首页 | 官方网站   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   22912篇
  免费   1244篇
  国内免费   260篇
医药卫生   24416篇
  2023年   172篇
  2022年   173篇
  2021年   651篇
  2020年   451篇
  2019年   532篇
  2018年   706篇
  2017年   570篇
  2016年   651篇
  2015年   727篇
  2014年   948篇
  2013年   1149篇
  2012年   1817篇
  2011年   1827篇
  2010年   1034篇
  2009年   1009篇
  2008年   1650篇
  2007年   1624篇
  2006年   1475篇
  2005年   1401篇
  2004年   1370篇
  2003年   1236篇
  2002年   1081篇
  2001年   161篇
  2000年   136篇
  1999年   165篇
  1998年   152篇
  1997年   123篇
  1996年   132篇
  1995年   131篇
  1994年   85篇
  1993年   95篇
  1992年   102篇
  1991年   79篇
  1990年   66篇
  1989年   80篇
  1988年   60篇
  1987年   67篇
  1986年   57篇
  1985年   44篇
  1984年   57篇
  1983年   53篇
  1982年   36篇
  1981年   42篇
  1980年   44篇
  1979年   22篇
  1978年   15篇
  1977年   21篇
  1976年   16篇
  1974年   20篇
  1971年   9篇
排序方式: 共有10000条查询结果,搜索用时 24 毫秒
41.
Journal of Neurology - In amyotrophic lateral sclerosis (ALS), the involvement of lower motor neuron is well defined by electromyography, whereas a reliable marker of upper motor neuron (UMN)...  相似文献   
42.
The nondystrophic myotonias are rare muscle hyperexcitability disorders caused by gain-of-function mutations in the SCN4A gene or loss-of-function mutations in the CLCN1 gene. Clinically, they are characterized by myotonia, defined as delayed muscle relaxation after voluntary contraction, which leads to symptoms of muscle stiffness, pain, fatigue, and weakness. Diagnosis is based on history and examination findings, the presence of electrical myotonia on electromyography, and genetic confirmation. In the absence of genetic confirmation, the diagnosis is supported by detailed electrophysiological testing, exclusion of other related disorders, and analysis of a variant of uncertain significance if present. Symptomatic treatment with a sodium channel blocker, such as mexiletine, is usually the first step in management, as well as educating patients about potential anesthetic complications.  相似文献   
43.
44.
45.
Introduction: The management of non-small cell lung cancer (NSCLC) has been substantially improved in the last few years; it has been revolutionized by a patient-tailored approach, especially in the oncogene addicted disease, and by novel combinations containing immune checkpoint inhibitors. However, chemotherapy still represents a mainstay that persists over the decades with limited novelties. Tubulin inhibitors belong to different sub-classes of drugs that share the capability to interfere with mitosis by a direct action on the microtubule system. Among them, taxanes and vinca alkaloids still have a prominent role in clinical practice.

Areas covered: This review summarizes the mechanisms of action, current role and future directions of microtubule targeting agents; we focus on investigational agents in phase I and II clinical trials.

Expert opinion: Chemotherapy maintains a pivotal role in the treatment of NSCLC. New generation agents that have the potential to overcome the mechanisms of resistance to the available drugs may provide new therapeutic opportunities. Predictive biomarkers derived from combination strategies and phase III studies are necessary going forward.  相似文献   

46.
47.
48.

Background

Scientific guidelines consider atrial fibrillation (AF) complicating degenerative mitral regurgitation (DMR) a debated indication for surgery.

Objectives

This study analyzed the prognostic/therapeutic implications of AF at DMR diagnosis and long-term.

Methods

Patients were enrolled in the MIDA (Mitral Regurgitation International Database) registry, which reported the consecutive, multicenter, international experience with DMR due to flail leaflets echocardiographically diagnosed.

Results

Among 2,425 patients (age 67 ± 13 years; 71% male, 67% asymptomatic, ejection fraction 64 ± 10%), 1,646 presented at diagnosis with sinus rhythm (SR), 317 with paroxysmal AD, and 462 with persistent AF. Underlying clinical/instrumental characteristics progressively worsened from SR to paroxysmal to persistent AF. During follow-up, paroxysmal and persistent AF were associated with excess mortality (10-year survival in SR and in paroxysmal and persistent AF was 74 ± 1%, 59 ± 3%, and 46 ± 2%, respectively; p < 0.0001), that persisted 20 years post-diagnosis and independently of all baseline characteristics (p values <0.0001). Surgery (n = 1,889, repair 88%) was associated with better survival versus medical management, regardless of all baseline characteristics and rhythm (adjusted hazard ratio: 0.26; 95% confidence interval: 0.23 to 0.30; p < 0.0001) but post-surgical outcome remained affected by AF (10-year post-surgical survival in SR and in paroxysmal and persistent AF was 82 ± 1%, 70 ± 4%, and 57 ± 3%, respectively; p < 0.0001).

Conclusions

AF is a frequent occurrence at DMR diagnosis. Although AF is associated with older age and more severe presentation of DMR, it is independently associated with excess mortality long-term after diagnosis. Surgery is followed by improved survival in each cardiac rhythm subset, but persistence of excess risk is observed for each type of AF. Our study indicates that detection of AF, even paroxysmal, should trigger prompt consideration for surgery.  相似文献   
49.
50.
Introduction: Treatment of HIV infection has consistently evolved in the last three decades. A steady improvement in efficacy tolerability, safety, and practical aspects of treatment intake has made HIV infection much easier to manage over the long term, and in optimal treatment conditions the life expectancy of persons living with HIV infection now approaches the values of the general population. The last category of antiretrovirals to be fully developed for clinical use is the one of strand-transfer integrase inhibitors (INSTIs).

Areas covered: In this review, the evolution of the knowledge on INSTIs use in the clinical setting is reviewed, analyzed, and interpreted. Emphasis is placed on the properties possibly accounting for several superiority results achieved by INSTIs in non-inferiority designed comparative clinical trials, which led to their inclusion as first line options in all versions of HIV therapeutic guidelines.

Expert commentary: Some unprecedented clinical-pharmacological properties of INSTIs, such as their rapid and sustained action against HIV replication, the optimal tolerability and safety profile and a clinically proven robust genetic barrier are the main factors justifying the successful clinical use of INSTIs. Based on these unique features, novel INSTIs-based treatment modalities are being developed, including the reduction of antiretroviral regimens to two drugs only.  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-23

京公网安备 11010802026262号