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   1471篇
  免费   116篇
  国内免费   1篇
耳鼻咽喉   15篇
儿科学   109篇
妇产科学   37篇
基础医学   158篇
口腔科学   25篇
临床医学   113篇
内科学   359篇
皮肤病学   12篇
神经病学   101篇
特种医学   37篇
外科学   151篇
综合类   21篇
一般理论   2篇
预防医学   117篇
眼科学   67篇
药学   112篇
中国医学   7篇
肿瘤学   145篇
  2024年   2篇
  2023年   15篇
  2022年   28篇
  2021年   65篇
  2020年   54篇
  2019年   66篇
  2018年   71篇
  2017年   45篇
  2016年   59篇
  2015年   49篇
  2014年   88篇
  2013年   84篇
  2012年   147篇
  2011年   150篇
  2010年   76篇
  2009年   59篇
  2008年   91篇
  2007年   101篇
  2006年   95篇
  2005年   67篇
  2004年   48篇
  2003年   38篇
  2002年   31篇
  2001年   10篇
  2000年   19篇
  1999年   1篇
  1998年   8篇
  1997年   2篇
  1996年   4篇
  1994年   2篇
  1993年   4篇
  1991年   3篇
  1990年   1篇
  1989年   1篇
  1987年   1篇
  1979年   1篇
  1974年   1篇
  1966年   1篇
排序方式: 共有1588条查询结果,搜索用时 15 毫秒
1.
A 13-year-old boy who had hemophilia A was reported with pain in the left thigh and hip on walking. He had no history of trauma. Severe hemophilia A is diagnosed with a Factor VIII level of <1 iu/dl. The presumptive diagnosis was that of a spontaneous bleed into the hip joint. Factor VIII mutational analysis revealed a C to G substitution at nucleotide 6683 which results in a cystine change at codon 2194. However, the symptoms persisted and an X-ray demonstrated the presence of an acute on chronic slip of the upper femoral epiphysis. The patient was transferred to the center treating his hemophilia where the hip was pinned in situ under cover with Factor VIII. This case demonstrates the need to be aware of a possible traumatic diagnosis of hip pain in a hemophiliac child with a longstanding history of spontaneous bleeding into joints.  相似文献   
2.
BACKGROUND: Formation of long-term memories is critically dependent on extracellular-regulated kinase (ERK) signaling. Activation of the ERK pathway by the sequential recruitment of mitogen-activated protein kinases is well understood. In contrast, the proteins that inactivate this pathway are not as well characterized. METHODS: Here we tested the hypothesis that the brain-specific striatal-enriched protein tyrosine phosphatase (STEP) plays a key role in neuroplasticity and fear memory formation by its ability to regulate ERK1/2 activation. RESULTS: STEP co-localizes with the ERKs within neurons of the lateral amygdala. A substrate-trapping STEP protein binds to the ERKs and prevents their nuclear translocation after glutamate stimulation in primary cell cultures. Administration of TAT-STEP into the lateral amygdala (LA) disrupts long-term potentiation (LTP) and selectively disrupts fear memory consolidation. Fear conditioning induces a biphasic activation of ERK1/2 in the LA with an initial activation within 5 minutes of training, a return to baseline levels by 15 minutes, and an increase again at 1 hour. In addition, fear conditioning results in the de novo translation of STEP. Inhibitors of ERK1/2 activation or of protein translation block the synthesis of STEP within the LA after fear conditioning. CONCLUSIONS: Together, these data imply a role for STEP in experience-dependent plasticity and suggest that STEP modulates the activation of ERK1/2 during amygdala-dependent memory formation. The regulation of emotional memory by modulating STEP activity may represent a target for the treatment of psychiatric disorders such as posttraumatic stress disorder (PTSD), panic, and anxiety disorders.  相似文献   
3.
BACKGROUND: Intracranial true mycotic aneurysms are uncommon and usually fatal. We report two patients with basilar mycotic aneurysms due to Aspergillus species following surgical interventions. Both patients had subarachnoid hemorrhage and diagnosis was made at autopsy only. The literature regarding etiology, clinical presentation, predisposing conditions and outcome of intracranial true mycotic aneurysms is reviewed from 1990-2005. A high index of clinical suspicion with prompt diagnosis and early treatment may improve patient outcome.  相似文献   
4.

Background  

The increasing use of complementary and alternative medicines in Australia has generated concern regarding the information on these products available to both healthcare providers and the public. The aim of this study was to examine the practice behaviours of naturopaths in relation to both the provision of and access to information on complementary and alternative medicines (CAM).  相似文献   
5.
6.
The frequency of proteinuria was assessed in a cohort of 1848 diabetic patients attending a diabetes centre in south India. A total of 127 (6.9%) patients had evidence of macroproteinuria and 49 (2.5%) patients had microproteinuria. Thus overall 9.4% of patients had diabetes related proteinuria. In addition, 70 patients (3.8%) had evidence of proteinuria with no evidence of retinopathy. The frequency of both microproteinuria and macroproteinuria increased linearly with duration of diabetes. Multiple logistic regression analysis showed that duration of diabetes, serum creatinine, and glycated haemoglobin were risk factors for macroproteinuria.  相似文献   
7.
The aim of this study was to determine the bioavailability of a novel oxazolidinone, DRF-6196, in mice and rats following intravenous (i.v) and oral dosing and to compare the pharmacokinetics with those obtained following linezolid dosing. Blood samples were drawn at predetermined intervals up to 24 h post-dose after either DRF-6196 or linezolid administration. The concentrations of DRF-6196 and linezolid in various plasma samples were determined by a HPLC method. Following oral administration maximum concentrations of DRF-6196 were achieved within 0.5 h irrespective of the species. While the doses increased in the ratio of 1 : 3 : 10, mean Cmax and AUC(0-infinity) values in mice for DRF-6196 increased in the ratio of 1 : 3.87 : 8.53 and 1 : 2.51 : 9.24, respectively. Both the Cmax and AUC(0-infinity) values increased almost proportional to the dose administered in mice. Following i.v administration, the concentration of DRF-6196 declined in a bi-exponential fashion with terminal elimination half-life of 1.5 h irrespective of the species. The systemic clearance and volume of distribution of DRF-6196 in mice were 1.14 L/h/kg and 0.66 L/kg, respectively after i.v administration, while the respective values in rats were 0.61 L/h/kg and 0.41L/kg, respectively. Elimination half-life ranged between 0.8-1.5 h. Absolute oral bioavailability of DRF-6196 was found to be 80-96% across the test dose range. Although plasma levels of DRF-6196 were lesser compared to linezolid in the initial hours, it may not have any consequences on the clinical effectiveness of the molecule.  相似文献   
8.
Purpose:To understand/assess ocular and functional vision impairment in children with multiple disabilities with a functional vision assessment battery in addition to standard ophthalmic examinations in an outreach setting.Methods:Seven schools for children with special needs, 243 children in total, were screened for ocular disorders and functional vision impairment through school camps.Results:Among them, 37% had refractive errors needing spectacle correction. With standard ocular testing methods, the visual impairment was around 32%, but when functional vision was assessed, the functional vision impairment amounted to 70% in these children. The presence of functional vision impairment was found to be independent of the associated disability. Assessment of visual capacities such as visual closure, saccade pursuits, optic ataxia, and developmental milestones early on can help in suspecting the presence of CVIConclusion:Children with multiple disabilities are more at risk of functional vision impairment, which significantly impairs their ability to function in daily life. A complete functional vision assessment becomes essential to plan early intervention for these children. The significant proportion of vision impairment and functional vision loss in our study indicates the need for coordinated structured programs to address vision-related problems in children with multiple disabilities.  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