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   1008篇
  免费   43篇
  国内免费   26篇
耳鼻咽喉   1篇
儿科学   18篇
妇产科学   2篇
基础医学   86篇
口腔科学   16篇
临床医学   64篇
内科学   177篇
皮肤病学   4篇
神经病学   256篇
特种医学   209篇
外科学   83篇
综合类   17篇
预防医学   78篇
眼科学   11篇
药学   28篇
肿瘤学   27篇
  2023年   7篇
  2022年   14篇
  2021年   16篇
  2020年   9篇
  2019年   14篇
  2018年   12篇
  2017年   12篇
  2016年   15篇
  2015年   26篇
  2014年   26篇
  2013年   38篇
  2012年   52篇
  2011年   47篇
  2010年   29篇
  2009年   35篇
  2008年   36篇
  2007年   59篇
  2006年   55篇
  2005年   29篇
  2004年   32篇
  2003年   30篇
  2002年   28篇
  2001年   27篇
  2000年   21篇
  1999年   15篇
  1998年   30篇
  1997年   10篇
  1996年   25篇
  1995年   21篇
  1994年   25篇
  1993年   11篇
  1992年   25篇
  1991年   30篇
  1990年   24篇
  1989年   25篇
  1988年   29篇
  1987年   24篇
  1986年   17篇
  1985年   23篇
  1984年   6篇
  1983年   6篇
  1982年   4篇
  1981年   8篇
  1980年   6篇
  1978年   4篇
  1977年   5篇
  1976年   4篇
  1975年   3篇
  1974年   3篇
  1969年   3篇
排序方式: 共有1077条查询结果,搜索用时 15 毫秒
31.
Food security and nutrition play an important role in HIV and TB care and treatment, including for improving treatment outcomes, adherence and uptake of HIV and TB care. This AIDS and behaviour supplement on “Adherence to HIV and TB care and treatment, the role of food security and nutrition” provides an overview of the current evidence and knowledge about the barriers to uptake and retention in HIV and TB treatment and care and on whether and how food and nutrition assistance can help overcome these barriers. It contains nine papers on three topic areas discussing: (a) adherence and food and nutrition security in context of HIV and TB, their definitions, measurement tools and the current situation; (b) food and nutrition insecurity as barriers to uptake and retention; and (c) food and nutrition assistance to increase uptake and retention in care and treatment. Future interventions in the areas of food security, nutrition and social protection for increasing access and adherence should be from an HIV sensitive lens, linking the continuum of care with health systems, food systems and the community, complementing existing platforms through partnerships and integrated services.  相似文献   
32.
Socioeconomic costs of HIV and TB and the difficulty of maintaining optimal treatment are well documented. Social protection measures such as food assistance may be required to offset some of the treatment related costs as well as to ensure food security and maintain good health of the affected individual and household. Programmes have started placing greater emphasis on treatment adherence and are looking for proven interventions that can optimize it. This paper looks at the effect of food assistance for enabling treatment adherence and reviews studies that used food assistance to promote adherence. Eight of ten studies found that provision of food can improve adherence and/or treatment completion for HIV care and treatment, ART and TB-DOTS. This indicates that food provision is not only a biological, but also a behavioural intervention, and underscores that unresolved food insecurity can be an impediment to treatment adherence and consequently to good treatment outcomes.  相似文献   
33.
34.
Postural instability and gait disorders (PIGD) in Parkinson's disease (PD) seem to be associated with executive dysfunction. We investigated which specific executive functions are associated with functional mobility in mildly affected PD patients. Functional mobility (Timed Up&Go Test, TUG), PIGD score, (spatial) working memory, set shifting, response inhibition and response generation were assessed in a large cohort of 232 non-demented PD patients. Both performance on the TUG and PIGD score were weakly associated with working memory and response generation (semantic and phonemic fluency). TUG also correlated with semantic fluency when corrected for disease severity and age. These results indicate that response generation and working memory are associated with (and possibly also causally related to) gait and balance deficits. In order to fully interpret gait and postural stability of PD patients in everyday situations, the role of impairments in working memory and response generation should be taken into account.  相似文献   
35.
BackgroundAlthough physical activity is beneficial for Parkinson's disease (PD) patients, many do not meet the recommended levels. The range of physical activity among sedentary PD patients is unknown, as are factors that determine this variability. Hence, we aimed to (1) assess daily physical activity in self-identified sedentary PD patients; (2) compare this with criteria of a daily physical activity guideline; and (3) identify determinants of daily physical activity.MethodsDaily physical activity of 586 self-identified sedentary PD patients was measured with a tri-axial accelerometer for seven consecutive days. Physical fitness and demographic, disease-specific, and psychological characteristics were assessed. Daily physical activity was compared with the 30-min activity guideline. A linear mixed-effects model was estimated to identify determinants of daily physical activity.ResultsAccelerometer data of 467 patients who fulfilled all criteria revealed that >98% of their day was spent on sedentary to light-intensity activities. Eighty-two percent of the participants were ‘physically inactive’ (0 days/week of 30-min activity); 17% were ‘semi-active’ (1–4 days/week of 30-min activity). Age, gender, physical fitness, and scores on the Unified Parkinson's Disease Rating Scale explained 69% of the variability in daily physical activity.ConclusionsPerformance-based measurements confirmed that most self-identified sedentary PD patients are ‘physically inactive’. However, the variance in daily physical activity across subjects was considerable. Higher age, being female, and lower physical capacity were the most important determinants of reduced daily physical activity. Future therapeutic interventions should aim to improve daily physical activity in these high-risk patients, focusing specifically on modifiable risk factors.  相似文献   
36.

Introduction

This multicentre randomised controlled trial was designed to explore whether 6 weeks above-elbow cast (AEC) or 3 weeks AEC followed by 3 weeks below-elbow cast (BEC) cause similar limitation of pronation and supination in non-reduced diaphyseal both-bone forearm fractures in children.

Materials and methods

Children were randomly allocated to 6 weeks AEC or to 3 weeks AEC followed by 3 weeks BEC. The primary outcome was limitation of pronation and supination after 6 months. The secondary outcomes were re-displacement of the fracture, complication rate, limitation of flexion and extension of wrist and elbow, cast comfort, cosmetics, complaints in daily life and assessment of radiographs.

Results

A group of 23 children was treated with 6 weeks AEC and 24 children with 3 weeks AEC and 3 weeks BEC. The follow-up rate was 98 % with a mean follow-up of 7.0 months. The mean limitation of pronation and supination was 23.3 ± 22.0 for children treated with AEC and 18.0 ± 16.9 for children treated with AEC and BEC. The other study outcomes were similar in both groups.

Conclusions

Early conversion to BEC is safe in the treatment of non-reduced diaphyseal both-bone forearm fractures in children.

Level of evidence

Multicentre randomised controlled trial, Level II.  相似文献   
37.
Imaging and neuropathology studies have demonstrated significant abnormalities not only in subcortical, but also in cortical regions of patients with multiple system atrophy (MSA). This raises the possibility that cognitive dysfunction may contribute to the clinical spectrum of this disorder to a greater extent than it is currently not widely appreciated. In this cross-sectional multicenter study from the European multiple system atrophy study group (http://www.emsa-sg.org), we applied an extensive neuropsychological test battery in a series of 61 clinically diagnosed probable MSA patients. The results demonstrated that general cognitive decline as assessed by MMSE was uncommon (2 out of 61 patients <24). In contrast, frontal lobe-related functions (as measured by FAB) were impaired in 41 % of patients, with abstract reasoning and sustained attention less compromised. This pattern was similar to our control group of 20 patients with Parkinson’s disease (matched for disease duration and age at onset). There was no difference in cognitive performance between MSA patients with the parkinsonian versus the cerebellar variant. Behaviourally, MSA patients had greater depression than PD and in the case of MSA of the cerebellar variant significantly lower anxiety. Our data show that cognitive abnormalities are relatively frequent in multiple system atrophy and this involves primarily frontal-executive functions. Their contribution to clinical disability and disease progression needs to be addressed in larger prospective studies.  相似文献   
38.
39.
Travel distance, growing disability, and uneven distribution of doctors limit access to care for most Parkinson's disease (PD) patients worldwide. Telemedicine, the use of telecommunications technology to deliver care at a distance, can help overcome these barriers. In this report, we describe the past, present, and likely future applications of telemedicine to PD. Historically, telemedicine has relied on expensive equipment to connect single patients to a specialist in pilot programs in wealthy nations. As the cost of video conferencing has plummeted, these efforts have expanded in scale and scope, now reaching larger parts of the world and extending the focus from care to training of remote providers. Policy, especially limited reimbursement, currently hinders the growth and adoption of these new care models. As these policies change and technology advances and spreads, the following will likely develop: integrated care networks that connect patients to a wide range of providers; education programs that support patients and health care providers; and new research applications that include remote monitoring and remote visits. Together, these developments will enable more individuals with PD to connect to care, increase access to expertise for patients and providers, and allow more‐extensive, less‐expensive participation in research. © 2014 International Parkinson and Movement Disorder Society  相似文献   
40.
Hypertrophy is an adaptive response of the heart to myocardial injury or hemodynamic overload that may progress and contribute to cardiac decompensation and eventually to heart failure. The signaling pathways controlling this response in the cardiac myocyte are poorly understood. A data mining effort of a human failed heart cDNA library was undertaken in an effort to identify novel signaling molecules involved in cardiac hypertrophy. This effort identified a novel kinase (MLK7) homologous to the mixed lineage kinase family of proteins. The mixed lineage kinases are mitogen-activated protein kinase kinase kinases (MAPKKKs) which activate stress activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK) and p38 kinase pathways. They contain a catalytic domain with homology to both serine/threonine and tyrosine-specific kinases and a dual leucine zipper. MLK7 is identical to leucine zipper and sterile-alpha motif protein kinase (ZAK) through the leucine zipper domain but has a completely divergent COOH-terminus and shares approximately 40% homology with the other MLKs overall. Expression of MLK7 mRNA is most abundant in skeletal muscle and heart, with expression restricted to the cardiac myocyte. The recombinant histidine tagged MLK7 expressed and purified from insect cells exhibited serine/threonine kinase activity in vitro with myelin basic protein as substrate. When expressed in cardiac myocytes, MLK7 activated SAPK/JNK1, and ERK and p38 to a lesser extent. Additionally, MLK7 altered fetal gene expression and increased protein synthesis in cardiac myocytes. These data suggest that MLK7 is a new member of the mixed lineage kinase family that modulates cardiac SAPK/JNK pathway and may play a role in cardiac hypertrophy and progression to heart failure.  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