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   825篇
  免费   43篇
  国内免费   4篇
耳鼻咽喉   6篇
儿科学   34篇
妇产科学   23篇
基础医学   109篇
口腔科学   53篇
临床医学   71篇
内科学   149篇
皮肤病学   18篇
神经病学   71篇
特种医学   30篇
外科学   90篇
综合类   21篇
预防医学   53篇
眼科学   14篇
药学   68篇
中国医学   9篇
肿瘤学   53篇
  2024年   3篇
  2023年   6篇
  2022年   29篇
  2021年   43篇
  2020年   33篇
  2019年   30篇
  2018年   34篇
  2017年   36篇
  2016年   32篇
  2015年   29篇
  2014年   37篇
  2013年   65篇
  2012年   70篇
  2011年   66篇
  2010年   45篇
  2009年   40篇
  2008年   46篇
  2007年   46篇
  2006年   44篇
  2005年   36篇
  2004年   23篇
  2003年   17篇
  2002年   7篇
  2001年   6篇
  2000年   6篇
  1999年   5篇
  1998年   1篇
  1997年   1篇
  1996年   4篇
  1995年   3篇
  1993年   2篇
  1992年   1篇
  1991年   1篇
  1990年   5篇
  1989年   6篇
  1988年   3篇
  1986年   4篇
  1985年   2篇
  1982年   1篇
  1977年   1篇
  1975年   1篇
  1966年   1篇
  1965年   1篇
排序方式: 共有872条查询结果,搜索用时 31 毫秒
21.
BACKGROUND: Little is known about what specific cognitive functions are affected by elevated blood pressure (BP) and how orthostatic BP change is related to cognitive impairment. The aim of this study was to determine the effect of BP and its postural change on cognitive functions in otherwise healthy elders. METHODS: In 70 healthy persons (mean age, 72 +/- 4 years), supine systolic BP (SBP) was assessed 3 times using a sphygmomanometer, and the average values were obtained for the analysis. After 1, 3, and 5 minutes of standing, 3 BP measurements were obtained and the orthostatic SBP changes were determined by subtracting these values from the supine average. Neuropsychological tests were administered to assess short-term and long-term verbal and visual memory, visuospatial skills, and frontal-executive functions. Participants were considered impaired in the specific cognitive performance if their scores fell below the 25th percentile of the study population. Multiple logistic regression models were used to evaluate the relation of SBP and the magnitude of orthostatic SBP decline to risk for impairment in each of the cognitive tests. RESULTS: Controlling for potential confounders, each 10 mmHg increase in supine SBP was associated with a 2.31-fold increase (95% confidence interval, 1.14 to 4.66) in risk for impairment in psychomotor speed and set shifting as measured using the Trailmaking Part-B test. There was no significant association between cognitive functions and orthostatic SBP decline at 1, 3, and 5 minutes of standing. CONCLUSION: Elevation of BP is associated with a selective impairment in executive function in otherwise healthy community-dwelling elders.  相似文献   
22.
23.
24.
25.

Introduction

This study seeks to compare two treatment methods of lateral epicondylitis: corticosteroid injection (CSI) and a local anesthetic injection (LAI).

Materials and methods

In this single-blinded randomized clinical trial, 138 patients with the diagnosis of lateral epicondylitis were assigned either into CSI group receiving methylprednisolone 1 ml (49 patients) or LAI group (51 patients) receiving procaine 1 ml 2 % in a single dose at the maximal point tenderness site. The primary outcome measure was elbow disability using Quick DASH, and secondary outcome measures were pain intensity using Visual Analogue Scale (VAS) and recurrence rate at pretreatment visit and at 3-, 6- and 12-week post-treatment visits.

Results

There were no significant differences between the patients in both groups for demographic factors including age, gender, dominant hand, involved hand, and work pressure. Before treatment, the patients in both groups were suffering from the same rates of elbow disability and pain as measured by Quick DASH and VAS, respectively, (p > 0.05). In general, the recovery rate (comparison between pretreatment visit and last post-treatment visit) was significantly more effective and higher in CSI than LAI. CSI was dramatically more effective at 3-week visit, but less and less effective at 6- and 12-week visits. At 12-week visit the recurrence rate was 34.7 % (17 patients) in CSI group.

Conclusion

For lateral epicondylitis, CSI has the best short-term treatment results yet the highest recurrent rates. The combination of CSI with other treatment option or with a change in injection technique from single injection to peppering injection may be promising.  相似文献   
26.
The purpose of this study was to compare facial growth in patients with unilateral complete cleft lip and palate (UCLP) in whom the palate was repaired with the von Langenbeck procedure at 8 months (L-8), or the Wardill procedure at 18 months (W-18). A total of 151 unaffected subjects were used as a reference series. Sixty-one adult patients, 34 in the L-8 group and 27 in the W-18 group, were investigated clinically and with lateral skull radiography and also filled out a questionnaire about their dental condition. Multiple linear regression was used to analyse the effects of the surgical strategy, sex, and the presence of a velopharyngeal flap on several dependent variables indicating sagittal jaw relations, vertical jaw relations, and inclination of incisors. The UCLP group was characterised by a short (n-sp) and retrusive maxilla (s-n-ss) and a retrusive mandible for women (s-n-sm), larger maxillary inclination (NSL/NL), more retroclined lower incisors (ILI/ML), shorter upper facial heights (n-sp) and normal total face height (n-gn) than the reference group. In the UCLP group there were significant differences between men and women in mandibular prognathism (s-n-sm), maxillary/mandibular relations (ss-n-sm), maxillary inclination (NSL/NL), total anterior facial height (n-gn), and upper anterior facial height (n-sp). Lateral crossbite was found in 20% of the UCLP group. The prevalence was similar in the L-8 and W-18 groups. Almost 80% of the patients in the UCLP group considered that their dental condition was good. The choice of surgical strategy had no significant influence on the variables measured on facial morphology.  相似文献   
27.

Background

The aim of this investigation was to assess the effects of different treatments of demineralised enamel on microleakage under orthodontic brackets.

Methods

Seventy-five intact premolars were randomly assigned to five groups. The teeth in groups 2 through 5 were immersed in a demineralising solution for 16 weeks. In groups 1 (control) and 2 (demineralised/control), conventional acid etching was used. In group 3, sodium hypochlorite (NaOCl) was applied on the enamel surface for 1 min after acid etching, and in group 4, Transbond Plus (3M Unitek, Monrovia, CA, USA) self-etching primer (SEP) was used. The teeth in group 5 were treated with 2% sodium fluoride (NaF) for 4 min before etching. After bracket bonding, the specimens were thermocycled, sealed with nail varnish, immersed in 0.5% basic fuchsine solution for 24 h and sectioned. Microleakage was measured under a stereomicroscope for the enamel-adhesive and adhesive-bracket interfaces of both occlusal and gingival sides.

Results

Demineralised teeth showed more microleakage at the enamel-adhesive interface on both occlusal and gingival sides compared to sound teeth, but the difference was not significant (P > 0.005). Treating the demineralised enamel with 5% NaOCl or Transbond Plus SEP was not effective in reducing microleakage. NaF treatment followed by acid etching of demineralised enamel resulted in significantly lower microleakage in most comparisons (P < 0.005).

Conclusions

The use of 2% NaF on hypomineralised enamel before the bracket bonding procedure is an effective way to decrease microleakage.  相似文献   
28.
29.
30.
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