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   11061篇
  免费   364篇
  国内免费   34篇
耳鼻咽喉   150篇
儿科学   192篇
妇产科学   285篇
基础医学   2121篇
口腔科学   236篇
临床医学   575篇
内科学   1083篇
皮肤病学   430篇
神经病学   833篇
特种医学   1647篇
外科学   1477篇
综合类   80篇
预防医学   768篇
眼科学   85篇
药学   1099篇
中国医学   92篇
肿瘤学   306篇
  2023年   36篇
  2022年   21篇
  2021年   62篇
  2020年   46篇
  2019年   60篇
  2018年   192篇
  2017年   129篇
  2016年   184篇
  2015年   124篇
  2014年   222篇
  2013年   382篇
  2012年   704篇
  2011年   1038篇
  2010年   481篇
  2009年   176篇
  2008年   760篇
  2007年   927篇
  2006年   908篇
  2005年   730篇
  2004年   650篇
  2003年   657篇
  2002年   562篇
  2001年   376篇
  2000年   486篇
  1999年   280篇
  1998年   109篇
  1997年   73篇
  1996年   54篇
  1995年   56篇
  1994年   46篇
  1993年   41篇
  1992年   26篇
  1991年   27篇
  1990年   33篇
  1989年   35篇
  1988年   44篇
  1987年   25篇
  1986年   31篇
  1985年   40篇
  1984年   28篇
  1983年   27篇
  1982年   38篇
  1981年   41篇
  1980年   42篇
  1979年   28篇
  1978年   33篇
  1976年   29篇
  1975年   28篇
  1974年   23篇
  1973年   24篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
OBJECTIVE: Nocturnal enuresis is a common pediatric problem, the etiology of which is unclear. In recent years, various studies have been published stating that children with nocturnal enuresis exhibit growth and skeletal maturation retardation. METHODS: In this cross-sectional study, we included 27 patients (16 boys, 11 girls) between the ages of 6 and 14 years who had presented with primary nocturnal enuresis (PNE) complaints. We included in the evaluation 19 healthy subjects (12 boys, 7 girls), who were the siblings of the children with PNE, as the control group. RESULTS: The patients in both groups were similar in chronological age, bone age, height and weight, with no significant difference between groups (P>0.05). CONCLUSION: The two groups in our study consisted of the same genetic background. Thus, our results were found to be different from the previous studies. We have concluded that there is no direct relationship between enuresis nocturnal and skeletal maturation.  相似文献   
4.
5.
Computerized information systems, especially decision support systems, have become an increasingly important role in medical applications, particularly in those where important decision must be made effectively and reliably. But the possibility of using computers in medical decision making is limited by many difficulties, including the complexity of conventional computer languages, methodologies and tools. Thus a conceptual simple decision making model with the possibility of automating learning should be used. In this paper we introduce a cardiological knowledge-based system based on the decision tree approach supporting the mitral valve prolapse determination. Prolapse is defined as the displacement of a bodily part from its normal position. The term mitral valve prolaps (PMV), therefore, implies that the mitral leaflets are displaced relative to some structure, generally taken to be the mitral annulus. The implications of the PMV are the following: disturbed normal laminar blood flow, turbulence of the blood flow, injury of the chordae tendinae, the possibility of thrombus's composition, bacterial endocarditis, and finally hemodynamic changes defined as mitral insufficiency and mitral regurgitation. Uncertainty persists about how it should be diagnosed and about its clinical importance. It is our deep belief that the echocardiography enables properly trained experts armed with proper criteria to evaluate PMV almost 100%. But unfortunately, there are some problems concerned with the use of echocardiography. In that manner we have decided to start a research project aimed at finding new criteria and enabling the general practitioner to evaluate PMV using conventional methods and to select potential patients from the general population. To empower one to perform needed activities we have developed a computer tool called ROSE (computeRised prOlaps Syndrom dEtermination) based on algorithms of automatic learning. This tool supports the definition of new criteria and the selection of potential PMV-patients.  相似文献   
6.
7.
8.
9.
10.
High serum fluoride (F-) in patients with chronic renal failure (CRF) and end-stage renal disease (ESRD) is associated with risk of renal osteodystrophy and other bone changes. This study was done to determine F- in normal healthy controls and patients with ESRD on haemodialysis (HD) or peritoneal dialysis (PD). Seventeen healthy controls (12 males, 5 females) and 39 ESRD patients on dialysis (17 males, 22 females) were recruited in the study in a community with 47.4 +/- 3.28 microM/l (range 44-51 microM/l) of F- content in drinking water. Control subjects showed a mean serum F- concentration of 1.08 +/- 0.350 microM/l. Males in control group showed slightly higher F- levels (1.15 +/- 0.334, range 0.55-1.9 microM/l) than females (0.92 +/- 0.370, range 0.6-1.5 microM/l). Mean serum F- concentration did not correlate significantly with age and sex among control subjects, whereas such correlation was observed in patients with ESRD on dialysis. Mean serum F- concentration was significantly higher in patients on dialysis (2.67 +/- 1.09, range 0.8-5.2 microM/l) than normal controls. When grouped according to sex, the mean serum F- concentration in males (3.05 +/- 1.04, range 1.8-5.2 microM/l) was significantly higher than females (2.38 +/- 1.08, range 0.8-5.2 microM/l). When patients were grouped according to age, it was observed that F- concentration was significantly higher in patients with age groups 21-70 (2.86 +/- 1.05) than those with age group 13-20 years (1.42 +/- 0.531). Thus F- concentration correlated with age and sex, being higher in males and above 20 years. Despite appreciable clearance of F- (39-90%) across the peritoneum, patients on CAPD showed higher serum F- concentration than those on HD (3.1 +/- 1.97 vs 2.5 +/- 1.137 microM/l). Of the total 39 patients on dialysis 39% had their serum F- concentration above 3.0 microM/l, posing the risk of renal osteodystrophy.   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