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   7160篇
  免费   373篇
  国内免费   10篇
耳鼻咽喉   134篇
儿科学   444篇
妇产科学   174篇
基础医学   776篇
口腔科学   107篇
临床医学   424篇
内科学   1359篇
皮肤病学   193篇
神经病学   496篇
特种医学   204篇
外科学   982篇
综合类   289篇
预防医学   444篇
眼科学   338篇
药学   538篇
中国医学   37篇
肿瘤学   604篇
  2023年   41篇
  2022年   96篇
  2021年   187篇
  2020年   111篇
  2019年   158篇
  2018年   196篇
  2017年   135篇
  2016年   187篇
  2015年   165篇
  2014年   280篇
  2013年   340篇
  2012年   488篇
  2011年   533篇
  2010年   296篇
  2009年   267篇
  2008年   396篇
  2007年   392篇
  2006年   396篇
  2005年   324篇
  2004年   322篇
  2003年   282篇
  2002年   211篇
  2001年   141篇
  2000年   160篇
  1999年   138篇
  1998年   52篇
  1997年   51篇
  1996年   55篇
  1995年   37篇
  1994年   28篇
  1993年   33篇
  1992年   62篇
  1991年   53篇
  1990年   48篇
  1989年   58篇
  1988年   44篇
  1987年   61篇
  1986年   49篇
  1985年   56篇
  1984年   52篇
  1983年   34篇
  1978年   29篇
  1977年   31篇
  1974年   34篇
  1973年   49篇
  1972年   42篇
  1971年   37篇
  1970年   30篇
  1969年   35篇
  1968年   36篇
排序方式: 共有7543条查询结果,搜索用时 15 毫秒
1.
2.
Studies on the development of imaging agents for targeting neuroreceptors is an area of considerable interest owing to the limited availability of specific as well as selective radiolabeled agents. Therefore, with an aim of developing a receptor-specific agent, iminodiacetic acid (IDA) derivative of 5-hydroxy tryptamine viz., HTIDA has been synthesized. HTIDA could be radiolabeled with the synthon [(99m)Tc(CO)(3)(H(2)O)(3)](+) in >98% yield. The biodistribution studies in normal Swiss mice showed that the (99m)Tc(CO)(3)-HTIDA crosses the blood-brain barrier successfully with a brain uptake of 0.5%ID/g at 5min post injection. The other relevant observations from biodistribution studies included no significant uptake in any other organ and fast clearance from blood, lungs and liver.  相似文献   
3.
Three cases of enteritis necroticans seen at Port Moresby General Hospital are described. All three cases proved diagnostic problems and in all three the diagnosis was made only at laparotomy. While the condition is uncommon in Port Moresby, these cases indicate that it must now be considered earlier rather than later.  相似文献   
4.
5.
Reported herein is a case of obsessive–compulsive disorder with persistent and distressing musical obsessions along with other symptoms. Advanced source analysis of electroencephalographic data indicated high spectral power over the bifrontal region. The musical symptoms were resistant to pharmacotherapy but there was some reduction in frequency and duration of musical obsessions with thought-stopping technique.  相似文献   
6.
Infections caused by extended-spectrum beta-lactamase (ESBL)-producing pathogens, particularly Klebsiella pneumoniae, are increasing. The epidemiology of ESBL-producing K. pneumoniae, the mechanisms of resistance, and treatment strategies for infections caused by these organisms are reviewed.  相似文献   
7.
Object Intracranial aneurysms are rare in children and have different epidemiological, clinical, and morphological characteristics and outcome from those in adults. Materials and methods We analyzed demographic, clinical, radiologic features, treatment, and outcome in 55 patients <18 years of age, treated from Jan 1995 through December 2005. Results Intracranial aneurysms in children below 18 years constituted 4% of all intracranial aneurysms. Internal Carotid artery (ICA) bifurcation was the commonest location. About half of the aneurysms were complex. Three-fourth of the patients required surgical treatment. Two patients died, constituting 5% mortality. Two patients (5%) had poor outcome, whereas the majority (90%) had a favorable outcome. Conclusions Pediatric aneurysms have male predominance, higher incidence of clinical features of mass effect or seizures, high incidence of large, traumatic/mycotic aneurysms, associated illnesses and ICH/IVH and hydrocephalus, better Hunt and Hess grades at presentation, ICA bifurcation as the commonest site, and better outcome than their adult counterparts.  相似文献   
8.
One hundred insulin-dependent diabetic patients (age < 45 years, 53 smokers) were followed for six years. The age, duration of diabetes and mean glycated haemoglobin levels, were comparable between the smokers and non-smokers. Microvascular complications (retinopathy and increased urine albumin excretion) were commoner and more severe in the smoking group at six years, particularly in heavy smokers. Of the 45 original smokers reviewed at six years, 12 (27%) had stopped, six of whom had developed microvascular complications. Only two of the ''heavy'' initial smokers, likely to be at most risk, had stopped smoking, and three original non-smokers had started smoking.  相似文献   
9.
10.
Between 1986–1990, 290 patients with squamouscell carcinoma of the hypopharynx were assessed at the S. S. K. M. Hospital Calcutta, out of the total of 1460 number of Head Neck cancer, (19.8%). The most frequent initial symptom was a foreign body sensation in the throat (70%), and males were affected more than females (9.8 : 1.2). The peak age incidence was found between 40 and 50 years (24%). Most of the patients came in advanced stages with cervical lymph node metastases (60%). One interesting fact that came out from the present study is the Right pyriform fassa was more commonly affected than the left in righthanded persons (56.9%). Though the reason is not clear it could be due to right — sided swallow, as one side may be predominant in funtion.  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