginning of the pandemic, even those without respiratory failure. Inpatient mortality has particularly increased in elderly patients and in those requiring intubation for respiratory failure. Since June 2020, COVID-19 kills one in every 10 patients admitted to the hospital with this diagnosis. The addition of this new disease has raised overall hospital mortality especially those who require intubation for respiratory failure.  相似文献   
78.
Network meta-analyses (NMAs) simultaneously estimate the effects of multiple possible treatment options for a given clinical presentation. For allergists to benefit optimally from NMAs, they must understand the process and be able to interpret the results. Through a worked example published in Pediatric Allergy and Immunology, we summarize how to identify credible NMAs and interpret them with a focus on recent innovations in the GRADE approach (Grading of Recommendations Assessment, Development, and Evaluation). NMAs build on traditional systematic reviews and meta-analyses that consider only direct paired comparisons by including indirect evidence, thus allowing the simultaneous assessment of the relative effect of all pairs of competing alternatives. Our framework informs clinicians of how to identify credible NMAs and address the certainty of the evidence. Trustworthy NMAs fill a critical gap in providing key inferences using direct and indirect evidence to inform clinical decision making when faced with more than two competing courses of treatment options. This document will help allergists to identify trustworthy NMAs to enhance patient care.  相似文献   
79.
80.
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