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   3650篇
  免费   240篇
  国内免费   6篇
耳鼻咽喉   76篇
儿科学   144篇
妇产科学   101篇
基础医学   511篇
口腔科学   35篇
临床医学   359篇
内科学   672篇
皮肤病学   36篇
神经病学   612篇
特种医学   117篇
外国民族医学   5篇
外科学   384篇
综合类   17篇
预防医学   290篇
眼科学   42篇
药学   247篇
肿瘤学   248篇
  2023年   20篇
  2022年   36篇
  2021年   99篇
  2020年   57篇
  2019年   70篇
  2018年   91篇
  2017年   80篇
  2016年   62篇
  2015年   70篇
  2014年   94篇
  2013年   149篇
  2012年   210篇
  2011年   216篇
  2010年   126篇
  2009年   109篇
  2008年   155篇
  2007年   207篇
  2006年   141篇
  2005年   161篇
  2004年   166篇
  2003年   123篇
  2002年   135篇
  2001年   85篇
  2000年   97篇
  1999年   101篇
  1998年   32篇
  1997年   31篇
  1996年   30篇
  1995年   25篇
  1994年   20篇
  1993年   20篇
  1992年   56篇
  1991年   72篇
  1990年   64篇
  1989年   60篇
  1988年   46篇
  1987年   54篇
  1986年   59篇
  1985年   60篇
  1984年   53篇
  1983年   32篇
  1981年   21篇
  1979年   39篇
  1978年   20篇
  1976年   21篇
  1974年   26篇
  1973年   18篇
  1972年   26篇
  1970年   24篇
  1969年   16篇
排序方式: 共有3896条查询结果,搜索用时 343 毫秒
71.
72.

Background  

Granulocytes generally exert protective roles in the central nervous system (CNS), but recent studies suggest that they can be detrimental in experimental autoimmune encephalomyelitis (EAE), the most common model of multiple sclerosis. While the cytokines and adhesion molecules involved in granulocyte adhesion to the brain vasculature have started to be elucidated, the required chemokines remain undetermined.  相似文献   
73.
Endurance and ultra-endurance events have become increasingly popular. The aim of our study was to explore the use of medication among endurance runners participating in the 2014 Infernal Trail des Vosges. Among the 389 runners engaged, 297 (76.3%) completed a specific questionnaire dealing with substance use/misuse. Our results show a 27% (before the race) and 18% (during the race) prevalence of substance use. The two major classes of substances used were non-steroidal anti-inflammatory drugs (NSAIDs; 9.8%) and painkillers (6.7%), principally because of osteo-articular pain (29.6%) or to prevent pain (28.2%). A positive correlation was found between substance consumption before (past month) and during the race (overall medication: p < 0.0001; NSAIDs: p = 0.008). Our results could be explained by the specific characteristics of ultrarunners predominantly motivated by personal achievement and general health (recreational approach). However, education interventions should further be delivered regarding the risks of substance use in ultra-endurance events.  相似文献   
74.
There are often discrepancies when using different methods to measure anti-Toxoplasma gondii IgG levels in patient samples. The diagnostic performance of a chemiluminescent immunoassay (CLIA) and an enzyme-linked fluorescent assay (ELFA) used as confirmatory tests for samples identified as positive or equivocal by an electrochemiluminescent immunoassay (ECLIA) were examined. Cut-off values were those stated by the manufacturer, and Western blot was used to confirm the results of all methods. All samples identified as positive by ECLIA (n = 93) were confirmed as positive by Western blot, as were 14 of the 28 samples identified as equivocal. When these 121 samples were retested, the sensitivities of CLIA and ELFA were 64.4% and 73.8%, respectively. Both methods exhibited a specificity of 100%. This study confirms that the results obtained from the different immunoassays are not comparable, and neither CLIA nor ELFA should be used to confirm ECLIA results, which should instead be confirmed by methods such as Western blot or Sabin-Feldman dye test.  相似文献   
75.
76.
This paper describes the development of a polyimide-based MEMS strain-sensing device. Finite element analysis was used to investigate an artificial knee implant and assist on device design and to optimize sensing characteristics. The sensing element of the device was fabricated using polyimide micromachining with embedded thin-metallic wires and placed into a knee prosthesis. The device was evaluated experimentally in a mechanical knee simulator using static and dynamic axial load conditions similar to those encountered in vivo. Results indicates the sensor is capable of measuring the strain associated to the total axial forces in the range of approximately 4 times body weight with a good sensitivity and accuracy for events happening within 1 s time window.  相似文献   
77.
G. Dumas  E. Canet 《Réanimation》2016,25(3):123-136
Survival of cancer patients has dramatically increased with the development of new treatments such as targeted therapies. Nevertheless, physicians now face new challenges as identifying and addressing treatment toxicities. While infection remains the leading cause of intensive care unit (ICU) admissions in these patients, various cardiovascular toxicities may occur during multiple lines of chemotherapy and targeted therapies, with progressively higher cumulative doses. Anthracyclines cardiotoxicity was identified in 1950 and has been extensively reported. More recently, multiple cardiovascular side effects of targeted therapies (monoclonal antibodies and tyrosine kinase inhibitors) have been described, including severe hypertension, cardiac failure, arrhythmia, myocardial ischemia, and pericardial effusion. In addition, the risk of both venous and arterial thromboembolic events is increased with the use of chemotherapy and targeted therapies, which can lead to ICU admission in the severe forms or because of bleeding events related to anticoagulation therapy. Microvascular endothelial cell injuries induced by cancer therapies or immunosuppressive agents may be responsible for thrombotic microangiopathy or posterior reversible encephalopathy syndrome. Finally, acute hypersensitivity reactions to chemotherapy or monoclonal antibodies can cause changes in blood pressure or anaphylactoid shock in the most severe cases. Critically ill cancer patients who experienced chemotherapy-related cardiovascular events require the same therapeutic approach to the cardiopathic patients. Maximal intensive care support is justified as most of these toxicities are potentially reversible.  相似文献   
78.
The vestibulo-ocular reflex maintains gaze stabilization during angular or linear head accelerations, allowing adequate dynamic visual acuity. In case of bilateral vestibular hypofunction, patients use saccades to compensate for the reduced vestibulo-ocular reflex function, with covert saccades occurring even during the head displacement. In this study, we questioned whether covert saccades help maintain dynamic visual acuity, and evaluated which characteristic of these saccades are the most relevant to improve visual function. We prospectively included 18 patients with chronic bilateral vestibular hypofunction. Subjects underwent evaluation of dynamic visual acuity in the horizontal plane as well as video recording of their head and eye positions during horizontal head impulse tests in both directions (36 ears tested). Frequency, latency, consistency of covert saccade initiation, and gain of covert saccades as well as residual vestibulo-ocular reflex gain were calculated. We found no correlation between residual vestibulo-ocular reflex gain and dynamic visual acuity. Dynamic visual acuity performance was however positively correlated with the frequency and gain of covert saccades and negatively correlated with covert saccade latency. There was no correlation between consistency of covert saccade initiation and dynamic visual acuity. Even though gaze stabilization in space during covert saccades might be of very short duration, these refixation saccades seem to improve vision in patients with bilateral vestibular hypofunction during angular head impulses. These findings emphasize the need for specific rehabilitation technics that favor the triggering of covert saccades. The physiological origin of covert saccades is discussed.  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