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   14510篇
  免费   844篇
  国内免费   90篇
耳鼻咽喉   111篇
儿科学   753篇
妇产科学   289篇
基础医学   1960篇
口腔科学   224篇
临床医学   1218篇
内科学   3124篇
皮肤病学   337篇
神经病学   1382篇
特种医学   823篇
外国民族医学   4篇
外科学   2136篇
综合类   192篇
一般理论   3篇
预防医学   880篇
眼科学   177篇
药学   740篇
  2篇
中国医学   12篇
肿瘤学   1077篇
  2022年   77篇
  2021年   193篇
  2020年   114篇
  2019年   167篇
  2018年   225篇
  2017年   174篇
  2016年   176篇
  2015年   228篇
  2014年   296篇
  2013年   378篇
  2012年   592篇
  2011年   644篇
  2010年   441篇
  2009年   413篇
  2008年   562篇
  2007年   605篇
  2006年   589篇
  2005年   672篇
  2004年   513篇
  2003年   487篇
  2002年   516篇
  2001年   459篇
  2000年   498篇
  1999年   396篇
  1998年   293篇
  1997年   295篇
  1996年   272篇
  1995年   221篇
  1994年   233篇
  1993年   201篇
  1992年   313篇
  1991年   294篇
  1990年   286篇
  1989年   332篇
  1988年   291篇
  1987年   286篇
  1986年   260篇
  1985年   268篇
  1984年   213篇
  1983年   170篇
  1982年   125篇
  1981年   129篇
  1980年   89篇
  1979年   155篇
  1978年   114篇
  1977年   82篇
  1976年   102篇
  1975年   86篇
  1974年   105篇
  1973年   95篇
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
101.
102.
Dumas  JM; Edde  DJ 《Radiology》1986,160(2):453-456
In a prospective study conducted over a 12-month period, 30 patients underwent double-contrast arthrography of the knee followed by arthroscopic study. An 80% correlation rate was found between results. Arthrography had a higher rate of accuracy (93%) than arthroscopy (84%) and had a 7% false-positive and 0% false-negative rate. A commonly overlooked arthrographic sign--the triple-S or stuck sail sign--was 91% accurate in the prediction of meniscal tears. The complementary nature of the two examinations is discussed.  相似文献   
103.
Cervical root stimulation (CRS) was compared with conventional EMG, nerve conduction, and late response studies in 34 patients with possible cervical radiculopathy. Cervical roots were stimulated by monopolar needles inserted into paraspinal muscles, recording compound muscle action potentials in biceps, triceps, and abductor digiti minimi muscles. In 18 patients with clinical evidence of radiculopathy, EMG was abnormal in 11 (61%), but CRS was abnormal in all 18. Of 16 patients with symptoms but no signs of radiculopathy, EMG was abnormal in 5 (31%) and CRS was abnormal in 9 (56%).  相似文献   
104.
In spite of extensive investigations of the rat's meso-cortico-limbic system, the dopaminergic (DA) innervation of the hippocampal formation (HF) has not heretofore been visualized by histochemical techniques. However pharmacological and biochemical studies strongly suggested its existence. We used tyrosine-hydroxylase (TH) as an immunocytochemical marker of DA neurons in rats in which the noradrenaline cortical innervation was previously destroyed by neurotoxins. The absence of noradrenergic axons was routinely controlled with dopamine-beta-hydroxylase immunocytochemistry. TH-positive axons, thus DA axons, reach the HF primarily through the fimbria in which they occupy a specific lateral sector. They innervate the ventral and caudal parts of the HF, the subiculum and the adjacent CA1 hippocampal field being the main targets. This DA terminal field in the HF, matches with the area projecting toward the nucleus accumbens. Thus the hippocampo-striatal projections which represent a link of functional importance between the limbic and central motor systems might be modulated by the dopaminergic meso-cortico-limbic pathway. The present immunocytochemical study confirms the very dense innervation of the entorhinal cortex (EC): DA axons are organized in dense fiber islands and occupy primarily the superficial layers (I-II-III). Da innervation predominates in the lateral part of EC, which is the site of multimodal cortical afferences and therefore relays information between the whole neocortex and the hippocampus. Thus the DA system could play an important role of modulation on hippocampal and parahippocampal functions.  相似文献   
105.
106.
Management of abdominal sepsis   总被引:2,自引:0,他引:2  
Introduction: Today the management of the different forms of peritonitis is generally standardised. The classification of primary and secondary peritonitis is well accepted. From a pathophysiological point of view, postoperative and post-traumatic peritonitis should be considered as independent entities. The bacteriological isolates from the inflamed peritoneal cavity do not correlate with the clinical course, and the occurrence of enterococci and bacteroides may be slightly related to ongoing infectious complications. Classification: Valuable scoring systems mainly rely on systemic signs of the septic disease and seem to better differentiate the prognosis of the disease than more surgically oriented scores do. Although the scoring systems did not allow any clinical decision, they should be used to help better compare patients treated in different institutions. The observation of the minor relevance of bacteriology and the superiority of general sepsis scores agrees with the fact that pre-existing septic organ dysfunction and pre-existing comorbidity are the main determinants of mortality. Treatment: Surgical therapy focuses on the control of the source of infection because it has been clearly shown that, without resolving the source of infection, the prognosis remains poor. Adjuvant surgical measures aim at the further reduction of the bacterial load in the peritoneal cavity. Planned relaparotomy, relaparotomy on demand, and continuous closed peritoneal lavage are used. Results: Clinical results proved these methods to be equally effective although pathophysiological considerations favour closed peritoneal lavage. Conclusion: Summarising the available data, we need a more sophisticated understanding of the pathophysiology of the peritonitis, and well-designed clinical studies are necessary to define the optimal surgical treatment modalities. Received: 27 November 1997  相似文献   
107.
108.
Sacral insufficiency fractures develop over a period of time and show time-dependent changes. We report on 15 CT examinations of 5 patients with early-stage insufficiency fractures of the sacrum. In 4 patients only irregular sclerosis without distinct fracture lines was present in 7 of 8 fractures. Of these 4 patients; 3 exhibited intraosseous gas inclusions in a ventral part of a lateral mass; 5 of 8 fractures disclosed a ventral cortical break. When distinct fracture lines had developed in 1 patient, intraosseous vacuum phenomenon had disappeared. Fracture lines evolve over weeks to months and show central bone absorption. The fractures can heal as demonstrated in 4 of 6 fractures in 3 patients, can persist over 1 year without significant changes or can progress to pseudoarthrosis with bone destruction similar to neuropathic joint disease. Intraosseous vacuum phenomena can persist to this stage. Intraosseous vacuum phenomenon is recognized as a potential finding in the early stage of sacral insufficiency fracture, which also is true for irregular sclerosis and ventral cortical disruption. Correspondence to: A. Stäbler  相似文献   
109.
110.
Patellofemoral joint: kinematic MR imaging to assess tracking abnormalities   总被引:4,自引:0,他引:4  
Shellock  FG; Mink  JH; Fox  JM 《Radiology》1988,168(2):551-553
The patellofemoral joint was imaged with magnetic resonance (MR) in the axial plane while the knee was positioned from 0 degrees to 32 degrees of flexion (nine positions). These multiple sequential images obtained within the early phases of flexion of the knee were viewed in a "cine-loop" format, producing a kinematic study that clearly demonstrated the relationship of the patella to the trochlear groove. Four healthy subjects and one patient with known bilateral subluxing patellae were studied. The preliminary results suggest that kinematic MR imaging of the patellofemoral joint is potentially useful for the evaluation of patellar tracking abnormalities.  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