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   36052篇
  免费   2287篇
  国内免费   96篇
耳鼻咽喉   368篇
儿科学   880篇
妇产科学   750篇
基础医学   4768篇
口腔科学   780篇
临床医学   3338篇
内科学   7479篇
皮肤病学   553篇
神经病学   3886篇
特种医学   1444篇
外国民族医学   55篇
外科学   4762篇
综合类   451篇
一般理论   16篇
预防医学   3146篇
眼科学   940篇
药学   2465篇
中国医学   34篇
肿瘤学   2320篇
  2022年   195篇
  2021年   557篇
  2020年   314篇
  2019年   547篇
  2018年   622篇
  2017年   514篇
  2016年   541篇
  2015年   708篇
  2014年   993篇
  2013年   1454篇
  2012年   2199篇
  2011年   2310篇
  2010年   1267篇
  2009年   1204篇
  2008年   2105篇
  2007年   2325篇
  2006年   2209篇
  2005年   2204篇
  2004年   2095篇
  2003年   1953篇
  2002年   1857篇
  2001年   490篇
  2000年   402篇
  1999年   430篇
  1998年   412篇
  1997年   376篇
  1996年   316篇
  1995年   312篇
  1994年   257篇
  1993年   256篇
  1992年   266篇
  1991年   229篇
  1990年   217篇
  1989年   252篇
  1988年   224篇
  1987年   214篇
  1986年   191篇
  1985年   191篇
  1984年   251篇
  1983年   210篇
  1982年   251篇
  1981年   227篇
  1980年   207篇
  1979年   173篇
  1978年   166篇
  1977年   117篇
  1976年   151篇
  1975年   132篇
  1974年   157篇
  1973年   118篇
排序方式: 共有10000条查询结果,搜索用时 375 毫秒
991.
992.
Growth hormone (GH) is widely prescribed for children with short stature across a range of growth disorders. Recombinant human (rh) insulin‐like growth factor‐1 (rhIGF‐1) therapy is approved for severe primary IGF‐I deficiency – a state of severe GH resistance. Evidence is increasing for an unacceptably high rate of poor or unsatisfactory response to growth‐promoting therapy (i.e. not leading to significant catch up growth) in terms of change in height standard deviation score (SDS) and height velocity (HV) in many approved indications. Consequently, there is a need to define poor response and to prevent or correct it by optimizing treatment regimens within accepted guidelines. Recognition of a poor response is an indication for action by the treating physician, either to modify the therapy or to review the primary diagnosis leading either to discontinuation or change of therapy. This review discusses the optimal investigation of the child who is a candidate for GH or IGF‐1 therapy so that a diagnosis‐based choice of therapy and dosage can be made. The relevant parameters in the evaluation of growth response are described together with the definitions of poor response. Prevention of poor response is addressed by discussion of strategy for first‐year management with GH and IGF‐1. Adherence to therapy is reviewed as is the recommended action following the identification of the poorly responding patient. The awareness, recognition and management of poor response to growth‐promoting therapy will lead to better patient care, greater cost‐effectiveness and increased opportunities for clinical benefit.  相似文献   
993.
994.
995.
996.
997.
Peripartum myocardial infarction is a rare event that is associated with high mortality rates. The differential diagnosis includes coronary artery dissection, coronary artery thrombosis, vascular spasm, and stenosis. Our evaluation of 2 cases over a 5-year time period has led to a hypothesis that peripartum myocardial infarction is an immune-mediated event secondary to coronary endothelial sensitization by fetal antigen. In our patients, we supplemented standard medical therapy with immunotherapy consisting of corticosteroids, plasmapheresis, and intravenous immunoglobulin. Herein, we present our most recent case-that of a 29-year-old black woman (gravida V, para IV), 2 weeks postpartum with no relevant medical history. She presented with a 1-week history of chest pain. Initial electrocardiographic and cardiac biomarkers were consistent with acute coronary syndrome. Echocardiography revealed reduced systolic function with inferior-wall hypokinesis. Angiography revealed diffuse disease with occlusion of the left anterior descending coronary artery not amenable to revascularization. We were successful in treating the myocardial infarction without the use of catheter-based interventions, by modifying the immunologic abnormalities. Two cases do not make a protocol. Yet we believe that this case and our earlier case lend credence to the hypothesis that peripartum myocardial infarction arises from sensitization by fetal antigens. This concept and the immune-modifying treatment protocol that we propose might also assist in understanding and treating other inflammatory-disease states such as peripartum cardiomyopathy and standard acute myocardial infarction. All of this warrants further investigation.  相似文献   
998.
Recent reviews and meta‐analyses reported structural gray matter changes in patients suffering from adult‐onset posttraumatic stress disorder (PTSD) and in subjects with and without PTSD who experienced childhood trauma. However, it remains unclear if such structural changes are also affecting the white matter. The aim of this systematic review is to provide a comprehensive overview of all empirical investigations measuring white matter integrity in populations affected by PTSD and/or childhood trauma. To this end, results from different methodological approaches were included. Twenty‐five articles are reviewed of which 10 pertained to pediatric PTSD and the effects of childhood trauma measured during childhood, seven to the effects of childhood trauma measured during adulthood, and eight to adult‐onset PTSD. Overall, reductions in white matter volume were reported more often than increases in these populations. However, the heterogeneity of the exact locations indicates only a weak overlap across published studies. In addition, a meta‐analysis was carried out on seven whole‐brain diffusion tensor imaging (DTI) studies in adults. Significant clusters of both increases and decreases were identified in various structures, most notably the cingulum and the superior longitudinal fasciculus. Future research directions are discussed.  相似文献   
999.
Major depression has been repeatedly associated with amygdala hyper‐responsiveness to negative (but not positive) facial expressions at early, automatic stages of emotion processing using subliminally presented stimuli. However, it is not clear whether this “limbic bias” is a correlate of depression or represents a vulnerability marker preceding the onset of the disease. Because childhood maltreatment is a potent risk factor for the development of major depression in later life, we explored whether childhood maltreatment is associated with amygdalar emotion processing bias in maltreated but healthy subjects. Amygdala responsiveness to subliminally presented sad and happy faces was measured by means of fMRI at 3 T in N = 150 healthy subjects carefully screened for psychiatric disorders. Childhood maltreatment was assessed by the 25‐item childhood trauma questionnaire (CTQ). A strong association of CTQ‐scores with amygdala responsiveness to sad, but not happy facial expressions emerged. This result was further qualified by an interaction of emotional valence and CTQ‐scores and was not confounded by trait anxiety, current depression level, age, gender, intelligence, education level, and more recent stressful life‐events. Childhood maltreatment is apparently associated with detectable changes in amygdala function during early stages of emotion processing which resemble findings described in major depression. Limbic hyper‐responsiveness to negative facial cues could be a consequence of the experience of maltreatment during childhood increasing the risk of depression in later life. Limitation: the present association of limbic bias and maltreatment was demonstrated in the absence of psychopathological abnormalities, thereby limiting strong conclusions. Hum Brain Mapp 34:2899–2909, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
1000.
BackgroundUnusual delusional syndromes are rare protean diseases with speculative etiopathogenic mechanisms.MethodsSeven consecutive patients with advanced PD were evaluated over a 15-year period at the Movement Disorders Unit in the Neurology Service, Hospital de Clínicas, Federal University of Paraná, and the Paraná State Parkinson's Patients Association.ResultsWe describe advanced Parkinson's disease patients presenting with unusual delusional syndromes, including cases of Ekbom, Othello, Capgras' and Diogenes syndromes, reduplicative paramnesia and mirrored-self misidentification.ConclusionThere are a few isolated reports of unusual neuropsychiatric disorders in patients with PD. We believe that these syndromes associated with advanced PD in elderly patients presenting with cognitive impairment and polypharmacy are probably often underestimated. Neurologists should be aware for these rare and treatable conditions.  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