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   2866篇
  免费   116篇
  国内免费   7篇
耳鼻咽喉   33篇
儿科学   173篇
妇产科学   52篇
基础医学   211篇
口腔科学   47篇
临床医学   168篇
内科学   599篇
皮肤病学   128篇
神经病学   303篇
特种医学   101篇
外科学   613篇
综合类   48篇
一般理论   1篇
预防医学   89篇
眼科学   75篇
药学   145篇
中国医学   8篇
肿瘤学   195篇
  2024年   1篇
  2023年   19篇
  2022年   16篇
  2021年   88篇
  2020年   76篇
  2019年   77篇
  2018年   100篇
  2017年   49篇
  2016年   59篇
  2015年   68篇
  2014年   132篇
  2013年   161篇
  2012年   262篇
  2011年   238篇
  2010年   133篇
  2009年   113篇
  2008年   214篇
  2007年   198篇
  2006年   186篇
  2005年   186篇
  2004年   141篇
  2003年   139篇
  2002年   117篇
  2001年   20篇
  2000年   16篇
  1999年   23篇
  1998年   26篇
  1997年   31篇
  1996年   21篇
  1995年   9篇
  1994年   12篇
  1993年   6篇
  1992年   1篇
  1991年   10篇
  1990年   5篇
  1989年   4篇
  1988年   1篇
  1987年   2篇
  1986年   5篇
  1985年   2篇
  1984年   6篇
  1983年   3篇
  1982年   3篇
  1981年   2篇
  1929年   1篇
  1919年   1篇
  1918年   2篇
  1917年   1篇
  1901年   2篇
  1892年   1篇
排序方式: 共有2989条查询结果,搜索用时 15 毫秒
71.
We report an infant with aortic valve atresia, interrupted aortic arch, ventricular septal defect, confluent pulmonary arteries, bilateral arterial ducts, absent common carotid arteries, and anomalous coronary arteries arising from main pulmonary artery. Hybrid procedure consisting of bilateral pulmonary artery banding and bilateral arterial duct stenting was performed at 4 weeks of age. Hybrid procedure can be an alternative palliative approach in an infant with this complex cardiac anatomy. © 2014 Wiley Periodicals, Inc.  相似文献   
72.
Gene amplifications in the 17q chromosomal region are observed frequently in breast cancers. An integrative bioinformatics analysis of this region nominated the MAP3K3 gene as a potential therapeutic target in breast cancer. This gene encodes mitogen‐activated protein kinase kinase kinase 3 (MAP3K3/MEKK3), which has not yet been reported to be associated with cancer‐causing genetic aberrations. We found that MAP3K3 was amplified in approximately 8–20% of breast cancers. Knockdown of MAP3K3 expression significantly inhibited cell proliferation and colony formation in MAP3K3‐amplified breast cancer cell lines MCF‐7 and MDA‐MB‐361 but not in MAP3K3 non‐amplified breast cancer cells. Knockdown of MAP3K3 expression in MAP3K3‐amplified breast cancer cells sensitized breast cancer cells to apoptotic induction by TNFα and TRAIL, as well as doxorubicin, VP‐16 and fluorouracil, three commonly used chemotherapeutic drugs for treating breast cancer. In addition, ectopic expression of MAP3K3, in collaboration with Ras, induced colony formation in both primary mouse embryonic fibroblasts and immortalized human breast epithelial cells (MCF‐10A). Combined, these results suggest that MAP3K3 contributes to breast carcinogenesis and may endow resistance of breast cancer cells to cytotoxic chemotherapy. Therefore, MAP3K3 may be a valuable therapeutic target in patients with MAP3K3‐amplified breast cancers, and blocking MAP3K3 kinase activity with a small molecule inhibitor may sensitize MAP3K3‐amplified breast cancer cells to chemotherapy. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
73.
74.
Infective endocarditis is extremely rare in children with structurally normal hearts. The most common etiological agents are staphylococcal and streptococcal species. Nutritionally variant streptococci also classified as Abiotrophia species are a group of fastidious organisms that account for only 5% to 6% of all cases of culture‐negative infective endocarditis. Only seven cases of Abiotrophia infective endocarditis have been previously reported in children with no underlying structural heart disease. We report two cases of Abiotrophia infective endocarditis in children without any predisposing factors. Both patients presented with nonspecific symptoms leading to delay in diagnosis. While bacteriological clearance was achieved in both cases, both had a complicated course including development of brain mycotic aneurysms, splenic infarction, renal failure, and irreversible damage to the mitral valve. Both patients required surgical removal of the native mitral valve and replacement. We also present review of seven cases with similar diagnosis published previously in literature and highlight important differences. Our cases highlight special challenges in management of Abiotrophia endocarditis in pediatric patients. As the organism may not be isolated in routine culture media, may present with atypical clinical symptoms and may have a complicated course even without antibiotic failure, a high index of suspicion should be maintained in children with subacute symptoms even with no underlying structural cardiac disease.  相似文献   
75.
The National Joint Registry (NJR) in England and Wales is currently the largest database of its kind in the world, with over one million records. Data entry has become compulsory, but even prior to this the registry has been 85% complete since inception. It offers web-based feedback to surgeons, hospitals and implant manufacturers, in addition to cooperating with other regulatory and professional bodies, and recently encouraging greater patient engagement. It produces annual reports covering what is occurring at a national level, with detailed analysis of patient demographics and large numbers of hip and knee arthroplasties, and more recently ankle replacements. It has been involved in the withdrawal of implants and assisting in the management of medical device alerts. It has many potential roles in improving patient outcomes, encouraging evidence-based practice and optimizing resource utilization.  相似文献   
76.
77.

Introduction

The purpose of this study was to compare the outcome of open treatment of mandibular fracture (symphysis or parasymphysis) using lag screw or mini plate clinically as well as radiologically in young (age range 12–45 years) and healthy individuals of poor socioeconomic status.

Method

This prospective study was conducted on 30 patients diagnosed as cases of displaced mandibular anterior fractures treated with open reduction and internal fixation. The patients were then randomly allocated to either of two groups––Group A: Two 2.5 mm stainless steel lag screws were placed in 15 patients. Group B: Two 2.5 mm stainless steel mini plates were placed in 15 patients for the fixation of fractures. Subsequent follow up was done on 2nd, 4th, 6th and 8th week postoperatively. During every follow up patient was assessed clinically for infection, malocclusion, loosening of plate/screw, sensory disturbance, plate fracture, malunion/non-union, devitalisation of associated dentoalveolar segment and masticatory efficiency. Radiographs were taken if necessary and patients were further assessed for any complaint. Pain was objectively measured using a visual analogue scale, bite force was measured using a bite force transducer at biweekly interval. The data collected was subjected to unpaired t test and paired t test for statistical analysis.

Results

During follow up period a significant improvement in bite force was present in both the groups, with more improvement seen in the lag screw group (p < 0.01). There was a significant pain reduction present in the lag screw group (p < 0.01) and also masticatory efficiency showed a steadier improvement in lag screw group while mini plate group patients showed a tendency to masticate only food items of medium hard consistency.

Conclusion

The sample size is small to conclude lag screws are better than mini plates but the result of our study provides a basis for further studies done to conclude that the application of LAG SCREW is an effective, inexpensive, quick treatment modality to accelerate healing of fresh, displaced mandibular anterior fracture.  相似文献   
78.
Purpose: The terms “electrical status epilepticus during sleep (ESES)” and “continuous spikes and waves during sleep (CSWS)” have been used interchangeably when referring to related but different concepts. In addition, the quantification of epileptiform activity has not been standardized, and different approaches to quantification have been used. The aim of this study was to evaluate the extent to which pediatric neurologists and epileptologists use a homogeneous terminology and conceptualization in CSWS and ESES and to characterize the current understanding of these conditions. Methods: A survey addressing the use of terminology in “ESES” and “CSWS” and the understanding of related concepts was distributed online to all members of the Child Neurology Society and the American Epilepsy Society mailing lists. Surveys were self‐administered and collected using an online survey website ( http://www.surveymonkey.com ). Key Findings: Two hundred nineteen surveys were completed, 137 from the Child Neurology Society mailing list and 82 from the American Epilepsy Society mailing list. ESES and CSWS were considered synonymous by 117 respondents, not synonymous by 61, 21 respondents did not know, and 20 did not respond. Most respondents (63.1%) considered CSWS as a devastating epileptic encephalopathy with severe sequelae even if treated correctly, but 25.1% of respondents indicated that it does not leave sequelae if epilepsy was treated early and another 11.8% noted that cognitive difficulties resolved with age. Cognitive and/or language regression were considered mandatory for the diagnosis of CSWS by only 27% of the respondents. The diagnosis of CSWS was based on electroencephalography (EEG) assessment alone by 31% of respondents. Respondents used different methods for calculation of the epileptiform activity, different EEG samples for calculation, and considered differently the lateralized epileptiform activity. The cut‐off values for percentage of the sleep record occupied by spike‐waves were variable depending on the respondent. There was no agreement on whether these cutoff values were mandatory for the diagnosis of ESES and CSWS. Significance: Our data show that the professionals caring for children with ESES and CSWS in North America use the terms, concepts, and defining features heterogeneously. The lack of a common language may complicate communication among clinicians and jeopardize research in this field. We anticipate that our data will fuel the development of much needed common terminology and conceptualization of ESES and CSWS.  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