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   4714篇
  免费   332篇
  国内免费   9篇
耳鼻咽喉   168篇
儿科学   89篇
妇产科学   76篇
基础医学   668篇
口腔科学   246篇
临床医学   434篇
内科学   872篇
皮肤病学   52篇
神经病学   468篇
特种医学   219篇
外科学   617篇
综合类   35篇
一般理论   3篇
预防医学   411篇
眼科学   109篇
药学   252篇
中国医学   8篇
肿瘤学   328篇
  2023年   43篇
  2021年   55篇
  2020年   76篇
  2019年   109篇
  2018年   102篇
  2017年   90篇
  2016年   77篇
  2015年   79篇
  2014年   96篇
  2013年   158篇
  2012年   217篇
  2011年   211篇
  2010年   129篇
  2009年   119篇
  2008年   215篇
  2007年   193篇
  2006年   184篇
  2005年   195篇
  2004年   183篇
  2003年   146篇
  2002年   141篇
  2001年   179篇
  2000年   148篇
  1999年   115篇
  1998年   61篇
  1997年   42篇
  1996年   61篇
  1995年   50篇
  1994年   44篇
  1993年   40篇
  1992年   90篇
  1991年   100篇
  1990年   117篇
  1989年   105篇
  1988年   69篇
  1987年   90篇
  1986年   79篇
  1985年   69篇
  1984年   68篇
  1983年   46篇
  1982年   44篇
  1981年   30篇
  1980年   36篇
  1979年   62篇
  1978年   37篇
  1975年   35篇
  1974年   37篇
  1973年   31篇
  1970年   35篇
  1969年   29篇
排序方式: 共有5055条查询结果,搜索用时 15 毫秒
1.
2.
3.
Fronto-ethmoidal mucocoeles: a histopathological analysis.   总被引:1,自引:0,他引:1  
From a series of 118 fronto-ethmoidal mucocoeles, 40 specimens have been submitted to detailed histological analysis. The frequency of each epithelial and sub-epithelial component is considered and reveals features which support a dynamic theory of bone resorption and formation rather than that of pressure erosion in the pathogenesis of mucocoeles.  相似文献   
4.
20 eyes of 11 patients suffering from most severe eye burns of grade 4 or worse were treated in addition to various other drugs with epiderm growth factor (EGF) or placebo in a double-blind test. Among 10 eyes treated with EGF, 6 achieved complete regeneration of the corneal epithelium, and 1 additional case, of the conjunctival epithelium. Among the eyes receiving placebo, only 3 out of 10 healed; all of them were also treated with fibronectin. Although in these very difficult cases EGF could not be investigated as a single therapy, and various other undefined factors may have been effective, in the extended course of the disease the period of EGF treatment was marked by a significant better regeneration of the epithelium.  相似文献   
5.
Usher syndrome: clinical findings and gene localization studies   总被引:3,自引:0,他引:3  
The issue of genetic heterogeneity is a critical problem in the localization of the gene(s) for Usher syndrome. Based on the data obtained on families studied to date, the differences between type I and type II Usher syndrome appear quite distinct with regard to auditory and vestibular function. Although the majority of families can be confidently diagnosed as typical type I or type II, clinical investigations revealed four families with findings that did not fit into either of the two more common subtypes. These findings emphasize the critical importance of an in-depth clinical analysis concomitant with the linkage investigation to assure accurate subtyping of Usher syndrome. Based on an analysis of only those families with definite type I or type II Usher syndrome, approximately 17% of the genome can be excluded as a potential site of the gene for type I, and 14% can be excluded as the site for the type II gene. This study will continue until the Usher gene(s) is successfully localized.  相似文献   
6.
7.
MR imaging was reviewed in 66 pediatric spinal cord patients with diagnoses of posterior fossa tumor (n = 8), primary spinal cord tumor (n = 3), metastatic disease (n = 11), neuroectodermal disorder (n = 8), congenital malformation (n = 14), trauma (n = 2), and demyelinating, neurodegenerative, or metabolic disorders (n = 9). MR proved to be useful in delineating the extent of posterior fossa and cord tumor including metastasis to the cord. MR was of limited value in demyelinating and metabolic disorders. Arnold Chiari malformations, syringomyelia, tethered cord and meningoceles were all easily evaluated using MR.  相似文献   
8.
Benign intracranial hypertension (BIH) is reported in three children from Australia and one from New Zealand, who were being treated with recombinant human growth hormone (rhGH). Three males and one female, aged between 10.5 and 14.2 y, developed intracranial hypertension within 2 weeks to 3 months of starting treatment. A national database, OZGROW, has been prospectively collecting data on all 3332 children treated with rhGH in Australia and New Zealand from January 1986 to 1996. The incidence of BIH in children treated with growth hormone (GH) is small, 1.2 per 1000 cases overall, but appears to be greater with biochemical GHD (<10IUml -1), i.e. 6.5/1000 (3 in 465 cases), relative risk 18.4, 95% confidence interval 1.9-176.1, than in all other children on the database. The incidence in patients with Turner's syndrome was 2.3/1000 (1 in 428 cases). No cases in patients with partial GHD (10–20 IUml -1) or chronic renal failure were identified. Possible causative mechanisms are discussed. The authors'practice is now to start GH replacement at less than the usual recommended dose of 14IUm-2 week-1 in those children considered to be at high risk of developing BIH. Ophthalmological evaluation is recommended for children before and during the first few months following commencement of rhGH therapy and is mandatory in the event of peripheral or facial oedema, persistent headaches, vomiting or visual symptoms. The absence of papilledema does not exclude the diagnosis.  相似文献   
9.
10.
The relationship between dietary fat intake and fasting plasma lipid levels was assessed in 35 female and 19 male adolescents recruited from two local education authority schools in Norwich, UK. Dietary intakes were assessed using a 7-day weighed dietary record method, coupled with the collection of duplicate diets. Fat and energy intakes calculated using food composition tables were compared with values obtained by direct analysis of duplicate diets. Fasting plasma lipid levels (total, HDL and LDL cholesterol and triglycerides) were measured and compared with total dietary lipids and fatty acid intakes. The average proportion of energy consumed as fat was higher than is currently considered desirable but lower than previous studies have reported for adults. Mean serum total cholesterol values were 4.2 (SEM 0.1) mmol for females and 4.5 (SEM 0.2) mmol for males; this difference was not statistically significant. In male subjects the dietary fatty acid profiles were significantly correlated with several parameters of plasma lipid status which are thought to be risk factors for coronary heart disease, and in particular with the ratio of total:HDL cholesterol.  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