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   3501篇
  免费   175篇
  国内免费   13篇
耳鼻咽喉   18篇
儿科学   71篇
妇产科学   62篇
基础医学   544篇
口腔科学   111篇
临床医学   244篇
内科学   843篇
皮肤病学   103篇
神经病学   242篇
特种医学   90篇
外科学   595篇
综合类   16篇
预防医学   246篇
眼科学   33篇
药学   219篇
中国医学   3篇
肿瘤学   249篇
  2023年   23篇
  2022年   53篇
  2021年   103篇
  2020年   54篇
  2019年   97篇
  2018年   106篇
  2017年   91篇
  2016年   83篇
  2015年   86篇
  2014年   108篇
  2013年   144篇
  2012年   252篇
  2011年   253篇
  2010年   171篇
  2009年   146篇
  2008年   219篇
  2007年   225篇
  2006年   198篇
  2005年   197篇
  2004年   198篇
  2003年   180篇
  2002年   168篇
  2001年   52篇
  2000年   66篇
  1999年   45篇
  1998年   33篇
  1997年   28篇
  1996年   22篇
  1995年   11篇
  1994年   18篇
  1993年   20篇
  1992年   24篇
  1991年   21篇
  1990年   16篇
  1989年   12篇
  1988年   10篇
  1987年   8篇
  1986年   8篇
  1985年   14篇
  1984年   12篇
  1983年   10篇
  1982年   8篇
  1981年   5篇
  1979年   8篇
  1975年   6篇
  1972年   5篇
  1971年   7篇
  1970年   6篇
  1968年   7篇
  1939年   4篇
排序方式: 共有3689条查询结果,搜索用时 12 毫秒
81.
82.
Qualitative research of brigades and the family experience of congenital heart disease is of current interest and has been previously neglected. This study aimed to explore the social factors conditioning outcomes of paediatric cardiology care in the setting of Colombian medical brigades and to identify feasible strategies to improve the experience of the beneficiary populations. Participants were selected using purposeful sampling. Semi-structured interviews were conducted with members of logistic and health care teams, caregivers and custodians of beneficiary children of the Programme. The data collected provided an understanding of the health culture, social background, household and intrafamily dynamics. The outcomes of the Programme are influenced by sociocultural dynamics such as communication gaps and the socioeconomic status of the beneficiary populations. Findings may be specific to brigades, but also cross-relevant to any family experience of a new diagnosis of Congenital Heart Disease (CHD) communicating with healthcare professionals. It is important to foresee the role and further development of the Programme. Recommendations are provided suggesting innovative work by means of telemedicine and other sociocultural measures to reduce healthcare inequity and strengthen comprehensive healthcare programmes.  相似文献   
83.
84.
85.
Systemic delivery of (1R-1-benzo thiophen-5-yl-2[2-diethylamino)-ethoxy] ethanol hydrochloride (T-588) prevented long-term depression (LTD) of the parallel fiber (PF)-Purkinje cell (PC) synapse induced by conjunctive climbing fiber and PF stimulation in vivo. However, similar concentrations of T-588 in the brains of behaving mice and rats affected neither motor learning in the rotorod test nor the learning of motor timing during classical conditioning of the eyeblink reflex. Rats given doses of T-588 that prevented PF-PC LTD were as proficient as controls in learning to adapt the timing of their conditioned eyeblink response to a 150- or 350-ms change in the timing of the paradigm. The experiment indicates that PF-PC LTD under control of the climbing fibers is not required for general motor adaptation or the learning of response timing in two common models of motor learning for which the cerebellum has been implicated. Alternative mechanisms for motor timing and possible functions for LTD in protection from excitotoxicity are discussed.  相似文献   
86.
Parkinson's disease (PD) consists of a neurodegenerative pathology that has received a considerable amount of attention because of its clinical manifestations. The most common treatment consists of administering the drugs levodopa and biperiden, which reduce the effectiveness of the disease and the progress of its symptoms. However, phytotherapy treatment of PD has shown great potential in retarding the loss of dopaminergic neurons and minimizing the behavioral abnormalities. The aim of this study is to systematically review the use of supplemental herbal plants with cellular protective effect and behavioral activity in in vivo and in vitro experimental models. A total of 20 studies were summarized, where the effectiveness of herbal extracts and their isolated bioactive compounds was observed in animal models for PD. The main neurochemical mechanisms found in these studies are schematically represented. The herbal extracts and their biocompounds have antioxidant, anti‐apoptotic, and antiinflammatory properties, which contribute to avoiding neuronal loss. Reports show that besides acting on the biosynthesis of dopamine and its metabolites, these compounds prevent D2 receptors' hypersensitivity. It is suggested that further studies need be conducted to better understand the mechanisms of action of the bioactive compounds distributed in these plants. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
87.
To describe clinical, pulmonary function, and chest tomography profiles in a 5-year follow-up of infants with adenovirus pneumonia and determine the factors that potentially contributed to the development of bronchiolitis obliterans (BO). We prospectively assessed 45 hospitalized infants with adenovirus pneumonia with additional follow-up for 5 years. At the end of the study, pulmonary function by impulse oscillometry technique (IOS) and chest tomography were performed in the 38 surviving patients (mean 5.7 years of age). We divided the population between those who developed chest tomography evidence of BO and those who did not. Most of the children developed adenovirus infection before 2 years of age. During the 5 years of follow-up, almost half (47.4%) developed BO. Children who developed BO had significantly more respiratory compromise (intensive care admission, need for mechanical ventilation and for oxygen therapy, and systemic corticosteroid and beta agonist use) during their adenovirus pneumonia episode than those who did not develop BO. Only 33.3% of children with BO had normal impedance compared with 85% in the no BO group. Children who developed BO had significantly higher levels of Zrs, R5, X5 and predicted Zrs, R5, and X5 and frequency. However, there were no differences in the beta 2 agonist response between the children with and without BO (94% vs. 80%, respectively). This study represents the spectra of adenovirus pneumonia ranging from relatively mild to severe and fatal cases. Children with severe pulmonary compromise are usually more prone to develop BO.  相似文献   
88.
89.
Myoepithelial carcinoma is a rare locally aggressive malignant neoplasm of the salivary glands. The tumor is composed almost exclusively of tumor cells with myoepithelial differentiation and characterized by infiltrative growth and potential for distant metastasis. Tumor cells often display morphologic heterogeneity with a wide range of cytomorphologic features, such as epithelioid, plasmacytoid, spindle, and clear cell types, making its recognition challenging. Only limited reports on its metastatic behavior are available in the literature. We describe a case of metastatic myoepithelial carcinoma of the kidney from the parotid gland diagnosed by computed tomography guided fine‐needle aspiration biopsy. Immunochemical studies are important to confirm myoepithelial differentiation of the tumor cells. Knowledge of the clinical history, radiographic characterization, andmorphological correlation with the primary tumor are emphasized. Diagn. Cytopathol. 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
90.
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